LP3972SQX-E514 [TI]

1-CHANNEL POWER SUPPLY SUPPORT CKT, QCC40, 5 X 5 MM, LLP-40;
LP3972SQX-E514
型号: LP3972SQX-E514
厂家: TEXAS INSTRUMENTS    TEXAS INSTRUMENTS
描述:

1-CHANNEL POWER SUPPLY SUPPORT CKT, QCC40, 5 X 5 MM, LLP-40

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LP3972  
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SNVS468K SEPTEMBER 2006REVISED MAY 2013  
Power Management Unit for Advanced Application Processors  
Check for Samples: LP3972  
1
FEATURES  
APPLICATIONS  
2
Compatible With Advanced Applications  
Processors Requiring DVM (Dynamic Voltage  
Management)  
PDA Phones  
Smart Phones  
Personal Media Players  
Digital Cameras  
Three Buck Regulators for Powering High-  
Current Processor Functions or I/Os  
Application Processors  
Six LDOs for Powering RTC, Peripherals, and  
I/Os  
Marvell PXA  
Freescale  
Samsung  
Backup Battery Charger With Automatic  
Switch for Lithium-Manganese Coin Cell  
Batteries and Super Capacitors  
I2C Compatible High-Speed Serial Interface  
DESCRIPTION  
The LP3972 is a multi-function programmable Power  
Management Unit designed especially for advanced  
application processors. The LP3972 is optimized for  
low-power handheld applications and provides six  
low-dropout low-noise linear regulators, three DC/DC  
magnetic buck regulators, a back-up battery charger,  
and two GPIOs. A high-speed serial interface is  
included to program individual regulator output  
voltages as well as on and off control.  
Software Control of Regulator Functions and  
Settings  
Precision Internal Reference  
Thermal Overload Protection  
Current Overload Protection  
Tiny 40-Pin 5x5 mm WQFN Package  
KEY SPECIFICATIONS  
Buck Regulators  
Programmable VOUT from 0.725 to 3.3V  
Up to 95% efficiency  
Up to 1.6A output current  
±3% output voltage accuracy  
LDOs  
Programmable VOUT of 1.0V–3.3V  
±3% output voltage accuracy  
150/300/400 mA output currents  
LDO_RTC 30 mA  
LDO1 300 mA  
LDO2 150 mA  
LDO3 150 mA  
LDO4 150 mA  
LDO5 400 mA  
100 mV (typ) dropout  
1
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of  
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.  
2
All trademarks are the property of their respective owners.  
PRODUCTION DATA information is current as of publication date.  
Products conform to specifications per the terms of the Texas  
Instruments standard warranty. Production processing does not  
necessarily include testing of all parameters.  
Copyright © 2006–2013, Texas Instruments Incorporated  
LP3972  
SNVS468K SEPTEMBER 2006REVISED MAY 2013  
www.ti.com  
Application Circuits  
V
IN  
Back-up  
Battery  
+
-
LDO1  
BUCK1  
BUCK2  
BUCK3  
LDO2  
LDO3  
LP3972  
LDO4  
LDO5  
RTC  
Figure 1. Simplified Application Circuit  
2
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SNVS468K SEPTEMBER 2006REVISED MAY 2013  
Li-ion/polymer cell  
+
See notes  
Cvdd  
4.7 mF  
LP3972 PMIC  
SYNC  
35  
VIN VDDA  
APPLICATION  
PROCESSOR  
DC SOURCE  
4.5 œ 5.5V  
27  
20  
6
40  
26 14  
31  
Cchg_det  
4.7 mF  
Clock  
divider  
37  
PWR_EN  
Lsw1 2.2 mH  
COMP  
39  
CPU  
SW1  
CORE  
BUCK1  
BUCK2  
EOC  
10 mF  
VBUCK2  
10 mF  
VFB1  
5
VinBUBATT  
15  
Lsw2 2.2 mH  
19  
VoutLDO_RTC  
Vout  
Switch  
SW2  
VFB2  
USB  
23  
32  
Lsw3 2.2 mH  
PWR_ON  
1
UART  
SW3  
BUCK3  
VFB3  
10 mF  
28  
OSC  
SYS_EN  
36  
VoutLDO1  
BG  
MVT  
VIN  
GPIO1/nCHG_EN  
29  
LDO1  
Wake up  
7
Cldo2  
0.47 mF  
2
30  
3
nTEST_JIG  
GPIO2  
AP_IO  
Power  
ON-OFF  
Logic  
VoutLDO3  
LDO3  
LDO4  
12  
Cldo3  
0.47 mF  
SPARE  
nRSTI  
VoutLDO4  
VinLDO4  
VinLDO5  
PLL  
9
13  
Cldo4  
0.47 mF  
RESET  
PWR_EN  
Logic Control  
and registers  
Internal HW reset for  
test purposes  
VoutLDO5  
SRAM  
RTC  
LDO5  
25  
Cldo5  
0.47 mF  
SYS_EN  
VIN  
VoutLDO_RTC  
16  
LDORTC  
CldoRTC  
VoutLDO2  
8
1.0 mF  
See notes  
LDO2  
CODEC  
Cldo1  
1.0 mF  
Power On  
Reset  
3.3V  
Vout Switch  
VDDA  
10k  
I2C_SCL  
22  
21  
I2C  
Thermal  
Shutdown  
10k  
I2C_SDA  
BIAS  
vref  
24  
nRSTO  
4
EXT_WAKEUP  
nBATT_FLT  
17  
11  
18  
33  
34  
38  
10  
VREF  
Cvrefh  
10 nF  
PGND1 PGND2 PGND3  
BGND1,2,3 GND1  
The I2C lines are pulled up via a I/O source  
VINLDOs 4, 5 can either be powered from main battery source, or by a buck regulator or VIN  
.
Figure 2. Application Circuit  
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Connection Diagram  
30 29 28 27 26 25 24 23 22 21  
21 22 23 24 25 26 27 28 29 30  
31  
32  
20  
19  
18  
20  
19  
18  
31  
32  
33  
34  
33  
34  
17  
16  
15  
14  
17  
16  
15  
14  
35  
36  
37  
35  
36  
37  
13  
12  
11  
13  
12  
11  
38  
39  
40  
38  
39  
40  
1
2
3
4
5
6
7
8
9
10  
10  
9
8
7
6
5
4
3
2
1
Top View  
Bottom View  
Note: Circle marks pin 1 position.  
40-Pin WQFN, Package Number RSB0040A  
PIN DESCRIPTIONS  
Pin No.  
Name  
I/O  
Type(1)  
Description  
1
PWR_ON  
I
D
This is an active HI push button input which can be used to signal PWR_ON  
and PWR_OFF events to the CPU by controlling the ext_wakeup [pin4] and  
select contents of register 8H'88  
2
3
nTEST_JIG  
SPARE  
I
I
D
D
This is an active LOW input signal used for detecting an external HW event. The  
response is seen in the ext_wakeup [pin4] and select contents of register 8H'88  
This is an input signal used for detecting a external HW event. The response is  
seen in the ext_wakeup [pin4] and select contents of register 8H'88. The polarity  
on this pin is assignable  
4
EXT_WAKEUP  
O
D
This pin generates a single 10 ms pulse output to CPU in response to input  
from pins 1, 2, and 3. Flags CPU to interrogate register 8H'88  
5
6
7
8
9
FB1  
VIN  
I
I
A
Buck1 input feedback terminal  
Battery Input (Internal circuitry and LDO1-3 power input)  
LDO1 output  
PWR  
PWR  
PWR  
D
VOUT LDO1  
VOUT LDO2  
nRSTI  
O
O
I
LDO2 output  
Active low Reset pin. Signal used to reset the IC (by default is pulled high  
internally). Typically a push button reset.  
10  
11  
12  
13  
14  
GND1  
VREF  
G
O
O
O
I
G
Ground  
A
Bypass Cap. for the high internal impedance reference.  
VOUT LDO3  
VOUT LDO4  
VIN LDO4  
PWR  
PWR  
PWR  
LDO3 output  
LDO4 output  
Power input to LDO4, this can be connected to either from a 1.8V supply to  
main Battery supply.  
15  
16  
17  
VIN BUBATT  
VOUT LDO_RTC  
nBATT_FLT  
I
PWR  
PWR  
D
Back Up Battery input supply.  
O
O
LDO_RTC output supply to the RTC of the application processor.  
Main Battery fault output, indicates the main battery is low  
(discharged) or the dc source has been removed from the system. This gives  
the processor an indicator that the power will shut down. During this time the  
processor will operate from the back up coin cell.  
18  
19  
PGND2  
SW2  
G
O
G
Buck2 NMOS Power Ground  
Buck2 switcher output  
PWR  
(1) A: Analog Pin D: Digital Pin G: Ground Pin P: Power Pin I: Input Pin I/O: Input/Output Pin O: Output Pin  
Note: In this document, active-low logic items are prefixed with a lowercase "n".  
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PIN DESCRIPTIONS (continued)  
Pin No.  
20  
Name  
VIN Buck2  
SDA  
I/O  
Type(1)  
Description  
I
I/O  
I
PWR  
D
Battery input power to Buck2  
I2C Data (Bidirectional)  
I2C Clock  
21  
22  
SCL  
D
23  
FB2  
I
A
Buck2 input feedback terminal  
24  
nRSTO  
VOUT LDO5  
VIN LDO5  
VDDA  
O
O
I
D
Reset output from the PMIC to the processor  
25  
PWR  
PWR  
PWR  
A
LDO5 output  
26  
Power input to LDO5, this can be connected to VIN or to a separate 1.8V supply.  
Analog Power for VREF, BIAS  
27  
I
28  
FB3  
I
Buck3 Feedback  
29  
GPIO1 /  
nCHG_EN  
I/O  
D
General Purpose I/O / Ext. backup battery charger enable pin. This pin enables  
the main battery / DC source power to charge the backup battery. This pin  
toggled via the application processor. By grounding this pin the DC source  
continuously charges the backup battery  
30  
31  
32  
33  
34  
35  
GPIO2  
VIN Buck3  
SW3  
I/O  
I
D
PWR  
PWR  
G
General Purpose I/O  
Battery input power to Buck3  
Buck3 switcher output  
O
G
G
I
PGND3  
BGND1,2,3  
SYNC  
Buck3 NMOS Power Ground  
Bucks 1, 2 and 3 analog Ground  
G
D
Frequency Synchronization: Connection to an external clock signal PLL to  
synchronize the PMIC internal oscillator.  
Input Digital enable pin for the high voltage power domain supplies. Output from  
the Monahans processor.  
36  
SYS_EN  
I
D
Digital enable pin for the Low Voltage domain supplies. Output signal from the  
Monahans processor  
37  
38  
39  
40  
PWR_EN  
PGND1  
SW1  
I
D
G
O
I
G
Buck1 NMOS Power Ground  
Buck1 Switcher output  
PWR  
PWR  
VIN Buck1  
Battery input power to Buck1  
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam  
during storage or handling to prevent electrostatic damage to the MOS gates.  
Absolute Maximum Ratings(1)(2)  
All Inputs  
0.3V to +6.5V  
±0.3V  
GND to GND SLUG  
Junction Temperature (TJ-MAX  
Storage Temperature  
)
150°C  
65°C to +150°C  
3.2W  
Power Dissipation (TA = 70°C)(3)  
(3)  
Junction-to-Ambient Thermal Resistance θJA  
Maximum Lead Temp (Soldering)  
25°C/W  
260°C  
Human Body Model  
Machine Model  
2 kV  
ESD Rating(4)  
200V  
(1) Absolute Maximum Ratings are limits beyond which damage to the device may occur. Operating Ratings are conditions under which  
operation of the device is specified. Operating Ratings do not imply ensured performance limits. For specified performance limits and  
associated test conditions, see the Electrical Characteristics tables.  
(2) If Military/Aerospace specified devices are required, please contact the TI Sales Office/Distributors for availability and specifications.  
(3) In applications where high power dissipation and/or poor package thermal resistance is present, the maximum ambient temperature may  
have to be derated. Maximum ambient temperature (TA-MAX) is dependent on the maximum operating junction temperature (TJ-MAX-  
OP = 125°C), the maximum power dissipation of the device in the application (PD-MAX), and the junction-to ambient thermal resistance  
of the part/package in the application (θJA), as given by the following equation: TA-MAX = TJ-MAX-OP – (θJA x PD-MAX).  
(4) The Human body model is a 100 pF capacitor discharged through a 1.5 kresistor into each pin. (MIL-STD-883 3015.7) The machine  
model is a 200 pF capacitor discharged directly into each pin. (EAIJ).  
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Operating Ratings  
VIN  
2.7V to 5.5V  
1.74 to VIN  
VINLDO4, 5  
Junction Temperature (TJ)  
Operating Temperature (TA)  
Maximum Power Dissipation (TA = 70°C)(1)(2)  
40°C to +125°C  
40°C to +85°C  
2.2W  
(1) In applications where high power dissipation and/or poor package thermal resistance is present, the maximum ambient temperature may  
have to be derated. Maximum ambient temperature (TA-MAX) is dependent on the maximum operating junction temperature (TJ-MAX-  
OP = 125°C), the maximum power dissipation of the device in the application (PD-MAX), and the junction-to ambient thermal resistance  
of the part/package in the application (θJA), as given by the following equation: TA-MAX = TJ-MAX-OP – (θJA x PD-MAX).  
(2) Junction-to-ambient thermal resistance (θJA) is taken from a thermal modeling result, performed under the conditions and guidelines set  
forth in the JEDEC standard JESD51–7. The test board is a 4-layer FR-4 board measuring 102 mm x 76 mm x 1.6 mm with a 2x1 array  
of thermal vias. The ground plane on the board is 50 mm x 50 mm. Thickness of copper layers are 36 µm/1.8 µm/18 µm/36 µm (1.5 oz/1  
oz/1 oz/1.5 oz). Ambient temperature in simulation is 22°C, still air. Power dissipation is 1W. Junction-to-ambient thermal resistance is  
highly application and board-layout dependent. In applications where high maximum power dissipation exists, special care must be paid  
to thermal dissipation issues in board design. The value of θJA of this product can vary significantly, depending on PCB material, layout,  
and environmental conditions. In applications where high maximum power dissipation exists (high VIN, high IOUT), special care must be  
paid to thermal dissipation issues. For more information on these topics, see Application Note AN-1187 Leadless Leadframe Package  
(LLP)(SNOA401) and the Power Efficiency and Power Dissipation sections of this datasheet.  
General Electrical Characteristics  
Typical values and limits appearing in normal type apply for TJ = 25°C. Limits appearing in boldface type apply over the  
entire junction temperature range for operation, 40°C to +125°C(1)(2)(3)  
Symbol  
VIN, VDDA, VIN Buck1, 2 and 3  
VINLDO4, VINLDO5  
TSD  
Parameter  
Battery Voltage  
Test Conditions  
Min  
2.7  
Typ  
3.6  
3.6  
160  
20  
Max  
5.5  
Unit  
V
Power Supply for LDO 4 and 5  
Thermal Shutdown(4)  
1.74  
VIN  
V
Temperature  
Hysteresis  
°C  
(1) All voltages are with respect to the potential at the GND pin.  
(2) All limits specified at room temperature (standard typeface) and at temperature extremes (bold typeface). All room temperature limits are  
production tested, ensured through statistical analysis or ensured by design. All limits at temperature extremes are ensured via  
correlation using standard Statistical Quality Control (SQC) methods. All limits are used to calculate Average Outgoing Quality Level  
(AOQL).  
(3) No input supply should be higher then VDDA  
(4) This electrical specification is ensured by design.  
Supply Specifications(1)(2)  
VOUT (Volts)  
IMAX: Maximum Current  
Current (mA)  
Supply  
Range  
(V)  
Resolution  
(mV)  
N/A  
LDO_RTC  
LDO1 (VCC_MVT)  
LDO2  
2.8V  
30 mA dc source 10 mA backup source  
1.7 to 2.0  
1.8 to 3.3  
1.8 to 3.3  
1.0 to 3.3  
0.850 to 1.5  
0.725 to 1.5  
0.8 to 3.3  
0.8 to 3.3  
25  
300  
150  
100  
LDO3  
100  
150  
LDO4  
50-600  
25  
150  
LDO5 (VCC_SRAM)  
BUCK1 (VCC_APPS)  
BUCK2  
400  
25  
1600  
1600  
1600  
50-600  
50-600  
BUCK3  
(1) All voltages are with respect to the potential at the GND pin.  
(2) The Human body model is a 100 pF capacitor discharged through a 1.5 kresistor into each pin. (MIL-STD-883 3015.7) The machine  
model is a 200 pF capacitor discharged directly into each pin. (EAIJ).  
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Default Voltage Option(1)(2)(3)  
Version  
LP3972SQ-A514  
LP3972SQ-A413  
Enable  
Version A  
Version A  
LDO_RTC  
2.8  
1.8  
1.8D  
3D  
2.8  
1.8  
1.8D  
3D  
LDO1  
SYS_EN  
SYS_EN  
SYS_EN  
SYS_EN  
PWR_EN  
PWR_EN  
SYS_EN  
SYS_EN  
SYS_EN  
SYS_EN  
SYS_EN  
SYS_EN  
PWR_EN  
PWR_EN  
SYS_EN  
SYS_EN  
LDO2  
LDO3  
LDO4  
3D  
2.8D  
1.4  
1.4  
3
LDO5  
1.4  
1.4  
3.3  
1.8  
BUCK1  
BUCK2  
BUCK3  
Version  
Enable  
LDO_RTC  
LDO1  
1.8  
LP3972SQ-E514  
LP3972SQ-I514  
Version E  
Version I  
2.8  
1.8  
1.8E  
3D  
2.8  
1.8  
1.8E  
3E  
SYS_EN  
SYS_EN  
SYS_EN  
SYS_EN  
PWR_EN  
PWR_EN  
SYS_EN  
SYS_EN  
SYS_EN  
SYS_EN  
SYS_EN  
SYS_EN  
PWR_EN  
PWR_EN  
SYS_EN  
SYS_EN  
LDO2  
LDO3  
LDO4  
3D  
3E  
LDO5  
1.4  
1.4  
3.3  
1.8  
1.4  
1.4  
3.3  
1.8  
BUCK1  
BUCK2  
BUCK3  
Version  
Enable  
LDO_RTC  
LDO1  
LP3972SQ-I414  
LP3972SQ-0514  
Version I  
Version 0  
2.8  
1.8  
1.8E  
3E  
Tracking enabled  
SYS_EN  
3.3 w/ tracking  
SYS_EN  
SYS_EN  
SYS_EN  
SYS_EN  
PWR_EN  
PWR_EN  
SYS_EN  
SYS_EN  
1.8  
1.8E  
3.3E  
3E  
LDO2  
SYS_EN  
LDO3  
SYS_EN  
LDO4  
3E  
SYS_EN  
LDO5  
1.4  
1.4  
3.0  
1.8  
PWR_EN  
PWR_EN  
SYS_EN  
1.4  
BUCK1  
BUCK2  
BUCK3  
Version  
Enable  
LDO_RTC  
LDO1  
1.4  
3.3  
SYS_EN  
1.8  
LP3972SQ-5810  
Version 5  
2.8  
1.8  
SYS_EN  
SYS_EN  
SYS_EN  
PWR_EN  
PWR_EN  
PWR_EN  
SYS_EN  
SYS_EN  
LDO2  
1.8E  
2.5E  
1.3E  
1.1  
LDO3  
LDO4  
LDO5  
BUCK1  
BUCK2  
BUCK3  
1.35  
1.2  
1.8  
(1) All voltages are with respect to the potential at the GND pin.  
(2) The Human body model is a 100 pF capacitor discharged through a 1.5 kresistor into each pin. (MIL-STD-883 3015.7) The machine  
model is a 200 pF capacitor discharged directly into each pin. (EAIJ).  
(3) E = Regulator is ENABLED during startup. D = Regulator is DISABLED during startup.  
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LDO RTC  
Unless otherwise noted, VIN = 3.6V, CIN = 1.0 µF, COUT = 0.47 µF, COUT (VRTC) = 1.0 µF ceramic. Typical values and limits  
appearing in normal type apply for TJ = 25°C. Limits appearing in boldface type apply over the entire junction temperature  
range for operation, 40°C to +125°C(1)(2)(3)(4)  
Symbol  
Parameter  
Test Conditions  
Min  
Typ  
Max  
2.968  
0.15  
Unit  
V
VOUT Accuracy Output Voltage Accuracy  
VIN Connected, Load Current = 1 mA  
VIN = (VOUT nom + 1.0V) to 5.5V(5)  
Load Current = 1 mA  
2.632  
2.8  
ΔVOUT  
Line Regulation  
Load Regulation  
%/V  
From Main Battery  
Load Current = 1 mA to 30 mA  
0.05  
0.5  
%/mA  
From Backup Battery, VIN = 3.0V  
Load Current = 1 mA to 10 mA  
ISC  
Short Circuit Current Limit  
From Main Battery  
VIN = VOUT +0.3V to 5.5V  
100  
30  
mA  
From Backup Battery  
Load Current = 10 mA  
IOUT = 0 mA  
VIN - VOUT  
IQ_Max  
TP1  
Dropout Voltage  
375  
mV  
µA  
V
Maximum Quiescent Current  
30  
RTC LDO Input Switched from  
Main Battery to Backup Battery  
VIN Falling  
2.9  
TP2  
CO  
RTC LDO Input Switched from  
Backup Battery to Main Battery  
VIN Rising  
3.0  
1.0  
V
Output Capacitor  
Capacitance for Stability  
ESR  
0.7  
5
µF  
500  
mΩ  
(1) All voltages are with respect to the potential at the GND pin.  
(2) All limits specified at room temperature (standard typeface) and at temperature extremes (bold typeface). All room temperature limits are  
production tested, ensured through statistical analysis or ensured by design. All limits at temperature extremes are ensured via  
correlation using standard Statistical Quality Control (SQC) methods. All limits are used to calculate Average Outgoing Quality Level  
(AOQL).  
(3) Dropout voltage is the input-to-output voltage difference at which the output voltage is 100 mV below its nominal value.  
(4) LDO_RTC voltage can track LDO3 voltage. LP3972 has a tracking function (nIO_TRACK). When enabled, LDO_RTC voltage will track  
LDO3 voltage within 200mV down to 2.8V when LDO3 is enabled  
(5) VIN minimum for line regulation values is 2.7V for LDOs 1–3 and 1.8V for LDOs 4 and 5. Condition does not apply to input voltages  
below the minimum input operating voltage.  
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LDOs 1 to 5  
Unless otherwise noted, VIN = 3.6V, CIN = 1.0 µF, COUT = 0.47 µF, COUT (VRTC) = 1.0 µF ceramic. Typical values and limits  
appearing in normal type apply for TJ = 25°C. Limits appearing in boldface type apply over the entire junction temperature  
range for operation, 40°C to +125°C(1)(2)(3)(4)(5)(6)(7)  
Symbol  
VOUT Accuracy Output Voltage Accuracy  
(Default VOUT  
Parameter  
Test Conditions  
Load Current = 1 mA  
Min  
Typ  
Max  
3
Unit  
3  
%
)
ΔVOUT  
Line Regulation  
VIN =3.1V to 5.0V(5)  
,
0.15  
%/V  
Load Current = 1 mA  
Load Regulation  
VIN = 3.6V,  
0.011  
%/mA  
Load Current = 1 mA to IMAX  
ISC  
Short Circuit Current Limit  
LDO1–4, VOUT = 0V  
400  
500  
mA  
LDO5, VOUT = 0V  
VIN - VOUT  
PSRR  
IQ  
Dropout Voltage  
Load Current = 50 mA(3)  
150  
mV  
dB  
Power Supply Ripple Rejection f = 10 kHz, Load Current = IMAX  
45  
40  
Quiescent Current "On"  
Quiescent Current "On"  
Quiescent Current "Off"  
Turn On Time  
IOUT = 0 mA  
IOUT = IMAX  
60  
µA  
EN is de-asserted  
Start up from Shut-down  
0.03  
300  
0.47  
TON  
µsec  
µF  
COUT  
Output Capacitor  
Capacitance for Stability  
0°C TJ 125°C  
0.33  
40°C TJ 125°C  
0.68  
5
1.0  
ESR  
500  
mΩ  
(1) All voltages are with respect to the potential at the GND pin.  
(2) All limits specified at room temperature (standard typeface) and at temperature extremes (bold typeface). All room temperature limits are  
production tested, ensured through statistical analysis or ensured by design. All limits at temperature extremes are ensured via  
correlation using standard Statistical Quality Control (SQC) methods. All limits are used to calculate Average Outgoing Quality Level  
(AOQL).  
(3) Dropout voltage is the input-to-output voltage difference at which the output voltage is 100 mV below its nominal value.  
(4) LDO_RTC voltage can track LDO3 voltage. LP3972 has a tracking function (nIO_TRACK). When enabled, LDO_RTC voltage will track  
LDO3 voltage within 200mV down to 2.8V when LDO3 is enabled  
(5) VIN minimum for line regulation values is 2.7V for LDOs 1–3 and 1.8V for LDOs 4 and 5. Condition does not apply to input voltages  
below the minimum input operating voltage.  
(6) An increase in the load current results in a slight decrease in the output voltage and vice versa.  
(7) Dropout voltage is the input-to-output voltage difference at which the output voltage is 100 mV below its nominal value. This  
specification does not apply for input voltages below 2.7V for LDOs 1–3 and 1.8V for LDOs 4 and 5.  
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LDO Dropout Voltage vs. Load Current Collect Data For All LDOs  
Dropout Voltage vs.  
Load Current  
Change in Output Voltage  
vs. Load Current  
300  
250  
200  
150  
100  
50  
200  
150  
100  
50  
REG1 3.3V OUTPUT  
REG2 2.5V OUTPUT  
REG3 1.3V OUTPUT  
0
REG1 3.3V OUTPUT  
-50  
-100  
V
= 3.6V  
200  
IN  
0
0
200  
400  
600  
800 1000 1200  
0
400  
600  
800 1000 1200  
LOAD CURRENT (mA)  
LOAD CURRENT (mA)  
Figure 3.  
Figure 4.  
LDO1 Line Regulation  
VOUT = 1.8 volts VIN 3 to 4 volts Load = 100 mA  
LDO1 Load Transient  
VIN = 4.1 volts VOUT = 1.8 volts no-load-100 mA  
4.03 ms  
4.0 ms  
Figure 5.  
Figure 6.  
Enable Start-up time (LDO1)  
LDO1 Channel 2 LDO4 Channel 1 Sys_enable from 0 volts Load = 100 mA  
4.03 ms  
Figure 7.  
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Buck Converters SW1, SW2, SW3  
Unless otherwise noted, VIN = 3.6V, CIN = 10 µF, COUT = 10 µF, LOUT = 2.2 µH ceramic. Typical values and limits appearing in  
normal type apply for TJ = 25°C. Limits appearing in boldface type apply over the entire junction temperature range for  
operation, 40°C to +125°C(1)(2)(3)(4)  
Symbol  
VOUT  
Parameter  
Output Voltage Accuracy  
Efficiency  
Test Conditions  
Min  
Typ  
Max  
Unit  
%
Default VOUT  
3  
+3  
Eff  
Load Current = 500 mA  
95  
0.1  
13  
%
ISHDN  
Shutdown Supply Current  
Sync Mode Clock Frequency  
Internal Oscillator Frequency  
Peak Switching Current Limit  
Quiescent Current "On"  
EN is de-asserted  
µA  
Synchronized from 13 MHz System Clock  
10.4  
15.6  
2.4  
MHz  
MHz  
A
fOSC  
IPEAK  
IQ  
2.0  
2.1  
21  
No Load PFM Mode  
No Load PWM Mode  
µA  
200  
240  
200  
500  
RDSON (P)  
RDSON (N)  
TON  
Pin-Pin Resistance PFET  
Pin-Pin Resistance NFET  
Turn On Time  
mΩ  
mΩ  
µsec  
µF  
Start up from Shut-down  
Capacitance for Stability  
Capacitance for Stability  
CIN  
Input Capacitor  
8
8
CO  
Output Capacitor  
µF  
(1) All voltages are with respect to the potential at the GND pin.  
(2) All limits specified at room temperature (standard typeface) and at temperature extremes (bold typeface). All room temperature limits are  
production tested, ensured through statistical analysis or ensured by design. All limits at temperature extremes are ensured via  
correlation using standard Statistical Quality Control (SQC) methods. All limits are used to calculate Average Outgoing Quality Level  
(AOQL).  
(3) The input voltage range recommended for ideal applications performance for the specified output voltages is given below:VIN = 2.7V to  
5.5V for 0.80V < VOUT < 1.8VVIN = (VOUT+ 1V) to 5.5V for 1.8V VOUT 3.3V  
(4) Test condition: for VOUT less than 2.7V, VIN = 3.6V; for VOUT greater than or equal to 2.7V, VIN = VOUT+ 1V.  
Buck1 Output Efficiency vs. Load Current Varied from 1mA to 1.5 Amps  
VIN = 3, 3.5 volts VOUT = 1.4 volts Forced PWM  
VIN = 4.0-4.5 volts VOUT = 1.4 volts Forced PWM  
100.00  
90.00  
V
IN  
= 3V  
V
= 4V  
IN  
80.00  
60.00  
40.00  
20.00  
0.00  
72.00  
54.00  
36.00  
18.00  
0.00  
V
= 3.5V  
IN  
V
= 4.5V  
IN  
1
1e1  
1e2  
1e3  
1e4  
1
1e1  
1e2  
1e3  
1e4  
OUTPUT CURRENT (mA)  
OUTPUT CURRENT (mA)  
Figure 8.  
Figure 9.  
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Line Transient Response  
VIN = 3 – 3.6 V, VOUT = 1.2 V, 250 mA load  
VIN = 3, 3.5 volts VOUT = 1.4 volts Forced PWM  
90.00  
72.00  
54.00  
36.00  
18.00  
0.00  
V
= 5.5V  
IN  
V
= 5V  
IN  
4.03 ms  
1
1e1  
1e2  
1e3  
1e4  
OUTPUT CURRENT (mA)  
Figure 10.  
Figure 11.  
Mode Change  
Load transients 20 mA to 560 mA  
VOUT = 1.4 volts [PFM to PWM] VIN = 4.1 volts  
Load Transient  
3.6 VIN, 3.3 VOUT, 0 – 100 mA load  
4.03 ms  
4.0 ms  
Figure 12.  
Figure 13.  
Startup  
Startup into PWM Mode 980 mA [channel 2]  
VOUT = 1.4 volts VIN = 4.1 volts  
4.03 ms  
Figure 14.  
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Back-Up Charger Electrical Characteristics  
Unless otherwise noted, VIN = VBATT = 3.6V. Typical values and limits appearing in normal type apply for TJ = 25°C. Limits  
appearing in boldface type apply over the entire junction temperature range for operation, 40°C to +125°C(1)(2)(3)  
Symbol  
VIN  
Parameter  
Test Conditions  
Min  
3.3  
Typ  
Max  
5.5  
Unit  
V
Operational Voltage Range  
Voltage at VIN  
IOUT  
Backup Battery Charging Current VIN = 3.6V, Backup_Bat = 2.5V, Backup  
Battery Charger Enabled(3)  
190  
3.1  
9
µA  
VOUT  
Charger Termination Voltage  
VIN = 5.0V Backup Battery Charger Enabled.  
Programmable  
2.91  
V
Backup Battery Charger Short  
Circuit Current  
Backup_Bat = 0V, Backup Battery Charger  
Enabled  
mA  
dB  
PSRR  
Power Supply Ripple Rejection  
Ratio  
I
OUT 50 µA, VOUT = 3.15V  
15  
VOUT + 0.4 VBATT = VIN 5.0V  
f < 10 kHz  
IQ  
Quiescent Current  
IOUT < 50 µA  
25  
µA  
µF  
COUT  
Output Capacitance  
Output Capacitor ESR  
0 µA IOUT 100 µA  
0.1  
5
500  
mΩ  
(1) All voltages are with respect to the potential at the GND pin.  
(2) All limits specified at room temperature (standard typeface) and at temperature extremes (bold typeface). All room temperature limits are  
production tested, ensured through statistical analysis or ensured by design. All limits at temperature extremes are ensured via  
correlation using standard Statistical Quality Control (SQC) methods. All limits are used to calculate Average Outgoing Quality Level  
(AOQL).  
(3) Back-up battery charge current is programmable via the I2C compatible interface. Refer to the Application Section for more information.  
LP3972 Battery Switch Operation  
The LP3972 has provisions for two battery connections, the main battery VBAT and Backup Battery.  
The function of the battery switch is to connect power to the LDO_RTC from the appropriate battery, depending  
on conditions described below:  
If only the backup battery is applied, the switch will automatically connect the LDO_RTC power to this battery.  
If only the main battery is applied, the switch will automatically connect the LDO_RTC power to this battery  
If both batteries are applied, and the main battery is sufficiently charged (VBAT > 3.1V), the switch will  
automatically connect the LDO_RTC power to the main battery.  
As the main battery is discharged a separate circuit called nBATT_FLT will warn the system. Then if no action  
is taken to restore the charge on the main battery, and discharging is continued the battery switch will  
disconnect the input of the LDO_RTC from the main battery and connect to the backup battery.  
The main battery voltage at which the LDO_RTC is switched over from main to backup battery is 2.8V  
typically.  
There is a hysteric voltage in this switch operation, thus the LDO_RTC will not be reconnected to main  
battery until main battery voltage is greater than 3.1V typically.  
The system designer may wish to disable the battery switch when only a main battery is used. This is  
accomplished by setting the "no back up battery bit" in the control register 8h’0B bit 7 NBUB. With this bit set  
to "1", the above described switching will not occur, that is the LDO_RTC will remain connected to the main  
battery even as it is discharged below the 2.9V threshold. The Backup battery input should also be connected  
to main battery.  
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Logic Inputs and Outputs DC Operating Conditions(1)  
Logic Inputs (SYS_EN, PWR_EN, SYNC, nRSTI, PWR_ON, nTEST_JIG, SPARE and GPI's)  
Symbol  
VIL  
Parameter  
Low Level Input Voltage  
High Level Input Voltage  
Input Leakage Current  
Test Conditions  
Min  
Max  
0.5  
Unit  
V
VIH  
V
RTC 0.5V  
V
ILEAK  
1  
+1  
µA  
(1) All voltages are with respect to the potential at the GND pin.  
Logic Outputs (nRSTO, EXT_WAKEUP and GPO's)  
Symbol  
VOL  
Parameter  
Output Low Level  
Test Conditions  
Load = +0.2 mA = IOL Max  
Load = 0.1 mA = IOL Max  
VON = VIN  
Min  
Max  
0.5  
Unit  
V
VOH  
Output High Level  
V
RTC 0.5V  
V
ILEAK  
Output Leakage Current  
+5  
µA  
Logic Output (nBATT_FLT)  
Symbol  
Parameter  
Test Conditions  
Min  
2.4  
Typ  
2.8  
Max  
Unit  
nBATT_FLT Threshold Voltage  
Programmable via Serial Interface  
Default = 2.8V  
3.4  
V
VOL  
Output Low Level  
Load = +0.4 mA = IOL Max  
0.5  
V
V
VOH  
Output High Level  
Input Leakage Current  
Load = 0.2 mA = IOH Max  
VRTC 0.5V  
ILEAK  
+5  
µA  
I2C Compatible Serial Interface Electrical Specifications (SDA and SCL)  
Unless otherwise noted, VIN = 3.6V. Typical values and limits appearing in normal type apply for TJ = 25°C. Limits appearing  
in boldface type apply over the entire junction temperature range for operation, 40°C to +125°C(1)(2)(3)  
Symbol  
Parameter  
Low Level Input Voltage  
Test Conditions  
See(4)  
Min  
0.5  
0.7 VRTC  
0
Typ  
Max  
Unit  
VIL  
VIH  
VOL  
IOL  
0.3 VRTC  
VRTC  
V
High Level Input Voltage  
Low Level Output Voltage  
Low Level Output Current  
Clock Frequency  
See(4)  
See(4)  
VOL = 0.4V(4)  
See(4)  
See(4)  
See(4)  
See(4)  
See(4)  
See(4)  
See(4)  
See(4)  
See(4)  
See(4)  
0.2 VTRC  
3.0  
mA  
kHz  
µs  
µs  
µs  
µs  
µs  
µs  
ns  
FCLK  
400  
tBF  
Bus-Free Time Between Start and Stop  
Hold Time Repeated Start Condition  
CLK Low Period  
1.3  
0.6  
1.3  
0.6  
0.6  
0
tHOLD  
tCLKLP  
tCLKHP  
tSU  
CLK High Period  
Set Up Time Repeated Start Condition  
Data Hold Time  
tDATAHLD  
tCLKSU  
TSU  
Data Set Up Time  
100  
0.6  
Set Up Time for Start Condition  
µs  
ns  
TTRANS  
Maximum pulse width of spikes that must be  
suppressed by the input filter of both DATA and  
CLK signals  
50  
(1) All voltages are with respect to the potential at the GND pin.  
(2) All limits specified at room temperature (standard typeface) and at temperature extremes (bold typeface). All room temperature limits are  
production tested, ensured through statistical analysis or ensured by design. All limits at temperature extremes are ensured via  
correlation using standard Statistical Quality Control (SQC) methods. All limits are used to calculate Average Outgoing Quality Level  
(AOQL).  
(3) The I2C signals behave like open-drain outputs and require an external pull-up resistor on the system module in the 2 kto 20 kΩ  
range.  
(4) This electrical specification is ensured by design.  
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Detailed Description  
Buck Converter Operation  
DEVICE INFORMATION  
The LP3972 includes three high efficiency step down DC-DC switching buck converters. Using a voltage mode  
architecture with synchronous rectification, the buck converters have the ability to deliver up to 1600 mA  
depending on the input voltage, output voltage, ambient temperature and the inductor chosen.  
There are three modes of operation depending on the current required - PWM, PFM, and shutdown. The device  
operates in PWM mode at load currents of approximately 100 mA or higher, having voltage tolerance of ±3%  
with 95% efficiency or better. Lighter load currents cause the device to automatically switch into PFM for reduced  
current consumption. Shutdown mode turns off the device, offering the lowest current consumption (IQ, SHUTDOWN  
= 0.01 µA typ).  
Additional features include soft-start, under voltage protection, current overload protection, and thermal shutdown  
protection.  
The part uses an internal reference voltage of 0.5V. It is recommended to keep the part in shutdown until the  
input voltage is 2.7V or higher.  
CIRCUIT OPERATION  
The buck converter operates as follows. During the first portion of each switching cycle, the control block turns  
on the internal PFET switch. This allows current to flow from the input through the inductor to the output filter  
capacitor and load. The inductor limits the current to a ramp with a slope of (VIN–VOUT)/L, by storing energy in a  
magnetic field.  
During the second portion of each cycle, the controller turns the PFET switch off, blocking current flow from the  
input, and then turns the NFET synchronous rectifier on. The inductor draws current from ground through the  
NFET to the output filter capacitor and load, which ramps the inductor current down with a slope of –VOUT/L.  
The output filter stores charge when the inductor current is high, and releases it when inductor current is low,  
smoothing the voltage across the load.  
The output voltage is regulated by modulating the PFET switch on time to control the average current sent to the  
load. The effect is identical to sending a duty-cycle modulated rectangular wave formed by the switch and  
synchronous rectifier at the SW pin to a low-pass filter formed by the inductor and output filter capacitor. The  
output voltage is equal to the average voltage at the SW pin.  
PWM OPERATION  
During PWM operation the converter operates as a voltage mode controller with input voltage feed forward. This  
allows the converter to achieve good load and line regulation. The DC gain of the power stage is proportional to  
the input voltage. To eliminate this dependence, feed forward inversely proportional to the input voltage is  
introduced.  
While in PWM (Pulse Width Modulation) mode, the output voltage is regulated by switching at a constant  
frequency and then modulating the energy per cycle to control power to the load. At the beginning of each clock  
cycle the PFET switch is turned on and the inductor current ramps up until the comparator trips and the control  
logic turns off the switch. The current limit comparator can also turn off the switch in case the current limit of the  
PFET is exceeded. Then the NFET switch is turned on and the inductor current ramps down. The next cycle is  
initiated by the clock turning off the NFET and turning on the PFET.  
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V
SW  
2V/DIV  
I
L
200 mA/DIV  
V
V
= 3.6V  
IN  
I
= 400 mA  
OUT  
= 1.5V  
OUT  
V
OUT  
10 mV/DIV  
AC Coupled  
TIME (200 ns/DIV)  
Figure 15. Typical PWM Operation  
Internal Synchronous Rectification  
While in PWM mode, the converters uses an internal NFET as a synchronous rectifier to reduce rectifier forward  
voltage drop and associated power loss. Synchronous rectification provides a significant improvement in  
efficiency whenever the output voltage is relatively low compared to the voltage drop across an ordinary rectifier  
diode.  
Current Limiting  
A current limit feature allows the converters to protect itself and external components during overload conditions.  
PWM mode implements current limiting using an internal comparator that trips at 2.0 A (typ). If the output is  
shorted to ground the device enters a timed current limit mode where the NFET is turned on for a longer duration  
until the inductor current falls below a low threshold, ensuring inductor current has more time to decay, thereby  
preventing runaway.  
PFM OPERATION  
At very light loads, the converter enters PFM mode and operates with reduced switching frequency and supply  
current to maintain high efficiency.  
The part will automatically transition into PFM mode when either of two conditions occurs for a duration of 32 or  
more clock cycles:  
1. The inductor current becomes discontinuous.  
2. The peak PMOS switch current drops below the IMODE level, (Typically IMODE < 30 mA + VIN/42).  
2V/DIV  
V
SW  
I
L
200 mA/DIV  
VIN = 3.6V  
I
= 20 mA  
OUT  
VOUT = 1.5V  
V
OUT  
20 mV/DIV  
AC Coupled  
TIME (4 ms/DIV)  
Figure 16. Typical PFM Operation  
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During PFM operation, the converter positions the output voltage slightly higher than the nominal output voltage  
during PWM operation, allowing additional headroom for voltage drop during a load transient from light to heavy  
load. The PFM comparators sense the output voltage via the feedback pin and control the switching of the output  
FETs such that the output voltage ramps between <0.6% and <1.7% above the nominal PWM output voltage. If  
the output voltage is below the "high" PFM comparator threshold, the PMOS power switch is turned on. It  
remains on until the output voltage reaches the ‘high’ PFM threshold or the peak current exceeds the IPFM level  
set for PFM mode. The typical peak current in PFM mode is: IPFM = 112 mA + VIN/27. Once the PMOS power  
switch is turned off, the NMOS power switch is turned on until the inductor current ramps to zero. When the  
NMOS zero-current condition is detected, the NMOS power switch is turned off. If the output voltage is below the  
‘high’ PFM comparator threshold (see Figure 17), the PMOS switch is again turned on and the cycle is repeated  
until the output reaches the desired level. Once the output reaches the ‘high’ PFM threshold, the NMOS switch is  
turned on briefly to ramp the inductor current to zero and then both output switches are turned off and the part  
enters an extremely low power mode. Quiescent supply current during this ‘sleep’ mode is 21 µA (typ), which  
allows the part to achieve high efficiencies under extremely light load conditions. When the output drops below  
the ‘low’ PFM threshold, the cycle repeats to restore the output voltage (average voltage in PFM mode) to  
<1.15% above the nominal PWM output voltage. If the load current should increase during PFM mode (see  
Figure 17) causing the output voltage to fall below the ‘low2’ PFM threshold, the part will automatically transition  
into fixed-frequency PWM mode. Typically when VIN = 3.6V the part transitions from PWM to PFM mode at 100  
mA output current.  
High PFM Threshold  
PFM Mode at Light Load  
~1.017*Vout  
Load current  
increases  
Low1 PFM Threshold  
~1.006*Vout  
Current load  
increases,  
draws Vout  
towards  
Low2 PFM  
Threshold  
High PFM  
Voltage  
Threshold  
reached,  
go into  
Nfet on  
drains  
conductor  
current  
until  
I inductor=0  
Low PFM  
Threshold,  
turn on  
Pfet on  
until  
Ipfm limit  
reached  
PFET  
Low2 PFM Threshold  
Vout  
sleep mode  
PWM Mode at  
Moderate to Heavy  
Loads  
Low2 PFM Threshold,  
switch back to PWMmode  
Figure 17. Operation in PFM Mode and Transfer to PWM Mode  
SHUTDOWN MODE  
During shutdown the PFET switch, reference, control and bias circuitry of the converters are turned off. The  
NFET switch will be open in shutdown to discharge the output. When the converter is enabled, EN, soft start is  
activated. It is recommended to disable the converter during the system power up and undervoltage conditions  
when the supply is less than 2.7V.  
SOFT START  
The buck converter has a soft-start circuit that limits in-rush current during start-up. During start-up the switch  
current limit is increased in steps. Soft start is activated only if EN goes from logic low to logic high after VIN  
reaches 2.7V. Soft start is implemented by increasing switch current limit in steps of 213 mA, 425 mA, 850 mA  
and 1700 mA (typ. Switch current limit). The start-up time thereby depends on the output capacitor and load  
current demanded at start-up. Typical start-up times with 10 µF output capacitor and 1000 mA load current is 390  
µs and with 1 mA load current it is 295 µs.  
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LDO - LOW DROP OUT OPERATION  
The LP3972 can operate at 100% duty cycle (no switching; PMOS switch completely on) for low drop out support  
of the output voltage. In this way the output voltage will be controlled down to the lowest possible input voltage.  
When the device operates near 100% duty cycle, output voltage ripple is approximately 25 mV. The minimum  
input voltage needed to support the output voltage is  
VIN, MIN = ILOAD * (RDSON, PFET + RINDUCTOR) + VOUT  
where  
ILOAD = Load Current  
RDSON, PFET = Drain to source resistance of PFET switch in the triode region  
RINDUCTOR = Inductor resistance  
(1)  
SPREAD SPECTRUM FEATURE  
Periodic switching in the buck regulator is inherently a noisier function block compared to an LDO. It can be  
challenging in some critical applications to comply with stringent regulatory standards or simply to minimize  
interference to sensitive circuits in space limited portable systems. The regulator’s switching frequency and  
harmonics can cause "noise" in the signal spectrum. The magnitude of this noise is measured by its power  
spectral density. The power spectral density of the switching frequency, FC, is one parameter that system  
designers want to be as low as practical to reduce interference to the environment and subsystems within their  
products. The LP3972 has a user selectable function on chip, wherein a noise reduction technique known as  
"spread spectrum" can be employed to ease customer’s design and production issues.  
The principle behind spread spectrum is to modulate the switching frequency slightly and slowly, and spread the  
signal frequency over a broader bandwidth. Thus, its power spectral density becomes attenuated, and the  
associated interference electro-magnetic energy is reduced. The clock used to modulate the LP3972 buck  
regulator can be used as a spread spectrum clock via 2 I2C control register (System Control Register 1 (SCR1)  
8h’80) bits bk_ssen, and slomod. With this feature enabled, the intense energy of the clock frequency can be  
spread across a small band of frequencies in the neighborhood of the center frequency. The results in a  
reduction of the peak energy!  
The LP3972 spread spectrum clock uses a triangular modulation profile with equal rise and fall slopes. The  
modulation has the following characteristics:  
The center frequency: FC = 2 MHz, and  
The modulating frequency, fM = 6.8 kHz or 12 kHz.  
Peak frequency deviation: Δ_f = ±100 kHz (or ±5%)  
Modulation index β = Δ_f/fM = 14.7 or 8.3  
Switching Energy RBW = 300 Hz  
0
-10  
-20  
-30  
-40  
-50  
-60  
2040  
2060  
2080  
2100  
2120  
2140  
FREQUENCY (kHz)  
Figure 18.  
18  
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I2C Compatible Interface  
I2C DATA VALIDITY  
The data on SDA line must be stable during the HIGH period of the clock signal (SCL). In other words, state of  
the data line can only be changed when CLK is LOW.  
SCL  
SDA  
data  
change  
allowed  
data valid  
data  
change  
allowed  
data  
change  
allowed  
data valid  
Figure 19.  
I2C START and STOP CONDITIONS  
START and STOP bits classify the beginning and the end of the I2C session. START condition is defined as SDA  
signal transitioning from HIGH to LOW while SCL line is HIGH. STOP condition is defined as the SDA  
transitioning from LOW to HIGH while SCL is HIGH. The I2C master always generates START and STOP bits.  
The I2C bus is considered to be busy after START condition and free after STOP condition. During data  
transmission, I2C master can generate repeated START conditions. First START and repeated START  
conditions are equivalent, function-wise.  
SDA  
SCL  
S
P
START condition  
STOP condition  
Figure 20.  
TRANSFERRING DATA  
Every byte put on the SDA line must be eight bits long, with the most significant bit (MSB) being transferred first.  
The number of bytes that can be transmitted per transfer is unrestricted. Each byte of data has to be followed by  
an acknowledge bit. The acknowledge related clock pulse is generated by the master. The transmitter releases  
the SDA line (HIGH) during the acknowledge clock pulse. The receiver must pull down the SDA line during the  
9th clock pulse, signifying an acknowledge. A receiver which has been addressed must generate an  
acknowledge after each byte has been received.  
After the START condition, a chip address is sent by the I2C master. This address is seven bits long followed by  
an eighth bit which is a data direction bit (R/W). The LP3972 address is 34h. For the eighth bit, a "0" indicates a  
WRITE and a "1" indicates a READ. The second byte selects the register to which the data will be written. The  
third byte contains data to write to the selected register.  
I2C CHIP ADDRESS - 7h'34  
MSB  
ADR6  
Bit7  
ADR5  
Bit6  
ADR4  
Bit5  
ADR3  
Bit4  
ADR2  
Bit3  
ADR1  
Bit2  
ADR0  
Bit1  
R/W  
Bit0  
0
1
1
0
1
0
0
R/W  
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Write Cycle  
start  
msb Chip Address lsb  
w
ack  
Msb Register Add lsb  
ack  
msb  
DATA  
lsb  
ack stop  
SCL  
SDA  
start  
Id = 34h  
w
ack  
addr = 02h  
ack  
address h‘02 data  
ack stop  
Figure 21. Write cycle  
Read Cycle  
When a READ function is to be accomplished, a WRITE function must precede the READ function as follows.  
start msb Chip Address lsb  
w
msb Register Add lsb  
rs  
msb Chip Address lsb  
r
msb  
DATA  
lsb  
stop  
ack  
ack  
ack  
ack  
SCL  
SDA  
start  
Id = 34h  
w
ack  
addr = 00h  
ack rs  
Id = 34h  
r
ack  
Address h‘00 data  
ack stop  
w = write (SDA = "0")  
r = read (SDA = "1")  
ack = acknowledge (SDA pulled down by either master or slave)  
rs = repeated start  
id = 34h (Chip Address)  
Figure 22. Read Cycle  
DATA OUTPUT  
BY TRANSMITTER  
DATA OUTPUT  
BY RECEIVER  
acknowledge  
SCL FROM  
MASTER  
1
8
9
S
clock pulse for  
acknowledgement  
I2C - bus.  
Voltage ””B‘‘  
START  
condition  
5 ms TYP  
Voltage ””A‘‘  
V
_APPS  
CC  
Figure 23. I2C DVM Timing for VCC_APPS (Buck1)  
20  
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MULTI-BYTE I2C COMMAND SEQUENCE  
To correctly function with the Monahan’s Power Management I2C the LP3972’s I2C serial interface shall support  
Random register Multi-byte command sequencing: During a multi-byte write the Master sends the Start command  
followed by the Device address, which is sent only once, followed by the 8 Bit register address, then 8 bits of  
data. The I2C slave must then accept the next random register address followed by 8 bits of data and continue  
this process until the master sends a valid stop condition.  
A Typical Multi-byte random register transfer is outlined below:  
Device Address,  
Register A Address, Ach,  
Register A Data, Ach  
Register M Address, Ach,  
Register M Data, Ach  
Register X Address, Ach,  
Register X Data, Ach  
Register Z Address, Ach,  
Register Z Data, Ach, Stop  
Note: The PMIC is not required to see the I2C device address for each transaction. A, M, X, and Z are Random  
numbers.  
ack from slave  
ack from slave  
ack from slave  
ack from slave  
ack from slave  
start  
msb Chip Address lsb  
w
ack  
msb Register Add lsb  
ack  
msb  
DATA  
lsb  
ack  
msb Register Add lsb  
ack  
msb  
DATA  
lsb  
ack stop  
Register 0x24  
Register 0x2A  
Figure 24.  
INCREMENTAL REGISTER I2C COMMAND SEQUENCE  
The LP3972 supports address increment (burst mode). When you have defined register address n data bytes  
can be sent and register address is incremented after each data byte has been sent. Address incrimination may  
be required for non XScale applications. User can define whether multi-byte (default) to random address or  
address incrimination will be used.  
ack from slave  
ack from slave  
ack from slave  
ack from slave  
ack from slave  
start  
msb Chip Address lsb  
w
ack  
msb Register Add lsb  
ack  
msb  
DATA1  
lsb  
ack  
msb  
DATA2  
lsb  
ack  
msb  
DATA3  
lsb  
ack stop  
Register 0x24  
Data (reg_0x24)  
Data (reg_0x25)  
Data (reg_0x26)  
Figure 25.  
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LP3972 CONTROL REGISTER  
Register Address  
8h’07  
Register Name  
Read/Write  
Register Description  
SCR  
R/W  
R/W  
R
System Control Register  
8h’10  
OVER1  
OVSR1  
OVER2  
OVSR2  
Output Voltage Enable Register 1  
Output Voltage Status Register 1  
Output Voltage Enable Register 2  
Output Voltage Status Register 2  
8h’11  
8h’12  
R/W  
R
8h’13  
8h’20  
VCC1  
R/W  
Voltage Change Control Register  
1
8h’23  
8h’24  
ADTV1  
ADTV2  
R/W  
R/W  
Buck1 Target Voltage 1 Register  
Buck1 DVM Target Voltage 2  
Register  
8h’25  
AVRC  
R/W  
VCC_APPS Voltage Ramp  
Control  
8h’26  
8h’27  
8h’29  
8h’2A  
8h’32  
8h’33  
8h’39  
8h’3A  
CDTC1  
CDTC2  
SDTV1  
SDTV2  
MDTV1  
MDTV2  
L2VCR  
L34VCR  
W
Dummy Register  
W
Dummy Register  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
LDO5 Target Voltage 1  
LDO5 Target Voltage 2  
LDO1 Target Voltage 1 Register  
LDO1 Voltage 2 Register  
LDO2 Voltage Control Registers  
LDO3 & LDO4 Voltage Control  
Registers  
8h’80  
8h’81  
8h’82  
8h’83  
8h’84  
8h’85  
8h’86  
8h’87  
8h’88  
8h’89  
SCR1  
SCR2  
OEN3  
OSR3  
LOER4  
B2TV  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R
System Control Register 1  
System Control Register 2  
Output Voltage Enable Register 3  
Output Voltage Status Register 3  
Output Voltage Enable Register 3  
VCC_Buck2 Target Voltage  
VCC_Buck3 Target Voltage  
Buck 3:2 Voltage Ramp Control  
Interrupt Status Register A  
B3TV  
B32RC  
ISRA  
BCCR  
R/W  
Backup Battery Charger Control  
Register  
8h’8E  
8h’8F  
II1RR  
II2RR  
R
R
Internal 1 Revision Register  
Internal 2 Revision Register  
SERIAL INTERFACE REGISTER SELECTION CODES (Bold face voltages are default values)  
System Control Status Register  
Register is an 8-bit register which specifies the control bits for the PMIC clocks. This register works in  
conjunction with the SYNC pin where an external clock PLL buffer operating at 13 MHz is synchronized with the  
oscillators of the buck converters.  
System Control Register (SCR) 8h’07  
Bit  
7
6
5
4
Reserved  
0
3
2
1
0
CLK_SCL  
0
Designation  
Reset Value  
0
0
0
0
0
0
22  
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System Control Register (SCR) 8h’07 Definitions  
Bit  
7-1  
0
Access  
Name  
Description  
Reserved  
R/W  
CLK_SCL  
External Clock Select  
0 = Internal Oscillator clock for Buck Converters  
1 = External 13 MHz Oscillator clock for Buck Converters  
OUTPUT VOLTAGE ENABLE REGISTER 1  
This register enables or disables the low voltage supplies LDO1 and Buck1. See details below.  
Output Voltage Enable Register 1 (OVER1) 8h’10  
Bit  
7
6
5
Reserved  
0
4
3
2
S_EN  
1
1
Reserved  
0
0
A_EN  
1
Designation  
Reset Value  
0
0
0
0
Output Voltage Enable Register 1 (OVER1) 8h’10 Definitions  
Bit  
Access  
Name  
Description  
7-3  
2
Reserved  
R/W  
S_EN  
VCC_SRAM (LDO5) Supply Output Enabled  
0 = VCC_SRAM (LDO5) Supply Output Disabled  
1 = VCC_SRAM (LDO5) Supply Output Enabled  
1
0
Reserved  
R/W  
A_EN  
VCC_APPS (Buck1) Supply Output Enabled  
0 = VCC_APPS (Buck1) Supply Output Disabled  
1 = VCC_APPS (Buck1) Supply Output Enabled  
OUTPUT VOLTAGE STATUS REGISTER  
This 8 bit register is used to indicate the status of the low voltage supplies. By polling each of the specify  
supplies is within its specified operating range.  
Output Voltage Status Register 1 (OVSR1) 8h’11  
Bit  
7
LP_OK  
0
6
5
4
3
2
S_OK  
0
1
Reserved  
0
0
A_OK  
0
Designation  
Reset Value  
Reserved  
0
0
0
0
Output Voltage Status Register 1 (OVSR1) 8h’11 Definitions  
Bit  
Access  
Name  
Description  
Low Voltage Supply Output Voltage Status  
7
R
LP_OK  
0 - VCC_APPS (Buck1) & VCC_SRAM (LDO5) output voltage < 90% of  
selected value  
1 - VCC_APPS (Buck1) & VCC_SRAM (LDO5) output voltage > 90% of  
selected value  
6:3  
2
R
Reserved  
S_OK  
VCC_SRAM Supply Output Voltage Status  
0 - VCC_SRAM (LDO5) output voltage < 90% of selected value  
1 - VCC_SRAM (LDO5) output voltage > 90% of selected value  
1
0
R
Reserved  
A_OK  
VCC_APPS Supply output Voltage Status  
0 - VCC_APPS (Buck1) output voltage < 90% of selected value  
1 - VCC_APPS (Buck1) output voltage > 90% of selected value  
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OUTPUT VOLTAGE ENABLE REGISTER 2  
This 8 bit output register enables and disables the output voltages on the LDOs 2,3,4 supplies.  
Output Voltage Enable Register 2 (OVER2) 8h’12  
Bit  
7
6
Reserved  
0
5
4(1)  
LDO4_EN  
0
3(1)  
LDO3_EN  
0
2(1)  
LDO2_EN  
0
1
0
Designation  
Reset Value  
Reserved  
0
0
0
0
(1) One-time factory programmable EPROM registers for default values  
Output Voltage Enable Register 2 (OVER2) 8h’12 Definitions  
Bit  
7
Access  
Name  
Description  
Reserved  
Reserved  
Reserved  
6
5
4
R/W  
LDO4_EN  
LDO4 Output Voltage Enable  
0 = LDO4 Supply Output Disabled, Default  
1 = LDO4 Supply Output Enabled  
3
2
R/W  
R/W  
LDO3_EN  
LDO2_EN  
LDO3 Output Voltage Enable  
0 = LDO3 Supply Output Disabled, Default  
1 = LDO3 Supply Output Enabled  
LDO2 Output Voltage Enable  
0 = LDO2 Supply Output Disabled, Default  
1 = LDO2 Supply Output Enabled  
1
0
Reserved  
Reserved  
OUTPUT VOLTAGE STATUS REGISTER 2  
Output Voltage Status Register 2 (OVSR2) 8h’13  
Bit  
7
LDO_OK  
0
6
N/A  
0
5
N/A  
0
4
LDO4_OK  
0
3
LDO3_OK  
0
2
LDO2_OK  
0
1
N/A  
0
0
N/A  
0
Designation  
Reset Value  
Output Voltage Status Register 2 (OVSR2) 8h’13 Definitions  
Bit  
Access  
Name  
Description  
7
R
LDO_OK  
LDOs 2-4 Supply Output Voltage Status  
0 - (LDOs 2-4) output voltage < 90% of selected value  
1 - (LDOs 2-4) output voltage > 90% of selected value  
6
5
4
R
Reserved  
Reserved  
LDO4_OK  
LDO4 Output Voltage Status  
0 - (VCC_LDO4) output voltage < 90% of selected value  
1 - (VCC_LDO4) output voltage > 90% of selected value  
3
2
R
R
LDO3_OK  
LDO2_OK  
LDO3 Output Voltage Status  
0 - (VCC_LDO3) output voltage < 90% of selected value  
1 - (VCC_LDO3) output voltage > 90% of selected value  
LDO2 Output Voltage Status  
0 - (VCC_LDO2) output voltage < 90% of selected value  
1 - (VCC_LDO2) output voltage > 90% of selected value  
1
0
Reserved  
Reserved  
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DVM VOLTAGE CHANGE CONTROL REGISTER 1  
DVM Voltage Change Control Register 1 (VCC1) 8h’20  
Bit  
7
MVS  
0
6
MGO  
0
5
SVS  
0
4
SGO  
0
3
2
1
AVS  
0
0
AGO  
0
Designation  
Reset Value  
Reserved  
0
0
DVM Voltage Change Control Register 1 (VCC1) 8h’20 Definitions  
Bit  
Access  
Name  
Description  
VCC_MVT (LDO1) Voltage Select  
7
R/W  
MVS  
0 - Change VCC_MVT Output Voltage to MDVT1  
1 - Change VCC_MVT Output Voltage to MDVT2  
6
5
4
R/W  
R/W  
R/W  
MGO  
SVS  
Start VCC_MVT (LDO1) Voltage Change  
0 - Hold VCC_MVT Output Voltage at current Level  
1 - Ramp VCC_MVT Output Voltage as selected by MVS  
VCC_SRAM (LDO5) Voltage Select  
0 - Change VCC_SRAM Output Voltage to SDTV1  
1 - Change VCC_SRAM Output Voltage to SDTV2  
SGO  
Start VCC_SRAM (LDO5) Voltage Change  
0 - Hold VCC_SRAM Output Voltage at current Level  
1 - Change VCC_SRAM Output Voltage as selected by SVS  
3:2  
1
Reserved  
R/W  
AVS  
VCC_APPS (Buck1) Voltage Select  
0 - Ramp VCC_APPS Output Voltage to ADVT1  
1 - Ramp VCC_APPS Output Voltage to ADVT2  
0
R/W  
AGO  
Start VCC_APPS(Buck1) Voltage Change  
0 - Hold VCC_APPS Output Voltage at current Level  
1 - Ramp VCC_APPS Output Voltage as selected by AVS  
BUCK1 (VCC_APPS) VOLTAGE 1  
Buck1 (VCC_APPS) Target Voltage 1 Register (ADTV1) 8h’23  
Bit  
7
6
Reserved  
0
5
4(1)  
3(1)  
2(1)  
1(1)  
0(1)  
Designation  
Reset Value  
Buck1 Output Voltage (B1OV1)  
0
0
0
1
0
1
1
(1) One-time factory programmable  
Buck1 (VCC_APPS) Target Voltage 1 Register (ADTV1) 8h’23 Definitions  
Bit  
7:5  
4:0  
Access  
Name  
Description  
Reserved  
R/W  
B1OV1  
Data Code  
5h’0  
Output Voltage  
Data Code  
5h’10  
5h’11  
5h’12  
5h’13  
5h’14  
5h’15  
5h’16  
5h’17  
5h’18  
5h’19  
5h’1A  
5h’1B  
5h’1C  
5h’1D  
5h’1E  
5h’1F  
Output Voltage  
1.125  
0.725  
0.750  
0.775  
0.800  
0.825  
0.850  
0.875  
0.900  
0.925  
0.950  
0.975  
1.000  
1.025  
1.050  
1.075  
1.100  
5h’1  
5h’2  
5h’3  
5h’4  
5h’5  
5h’6  
5h’7  
5h’8  
1.150  
1.175  
1.200  
1.225  
1.250  
1.275  
1.300  
1.325  
1.350  
1.375  
1.400  
1.425  
1.450  
1.475  
1.500  
5h’9  
5h’A  
5h’B  
5h’C  
5h’D  
5h’E  
5h’F  
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BUCK1 (VCC_APPS) TARGET VOLTAGE 2 REGISTER  
Buck1 (VCC_APPS) Target Voltage 2 Register (ADTV2) 8h’24  
Bit  
7
6
Reserved  
0
5
4
3
2
1
0
Designation  
Reset Value  
Buck1 Output Voltage (B1OV2)  
0
0
0
1
0
1
1
Buck1 (VCC_APPS) Target Voltage 2 Register (ADTV2) 8h’24 Definitions  
Bit  
7:5  
4:0  
Access  
Name  
Description  
Reserved  
Data Code  
R/W  
B1OV2  
Output Voltage  
Data Code  
5h’10  
5h’11  
5h’12  
5h’13  
5h’14  
5h’15  
5h’16  
5h’17  
5h’18  
5h’19  
5h’1A  
5h’1B  
5h’1C  
5h’1D  
5h’1E  
5h’1F  
Output Voltage  
1.125  
5h’0  
5h’1  
5h’2  
5h’3  
5h’4  
5h’5  
5h’6  
5h’7  
5h’8  
5h’9  
5h’A  
5h’B  
5h’C  
5h’D  
5h’E  
5h’F  
0.725  
0.750  
0.775  
0.800  
0.825  
0.850  
0.875  
0.900  
0.925  
0.950  
0.975  
1.000  
1.025  
1.050  
1.075  
1.100  
1.150  
1.175  
1.200  
1.225  
1.250  
1.275  
1.300  
1.325  
1.350  
1.375  
1.400  
1.425  
1.450  
1.475  
1.500  
BUCK1 (VCC_APPS) VOLTAGE RAMP CONTROL REGISTER  
Buck1 (VCC_APPS) Voltage Ramp Control Register (AVRC) 8h’25  
Bit  
7
6
Reserved  
0
5
4
3
2
1
0
Designation  
Reset Value  
Ramp Rate (B1RR)  
0
0
0
0
1
1
0
Buck1 (VCC_APPS) Voltage Ramp Control Register (AVRC) 8h’25 Definitions  
Bit  
Access  
Name  
Description  
7:5  
Reserved  
DVM Ramp Speed  
Data Code  
Ramp Rate (mV/uS)  
5h’0  
5h’1  
Instant  
1
5h’2  
2
5h’3  
3
5h’4  
5h’5  
4
5
4:0  
R/W  
B1RR  
5h’6  
6
5h’7  
7
5h’8  
8
5h’9  
5h’A  
4h’B-4h’1F  
9
10  
Reserved  
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VCC_COMM TARGET VOLTAGE 1 DUMMY REGISTER (CDTV1)  
VCC_COMM Target Voltage 1 Dummy Register (CDTV1) 8h’26 Write Only(1)  
Bit  
7
6
Reserved  
0
5
4
3
2
1
0
Designation  
Reset Value  
Output Voltage  
0
0
0
0
0
0
0
(1) CDTV1 must be writable by an I2C controller. This is a dummy register  
VCC_COMM TARGET VOLTAGE 2 DUMMY REGISTER (CDTV2)  
VCC_COMM Target Voltage 2 Dummy Register (CDTV2) 8h’27 Write Only(1)  
Bit  
7
6
Reserved  
0
5
4
3
2
1
0
Designation  
Reset Value  
Output Voltage  
0
0
0
0
0
0
0
(1) CDTV2 must be writable by an I2C controller. This is a dummy register and cannot be read.  
This is a variable voltage supply to the internal SRAM of the Application processor.  
LDO5 (VCC_SRAM) TARGET VOLTAGE 1 REGISTER  
LDO5 (VCC_SRAM) Target Voltage 1 Register (SDTV1) 8H'29  
Bit  
7
6
Reserved  
0
5
4(1)  
3(1)  
2(1)  
1*(1)  
0(1)  
Designation  
Reset Value  
LDO 5 Output Voltage (L5OV)  
0
0
0
0
1
1
1
(1) One-time factory programmable EPROM registers for default values  
LDO5 (VCC_SRAM) Target Voltage 1 Register (SDTV1) 8h’29 Definitions  
Bit  
7:5  
4:0  
Access  
Name  
Description  
Reserved  
Data Code  
R/W  
B1OV  
Output Voltage  
Data Code  
5h’10  
5h’11  
5h’12  
5h’13  
5h’14  
5h’15  
5h’16  
5h’17  
5h’18  
5h’19  
5h’1A  
5h’1B  
5h’1C  
5h’1D  
5h’1E  
5h’1F  
Output Voltage  
1.125  
5h’0  
5h’1  
5h’2  
5h’3  
5h’4  
5h’5  
5h’6  
5h’7  
5h’8  
5h’9  
5h’A  
5h’B  
5h’C  
5h’D  
5h’E  
5h’F  
1.150  
1.175  
1.200  
1.225  
1.250  
1.275  
1.300  
1.325  
1.350  
1.375  
1.400  
1.425  
1.450  
1.475  
1.500  
0.850  
0.875  
0.900  
0.925  
0.950  
0.975  
1.000  
1.025  
1.050  
1.075  
1.100  
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LDO5 (VCC_SRAM) TARGET VOLTAGE 2 REGISTER  
LDO5 (VCC_SRAM) Target Voltage 2 Register (SDTV2) 8h’2A  
Bit  
7
6
Reserved  
0
5
4
3
2
1
0
Designation  
Reset Value  
LDO 5 Output Voltage (L5OV)  
0
0
0
0
1
1
1
LDO5 (VCC_SRAM) Target Voltage 2 Register (SDTV2) 8h’2A Definitions  
Bit  
7:5  
4:0  
Access  
Name  
Description  
Reserved  
Data Code  
R/W  
B1OV  
Output Voltage  
Data Code  
5h’10  
5h’11  
5h’12  
5h’13  
5h’14  
5h’15  
5h’16  
5h’17  
5h’18  
5h’19  
5h’1A  
5h’1B  
5h’1C  
5h’1D  
5h’1E  
5h’1F  
Output Voltage  
1.125  
5h’0  
5h’1  
5h’2  
5h’3  
5h’4  
5h’5  
5h’6  
5h’7  
5h’8  
5h’9  
5h’A  
5h’B  
5h’C  
5h’D  
5h’E  
5h’F  
1.150  
1.175  
1.200  
1.225  
1.250  
1.275  
1.300  
1.325  
1.350  
1.375  
1.400  
1.425  
1.450  
1.475  
1.500  
0.850  
0.875  
0.900  
0.925  
0.950  
0.975  
1.000  
1.025  
1.050  
1.075  
1.100  
VCC_MVT is low tolerance regulated power supply for the application processor ring oscillator and logic for  
communicating to the LP3972. VCC_MVT is enabled when SYS_EN is asserted and disabled when SYS_EN is  
deasserted.  
LDO1 (VCC_MVT) TARGET VOLTAGE 1 REGISTER (MDTV1)  
LDO1 (VCC_MVT) Target Voltage 1 Register (MDTV1) 8h’32  
Bit  
7
6
Reserved  
0
5
4(1)  
3(1)  
2(1)  
1(1)  
0(1)  
Designation  
Reset Value  
Output Voltage (OV)  
1
0
0
0
0
0
0
(1) One-time factory programmable EPROM registers for default values  
LDO1 (VCC_MVT) Target Voltage 1 Register (MDTV1) 8h’32 Definitions  
Bit  
7:5  
4:0  
Access  
Name  
Description  
Reserved  
Data Code  
R/W  
L1OV  
Output Voltage  
1.700  
Notes:  
5h’0  
5h’1  
1.725  
5h’2  
1.750  
5h’3  
1.775  
5h’4  
5h’5  
1.800  
1.825  
5h’6  
1.850  
5h’7  
1.875  
5h’8  
1.900  
5h’9  
1.925  
5h’A  
5h’B  
5h’C  
5h’D-5h’F  
1.950  
1.975  
2.000  
Reserved  
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LDO1 (VCC_MVT) TARGET VOLTAGE 2 REGISTER  
LDO1 (VCC_MVT) Target Voltage 2 Register (MDTV2) 8h’33  
Bit  
7
6
Reserved  
0
5
4
3
2
1
0
Designation  
Reset Value  
Output Voltage (OV)  
0
0
0
0
1
1
1
LDO1 (VCC_MVT) Target Voltage 2 Register (MDTV2) 8h’33 Definitions  
Bit  
7:5  
4:0  
Access  
Name  
Description  
Reserved  
Data Code  
R/W  
L1OV  
Output Voltage  
1.700  
Notes:  
5h’0  
5h’1  
1.725  
5h’2  
1.750  
5h’3  
1.775  
5h’4  
5h’5  
1.800  
1.825  
5h’6  
1.850  
5h’7  
1.875  
5h’8  
1.900  
5h’9  
1.925  
5h’A  
5h’B  
5h’C  
5h’D-5h’F  
1.950  
1.975  
2.000  
Reserved  
LDO2 VOLTAGE CONTROL REGISTER (L12VCR)  
LDO2 Voltage Control Register (L12VCR) 8h’39  
Bit  
7(1)  
6(1)  
5(1)  
4(1)  
3
2
1
0
Designation  
Reset Value  
LDO2 Output Voltage (L2OV)  
Reserved  
0
0
0
0
0
0
0
0
(1) One-time factory programmable EPROM registers for default values  
LDO2 Voltage Control Register (L12VCR) 8h’39 Definitions  
Bit  
Access  
Name  
Description  
7:4  
R/W  
L2OV  
Data Code  
4h’0  
4h’1  
Output Voltage  
1.8 (Default)  
1.9  
4h’2  
2.0  
4h’3  
2.1  
4h’4  
2.2  
4h’5  
2.3  
4h’6  
2.4  
4h’7  
2.5  
4h’8  
2.6  
4h’9  
2.7  
4h’A  
4h’B  
4h’C  
4h’D  
4h’E  
4h’F  
2.8  
2.9  
3.0  
3.1  
3.2  
3.3  
3:0  
Reserved  
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LDO4 – LDO3 VOLTAGE CONTROL REGISTER (L34VCR)  
LDO4 – LDO3 Voltage Control Register (L34VCR) 8h’3A  
Bit  
7(1)  
6(1)  
5(1)  
4(1)  
3(1)  
2(1)  
1(1)  
0(1)  
Designation  
Reset Value  
LDO4 Output Voltage (L4OV)  
LDO3 Output Voltage (L3OV)  
0
0
0
0
0
0
0
0
(1) One-time factory programmable EPROM registers for default values  
LDO4 – LDO3 Voltage Control Register (L34VCR) 8h’3A Definitions  
Bit  
Access  
Name  
Description  
7:4  
R/W  
L4OV  
Data Code  
4h’0  
4h’1  
Output Voltage  
1.00  
1.05  
4h’2  
1.10  
4h’3  
1.15  
4h’4  
1.20  
4h’5  
1.25  
4h’6  
1.30  
4h’7  
1.35  
4h’8  
1.40  
4h’9  
1.50  
4h’A  
4h’B  
4h’C  
4h’D  
4h’E  
4h’F  
1.80  
1.90  
2.50  
2.80  
3.00 (Default)  
3.30  
3:0  
R/W  
L3OV  
Data Code  
4h’0  
Output Voltage  
1.8  
1.9  
4h’1  
4h’2  
2.0  
4h’3  
2.1  
4h’4  
2.2  
4h’5  
2.3  
4h’6  
2.4  
4h’7  
2.5  
4h’8  
2.6  
4h’9  
2.7  
4h’A  
4h’B  
4h’C  
4h’D  
4h’E  
4h’F  
2.8  
2.9  
3.0 (Default)  
3.1  
3.2  
3.3  
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TI DEFINED CONTROL AND STATUS REGISTERS  
SYSTEM CONTROL REGISTER 1 (SCR1)  
System Control Register 1 (SCR1) 8h’80  
Bit  
7(1)  
BPSEN  
0
6(1)  
5(1)  
4
FPWM3  
0
3
FPWM2  
0
2
FPWM1  
0
1
0
BK_SSEN  
0
Designation  
Reset Value  
SENDL  
BK_SLOMOD  
0
1
0
(1) One-time factory programmable EPROM registers for default values  
System Control Register 1 (SCR1) 8h’80 Definitions  
Bit  
Access  
Name  
Description  
7
R/W  
BPSEN  
Bypass System enable safety Lock. Prevents activation of PWR_EN  
when SYS_EN is low.  
0 = PWR_EN "AND" with SYS_EN signal, Default  
1 = PWR_EN independent of SYS_EN  
Delay time for High Voltage Power Domains LDO2, LDO3, LDO4,  
Buck2, and Buck3 after activation of SYS_EN. VCC_LDO1 has no  
delay.  
Data Code  
2h’0  
Delay (ms)  
6:5  
R/W  
SENDL  
0.0  
0.5  
2h’1  
2h’2  
2h’3  
1.0 (Default)  
1.4  
4
3
2
1
0
R/W  
R/W  
R/W  
R
FPWM3  
FPWM2  
Buck3 PWM/PFM Mode select  
0 - Auto Switch between PFM and PWM operation  
1 - PWM Mode Only will not switch to PFM  
Buck2 PWM/PFM Mode select  
0 - Auto Switch between PFM and PWM operation  
1 - PWM Mode Only will not switch to PFM  
FPWM1  
Buck1 PWM/PFM Mode select  
0 - Auto Switch between PFM and PWM operation  
1 - PWM Mode Only will not switch to PFM  
BK_SLOMOD  
BK_SSEN  
Buck Spread Spectrum Modulation Bucks 1-3  
0 = 10 kHz triangular wave spread spectrum modulation  
1 = 2 kHz triangular wave spread spectrum modulation  
R
Spread spectrum function Bucks 1-3  
0 = SS Output Disabled  
1 = SS Output Enabled  
SYSTEM CONTROL REGISTER 2 (SCR2)  
System Control Register 2 (SCR2) 8h’81  
Bit  
7
BBCS  
1
6
SHBU  
0
5(1)  
BPTR  
1
4
WUP3  
1
3
2
1
0
Designation  
GPIO2  
GPIO1  
0
0
1
0
(1) One time factory programmable EPROM registers for default values  
System Control Register 2 (SCR2) 8h’81 Definitions  
Bit  
Access  
Name  
Description  
7
R/W  
BBCS  
Sets GPIO1 as control input for Back Up battery charger  
0 - Back Up battery Charger GPIO Disabled  
1 - Back Up battery Charger GPIO Pin Enabled  
Shut down Back up battery to prevent battery drain during shipping  
0 = Back up Battery Enabled  
6
R/W  
SHBU  
1 = Back up battery Disabled  
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Bit  
Access  
Name  
Description  
5
R/W  
BPTR  
Bypass LDO_RTC Output Voltage to LDO3 Output Voltage Tracking  
0 - LDO_RTC3 Tracking enabled  
1 - LDO_RTC3 Tracking disabled, Default  
4
R/W  
R/W  
WUP3  
GPIO2  
Spare Wakeup control input  
0 - Active High  
1 - Active Low  
3:2  
Configure direction and output sense of GPIO2 Pin  
Data Code  
2h’00  
GPIO2  
Hi-Z  
2h’01  
2h’02  
Output Low  
Input  
2h’03  
Output high  
1:0  
R/W  
GPIO1  
Configure direction and output sense of GPIO1 Pin  
Data Code  
2h’00  
GPIO1  
Hi-Z  
2h’01  
2h’02  
Output Low  
Input  
2h’03  
Output high  
OUTPUT ENABLE 3 REGISTER (OEN3) 8H’82  
Bit  
7
6
Reserved  
0
5
4(1)  
B3EN  
1
3
2(1)  
B2EN  
1
1
Reserved  
0
0(1)  
L1EN  
1
Designation  
Reset Value  
ENFLAG  
0
0
0
(1) One time factory programmable EPROM registers for default values  
OUTPUT ENABLE 3 REGISTER (OEN3) 8H’82 DEFINITIONS  
Bit  
7:5  
4
Access  
Name  
Description  
Reserved  
R/W  
B3EN  
VCC_Buck3 Supply Output Enabled  
0 = VCC_Buck3 Supply Output Disabled  
1 = VCC_Buck3 Supply Output Enabled, Default  
3
2
R/W  
R/W  
ENFLAG  
B2EN  
Enable for Temperature Flags (BCT)  
0 = Temperature Flag Disabled  
1 = Temperature Flag Enabled  
VCC_Buck2 Supply Output Enabled  
0 = VCC_Buck2 Supply Output Disabled  
1 = VCC_Buck2 Supply Output Enabled, Default  
1
0
Reserved  
R/W  
L1EN  
LDO1 (MVT)Output Voltage Enable  
0 = LDO1 Supply Output Disabled  
1 = LDO1 Supply Output Enabled, Default  
STATUS REGISTER 3 (OSR3) 8H’83  
Bit  
7
BT_OK  
0
6
B3_OK  
0
5
B2_OK  
0
4
LDO1_OK  
0
3
Reserved  
0
2
BCT2  
0
1
BCT1  
0
0
BCT0  
0
Designation  
Reset Value  
STATUS REGISTER 3 (OSR3) DEFINITIONS 8H’83  
Bit  
Access  
Name  
Description  
7
R
BT_OK  
Bucks 2-3 Supply Output Voltage Status  
0 - (Bucks 1-3) output voltage < 90% Default value  
1 - (Bucsk 1-3) output voltage > 90% Default value  
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Bit  
Access  
Name  
Description  
6
R
B3_OK  
Buck3 Supply Output Voltage Status  
0 - (Buck3) output voltage < 90% Default value  
1 - (Buck3) output voltage > 90% Default value  
5
4
R
R
B2_OK  
Buck2 Supply Output Voltage Status  
0 - (Buck2) output voltage < 90% Default value  
1 - (Buck2) output voltage > 90% Default value  
LDO1_OK  
LDO1 Output Voltage Status  
0 - (VCC_LDO1) output voltage < 90% of selected value  
1 - (VCC_LDO1) output voltage > 90% of selected value  
3
R
Reserved  
2:0  
BCT  
Binary coded thermal management flag status register  
Temperature  
Data Code  
000  
Ascending °C  
40  
60  
001  
010  
80  
011  
100  
100  
120  
101  
140  
110  
160  
111  
Reserved  
LOGIC OUTPUT ENABLE REGISTER (LOER) 8H’84  
Bit  
7
Reserved  
0
6(1)  
B3ENC  
1
5(1)  
B2ENC  
1
4(1)  
3(1)  
L5EC  
0
2(1)  
1(1)  
L3EC  
1
0(1)  
L2EC  
1
Designation  
Reset Value  
B1ENC  
0
L4EC  
1
(1) One time factory programmable EPROM registers for default values  
LOGIC OUTPUT ENABLE REGISTER (LOER) DEFINITIONS 8H’84  
Bit  
7
Access  
Name  
Description  
Reserved  
6
R/W  
B3ENC  
Connects Buck3 enable to SYS_EN or PWR_EN Logic Control pin  
0 - Buck3 enable connected to PWR_EN  
1 - Buck3 enable connected to SYS_EN, Default  
5
4
3
2
1
0
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
B2ENC  
B1ENC  
L5EC  
Connects Buck2 enable to SYS_EN or PWR_EN Logic Control pin  
0 - Buck2 enable connected to PWR_EN  
1 - Buck2 enable connected to SYS_EN, Default  
Connects Buck1 enable to SYS_EN or PWR_EN Logic Control pin  
0 - Buck1 enable connected to PWR_EN, Default  
1 - Buck1 enable connected to SYS_EN  
Connects LDO5 enable to SYS_EN or PWR_EN Logic Control pin  
0 - LDO5 enable connected to PWR_EN, Default  
1 - LDO5 enable connected to SYS_EN  
L4EC  
Connects LDO4 enable to SYS_EN or PWR_EN Logic Control pin  
0 - LDO4 enable connected to PWR_EN  
1 - LDO4 enable connected to SYS_EN, Default  
L3EC  
Connects LDO3 enable to SYS_EN or PWR_EN Logic Control pin  
0 - LDO3 enable connected to PWR_EN  
1 - LDO3 enable connected to SYS_EN, Default  
L2EC  
Connects LDO2 enable to SYS_EN or PWR_EN Logic Control pin  
0 - LDO2 enable connected to PWR_EN  
1 - LDO2 enable connected to SYS_EN, Default  
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VCC_BUCK2 TARGET VOLTAGE REGISTER (B2TV) 8H’85  
Bit  
7
6
Reserved  
0
5
4(1)  
3(1)  
2(1)  
1(1)  
0(1)  
Designation  
Reset Value  
Buck2 Output Voltage (B2OV)  
0
0
0
1
1
0
1
(1) One time factory programmable EPROM registers for default values  
VCC_BUCK2 TARGET VOLTAGE REGISTER (B2TV) 8H’85 DEFINITIONS  
Bit  
7:5  
4:0  
Access  
Name  
Description  
Reserved  
R/W  
B2OV  
Output Voltage  
Data Code  
5h’01  
5h’02  
5h’03  
5h’04  
5h’05  
5h’06  
5h’07  
5h’08  
5h’09  
5h’0A  
5h’0B  
5h’0C  
(V)  
Data Code  
(V)  
0.80  
0.85  
0.90  
0.95  
1.00  
1.05  
1.10  
1.15  
1.20  
1.25  
1.30  
1.35  
5h’0D  
5h’0E  
5h’0F  
5h’10  
5h’11  
5h’12  
5h’13  
5h’14  
5h’15  
5h’16  
5h’17  
5h’18  
5h’19  
1.40  
1.45  
1.50  
1.55  
1.60  
1.65  
1.70  
1.80  
1.90  
2.50  
2.80  
3.00  
3.30  
BUCK3 TARGET VOLTAGE REGISTER (B3TV) 8H’86  
Bit  
7
6
Reserved  
0
5
4(1)  
3(1)  
2(1)  
1(1)  
0(1)  
Designation  
Reset Value  
Buck3 Output Voltage (B3OV)  
1
0
0
1
0
0
0
(1) One time factory programmable EPROM registers for default values  
BUCK3 TARGET VOLTAGE REGISTER (B3TV) 8H’86 DEFINITIONS  
Bit  
7:5  
4:0  
Access  
Name  
Description  
Reserved  
R/W  
B3OV  
Output Voltage  
Data Code  
5h’01  
5h’02  
5h’03  
5h’04  
5h’05  
5h’06  
5h’07  
5h’08  
5h’09  
5h’0A  
5h’0B  
5h’0C  
(V)  
Data Code  
5h’0D  
5h’0E  
5h’0F  
5h’11  
5h’12  
5h’13  
5h’14  
5h’15  
5h’16  
5h’17  
5h’18  
5h’19  
(V)  
0.80  
0.85  
0.90  
0.95  
1.00  
1.05  
1.10  
1.15  
1.20  
1.25  
1.30  
1.35  
1.40  
1.45  
1.50  
1.60  
1.65  
1.70  
1.80  
1.90  
2.50  
2.80  
3.00  
3.30  
Default  
VCC_BUCK3:2 VOLTAGE RAMP CONTROL REGISTER (B32RC)  
VCC_Buck3:2 Voltage Ramp Control Register (B32RC) 8h’87  
Bit  
7
6
5
4
3
2
1
0
Designation  
Ramp Rate (B3RR)  
Ramp Rate (B2RR)  
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Bit  
7
6
5
4
3
2
1
0
Reset Value  
1
0
1
0
1
0
1
0
Buck3:2 Voltage Ramp Control Register (B3RC) 8h’87 Definitions  
Bit  
Access  
Name  
Description  
7:4  
R/W  
B3RR  
Data Code  
4h’0  
Ramp Rate mV/µS  
Instant  
4h’1  
4h’2  
1
2
4h’3  
3
4h’4  
4
4h’5  
5
4h’6  
6
4h’7  
7
4h’8  
8
4h’9  
9
4h’A  
10  
3:0  
R/W  
B2RR  
Data Code  
4h’0  
Ramp Rate mV/µS  
Instant  
4h’1  
4h’2  
1
2
4h’3  
3
4h’4  
4
4h’5  
5
4h’6  
6
4h’7  
7
4h’8  
8
4h’9  
9
4h’A  
10  
INTERRUPT STATUS REGISTER ISRA  
This register specifies the status bits for the interrupts generated by the PMIC. Thermal warning of the IC,  
GPIO1, GPIO2, PWR_ON pin, TEST_JIG factory programmable on signal, and the SPARE pin.  
Interrupt Status Register ISRA 8h’88  
Bit  
7
Reserved  
0
6
T125  
0
5
GPI2  
0
4
GPI1  
0
3
WUP3  
0
2
WUP2  
0
1
WUPT  
0
0
WUPS  
0
Designation  
Reset Value  
Interrupt Status Register ISRA 8h’88 Definitions  
Bit  
7
Access  
Name  
Description  
R
Reserved  
6
T125  
Status bit for thermal warning PMIC T>125C  
0 = PMIC Temp. < 125°C  
1 = PMIC Temp. > 125°C  
5
4
3
2
R
R
R
R
GPI2  
GPI1  
Status bit for the input read in from GPIO 2 when set as Input  
0 = GPI2 Logic Low  
1 = GPI2 Logic High  
Status bit for the input read in from GPIO 1 when set as Input  
0 = GPI1 Logic Low  
1 = GPI1 Logic High  
WUP3  
WUP2  
PWR_ON Pin long pulse Wake Up Status  
0 = No wake up event  
1 = Long pulse wake up event  
PWR_ON Pin Short pulse Wake Up Status  
0 = No wake up event  
1 = Short pulse wake up event  
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Bit  
Access  
Name  
Description  
1
R
WUPT  
TEST_JIG Pin Wake Up Status  
0 = No wake up event  
1 = Wake up event  
0
R
WUPS  
SPARE Pin Wake Up Status  
0 = No wake up event  
1 = Wake up event  
BACKUP BATTERY CHARGER CONTROL REGISTER (BCCR)  
This register specifies the status of the main battery supply. NBUB bit  
Backup Battery Charger Control Register (BCCR) 8h’89  
Bit  
7(1)  
NBUB  
0
6
CNBFL  
0
5(1)  
4(1)  
nBFLT  
1
3(1)  
2
BUCEN  
0
1
0
Designation  
Reset Value  
IBUC  
0
0
0
1
(1) One time factory programmable EPROM registers for default values  
Backup Battery Charger Control Register (BCCR) 8h’89 Definitions  
Bit  
Access  
Name  
Description  
7
R/W  
NBUB  
No back-up battery default setting. Logic will not allow switch over to back-up  
battery.  
0 = Back up Battery Enabled, Default  
1 = Back up Battery Disabled  
6
R/W  
CNBFL  
Control for nBATT_FLT output signal  
0 = nBATT_FLT Enabled  
1 = nBATT_FLT Disabled  
nBATT_FLT monitors the battery voltage and can be set to the Assert voltages  
listed below.  
Data Code  
3h’01  
Asserted  
2.6  
De-Asserted  
2.8  
3.0 (Default)  
3.2  
5:3  
2
R/W  
R/W  
BFLT  
3h’02  
3h’03  
3h’04  
3h’05  
2.8  
3.0  
3.2  
3.4  
3.4  
3.6  
BUCEN  
Enables backup battery charger  
0 = Back up Battery Charger Disabled  
1 = Back up Battery Charger Enabled  
Charger current setting for back-up battery  
Data Code  
2h’00  
2h’01  
BU Charger I (µA)  
260  
190 (Default)  
325  
1:0  
R/W  
IBUC  
2h’02  
2h’03  
390  
MARVELL PXA INTERNAL 1 REVISION REGISTER (II1RR) 8H’8E  
Bit  
7
6
5
4
3
2
1
0
Designation  
Reset Value  
II1RR  
0
0
0
0
0
0
0
0
MARVELL PXA INTERNAL 1 REVISION REGISTER (II1RR) 8H’8E DEFINITIONS  
Bit  
Access  
Name  
Description  
7:0  
R
II1RR  
Intel internal usage register for revision information.  
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MARVELL PXA INTERNAL 2 REVISION REGISTER (II2RR) 8H’8F  
Bit  
7
6
5
4
3
2
1
0
Designation  
Reset Value  
II2RR  
0
0
0
0
0
0
0
0
MARVELL PXA INTERNAL 2 REVISION REGISTER (II2RR) 8H’8F DEFINITIONS  
Bit  
Access  
Name  
Description  
7:0  
R
II2RR  
Intel internal usage register for revision information.  
REGISTER PROGRAMMING EXAMPLES  
Example 1) Start of Day Sequence  
PMIC Register  
Address  
PMIC Register  
Name  
Register Data  
Description  
8h’23  
8h’29  
8h’10  
ADTVI  
SDTV1  
OVER1  
00011011  
00011011  
00000111  
Sets the SOD VCC_APPS voltage  
Sets the SOD VCC_SRAM voltage  
Enables VCC_SRAM and VCC_APPS to their programmed values.  
SODl Multi-byte random register transfer is outlined below:  
Device ID  
W
Ack  
Start  
0
1
1
0
1
1
0
0
0
1
1
0
0 0  
ADTV1 (8Z[23)  
Register Address  
Register Data (00011011)  
Data  
Ack  
Ack  
Ack  
Ack  
0
0
1
0
0
0
0 0 0 1 1 0 1 1  
SDTV1 (8Z[29)  
Register Address  
Register Data (00011011)  
Data  
Ack  
0
0
1
0
1
0
0 0 0 1 1 0 1 1  
OVER1 (8Z[10)  
Register Address  
Register Data (00000111)  
Data  
Ack Stop  
0
0
0
1
0
0
0 0 0 0 0 1 1 1  
Figure 26.  
Device Address,  
Register A Address, Ach,  
Register A Data, Ach  
Register M Address, Ach,  
Register M Data, Ach  
Register X Address, Ach,  
Register X Data, Ach  
Register Z Address, Ach,  
Register Z Data, Ach, Stop  
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Example 2) Voltage change Sequence  
PMIC Register  
Address  
PMIC Register  
Name  
Register Data  
Description  
8h’24  
8h’2A  
8h’20  
ADTV2  
SDTV2  
00010111  
00001111  
00110011  
Sets the VCC_APPS target voltage 2 to 1.3 V  
Sets the VCC_SRAM target voltage 2 to 1.1 V  
VCC1  
Enable VCC_SRAM and VCC_APPS to change to their programmed target  
values.  
I2C DATA EXCHANGE BETWEEN MASTER AND SLAVE DEVICE  
Device ID  
W
Ack  
Start  
0
1
1
0
1
0
1
0
0
0
0
0
0 0  
ADTV2 (8Z[24)  
Register Address  
Register Data (00010111)  
Data  
Ack  
Ack  
Ack  
Ack  
0
0
1
0
0
1
0 0 0 1 0 1 1 1  
SDTV2 (8Z[2A)  
Register Address  
Register Data (00001111)  
Data  
Ack  
0
0
1
0
1
0
0 0 0 0 1 1 1 1  
VCC1 (8Z[20)  
Register Address  
Register Data (00110011)  
Data  
Ack Stop  
0
0
1
0
0
0
0 0 1 1 0 0 1 1  
Figure 27.  
LP3972 Controls  
DIGITAL INTERFACE CONTROL SIGNALS  
Signal  
Definition  
Active State  
High  
Signal Direction  
Input  
SYS_EN  
PWR_EN  
SCL  
High Voltage Power Enable  
Low Voltage Power Enable  
Serial Bus Clock Line  
High  
Input  
Clock  
Input  
SDA  
Serial Bus Data Line  
Bidirectional  
Input  
nRSTI  
Forces an unconditional  
hardware reset  
Low  
Low  
Low  
nRSTO  
Forces an unconditional  
hardware reset  
Output  
Output  
nBATT_FLT  
Main Battery removed or  
discharged indicator  
PWR_ON  
nTEST_JIG  
SPARE  
Wakeup Input to CPU  
Wakeup Input to CPU  
Wakeup Input to CPU  
High  
Low  
Input  
Input  
High/Low  
High  
Input  
EXT_WAKEUP  
GPIO1 / nCHG_EN  
GPIO2  
Wake-Up Output for application  
processor  
Output  
General Purpose I/O /External  
Back-up Battery Charger enable  
Bidirectional /Input  
Bidirectional  
General Purpose I/O  
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POWER DOMAIN ENABLES  
PMU Output  
LDO_RTC  
HW Enable  
SW Enable  
LDO1 (VCC_MVT)  
LDO2  
SYS_EN  
SYS_EN  
SYS_EN  
SYS_EN  
PWR_EN  
PWR_EN  
SYS_EN  
SYS_EN  
LDO1_EN  
LDO2_EN  
LDO3_EN  
LDO4_EN  
S_EN  
LDO3  
LDO4  
LDO5 (VCC_SRAM)  
Buck1 (VCC_APPS)  
BUCK2  
A_EN  
B2_EN  
B3_EN  
BUCK3  
POWER DOMAINS SEQUENCING (DELAY)  
By default SYS_EN must be on to have PWR_EN enable but this feature can be switched off by register bit  
BP_SYS.  
By default SYS_EN enables LDO1 always first and after a typical of 1 ms delay others. Also when SYS_EN is  
set off the LDO1 will go off last. This function can be switched off or delay can be changed by DELAY bits via  
serial interface as seen on table below.  
8h’80 Bit 5:4  
DELAY bits  
Delay, ms  
‘00’  
0
‘01’  
0.5  
‘10’  
1.0  
‘11’  
1.5  
LDO_RTC TRACKING (nIO_TRACK)  
LP3972 has a tracking function (nIO_TRACK). When enabled, LDO_RTC voltage will track LDO3 voltage within  
200 mV down to 2.8V when LDO3 is enabled. This function can be switched on/off by nIO_TRACK register bit  
BPTR.  
POWER SUPPLY ENABLE  
SYS_EN and PWR_EN can be changed by programmable register bits.  
WAKE-UP FUNCTIONALITY (PWR_ON, nTEST_JIG, SPARE AND EXT_WAKEUP)  
Three input pins can be used to assert wakeup output for 10 ms for application processor notification to wakeup.  
SPARE Input can be programmed through I2C compatible interface to be active low or high (SPARE bit, Default  
is active low ‘1’). A reason for wakeup event can be read through I2C compatible interface also. Additionally  
wakeup inputs have 30 ms de-bounce filtering. Furthermore PWR_ON have distinguishing between short and  
long (1s) pulses (push button input). LP3972 also has an internal Thermal Shutdown early warning that  
generates a wakeup to the system also. This is generated usually at 125°C.  
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PWR_ON  
nTEST_JIG  
SPARE  
OR  
EXT_WAKEUP  
PWR_ON  
nTEST_JIG  
SPARE  
EXT_WAKEUP  
10 ms  
Internal Thermal Early Warning  
Figure 28.  
WAKEUP register bits  
WUP0  
Reason for WAKEUP  
SPARE  
WUP1  
TEST_JIG  
WUP2  
PWR_ON short pulse  
PWR_ON long pulse  
TSD Early Warning  
WUP3  
TSD_EW  
INTERNAL THERMAL SHUTDOWN PROCEDURE  
Thermal shutdown is build to generate early warning (typ. 125°C) which triggers the EXT_WAKEUP for the  
processor acknowledge. When a thermal shutdown triggers (typ. 160°C) the PMU will reset the system until the  
device cools down.  
BATTERY SWITCH AND BACK UP BATTERY CHARGER  
When Back-Up battery is connected but the main battery has been removed or its supply voltage too low,  
LP3972 uses Back-Up Battery for generating LDO_RTC voltage. When Main Battery is available the battery FET  
switches over to the main battery for LDO_RTC voltage. When Main battery voltage is too low or removed  
nBATT_FLT is asserted. If no back up battery exists, the battery switch to back up can be switched off by  
nBU_BAT_EN bit. User can set the battery fault determination voltage and battery charger current via I2C  
compatible interface. Enabling of back up battery charger can be done via serial interface (nBAT_CHG_EN) or  
external charger enable pin (nCHG_EN). Pin 29 is set as external charger enable input by default.  
GENERAL PURPOSE I/O FUNCTIONALITY (GPIO1 AND GPIO2)  
LP3972 has 2 general purpose I/Os for system control. I2C compatible interface will be used for setting any of the  
pins to input, output or hi-Z mode. Inputs value can be read via serial interface (GPIO1,2 bits). The pin 29  
functionality needs to be set to GPIO by serial interface register bit nEXTCHGEN. (GPIO/CHG)  
Controls  
Nextchgen_sel  
Port Function  
GPIO1  
Reg  
batmonchg  
Function  
GPIO<1>  
GPIO<1>  
bucen  
Gpin 1  
X
X
1
X
0
1
0
X
X
0
X
0
0
1
1
1
1
X
0
0
0
0
0
Input = 0  
Input = 1  
X
0
0
0
Enabled  
Not Enabled  
X
1
X
Enabled  
X
X
X
HiZ  
Input (dig)->  
Output = 0  
Input  
0
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Controls  
Nextchgen_sel  
Port Function  
GPIO1  
Reg  
Gpin 1  
0
batmonchg  
Function  
GPIO<1>  
GPIO<1>  
1
bucen  
X
1
0
Output = 1  
GPIO<1>  
GPIO<1>  
Factory fm disabled  
GPIO_tstiob  
GPIO2  
gpin2  
0
1
0
1
0
0
1
1
1
1
1
1
HiZ  
0
input  
0
Input (dig)->  
Output = 0  
Output = 1  
0
The LP3972 has provision for two battery connections, the main battery VBAT and Backup Battery (See  
Applications Schematic Diagrams 1 & 2 of the LP3972 Data Sheet).  
The function of the battery switch is to connect power to the LDO_RTC from the appropriate battery, depending  
on conditions described below:  
If only the backup battery is applied, the switch will automatically connect the LDO_RTC power to this battery.  
If only the main battery is applied, the switch will automatically connect the LDO_RTC power to this battery.  
If both batteries are applied, and the main battery is sufficiently charged (VBAT > 3.1V), the switch will  
automatically connect the RTC LDO power to the main battery.  
As the main battery is discharged by use, the user will be warned by a separate circuit called nBATT_FLT.  
Then if no action is taken to restore the charge on the main battery, and discharging is continued the battery  
switch will protect the LDO_RTC by disconnecting from the main battery and connecting to the backup  
battery.  
The main battery voltage at which the LDO_RTC is switched from main to backup battery is 2.9V typically.  
There is a hysteresis voltage in this switch operation so, the LDO_RTC will not be reconnected to main  
battery until main battery voltage is greater than 3.1V typically.  
Additionally, the user may wish to disable the battery switch, such as, in the case when only a main battery is  
used. This is accomplished by setting the "no back up battery bit" in the control register 8h’89 bit 7 NBUB.  
With this bit set to "1", the above described switching will not occur, that is the LDO_RTC will remain  
connected to the main battery even as it is discharged below the 2.9 Volt threshold.  
REGULATED VOLTAGES OK  
All the power domains have own register bit (X_OK) that processor can read via serial interface to be sure that  
enabled powers are OK (regulating). Note that these read only bits are only valid when regulators are settled  
(avoid reading these bits during voltage change or power up).  
THERMAL MANAGEMENT  
Application: There is a mode wherein all 6 comparators (flags) can be turned on via the "enallflags" control  
register bit. This mode allows the user to interrogate the device or system temperature under the set operating  
conditions. Thus, the rate of temperature change can also be estimated. The system may then negotiate for  
speed and power trade off, or deploy cooling maneuvers to optimize system performance. The "enallflags" bit  
needs enabled only when the "bct<2:0> bits are read to conserve power.  
Note: The thermal management flags have been verified functional. Presently these registers are accessible by  
factory only. If there is a demand for this function, the relevant register controls may be shifted into the user  
programmable bank; the temperature range and resolution of these flags, might also be refined/redefined.  
THERMAL WARNING  
2 of 6 low power comparators, each consumes less than 1 µA, are always enabled to operate the "T=125°C  
warning flag with hysteresis. This allows continuous monitoring of a thermal-warning flag feature with very low  
power consumption.  
LP3972 THERMAL FLAGS FUNCTIONAL DIAGRAM, DATA FROM INITIAL SILICON  
The following functions are extra features from the thermal shutdown circuit:  
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1) Thermal warning flag @ Temp ~ > ~125oC is issued at the wakeup port:  
~30oC hysteresis  
Temp 125oC  
Warning flag  
2) Binary coded thermal management flags in status registers, bct<2:0>:  
flag6  
flag5  
flag4  
flag3  
flag2  
flag1  
cool  
17oC 20oC 43oC 46oC 62oC 65oC 83oC 86oC 106oC108oC 128oC 130oC  
Temp  
Figure 29.  
Application Note - LP3972 Reset Sequence  
INITIAL COLD START POWER ON SEQUENCE  
1. The Back up battery is connected to the PMU, power is applied to the back-up battery pin, the LDO_RTC  
turns on and supplies a stable output voltage to the VCC_BATT pin of the Applications processor (initiating  
the power-on reset event) with nRSTO asserted from the LP3972 to the processor.  
2. nRSTO de-asserts after a minimum of 50 mS.  
3. The Applications processor waits for the de-assertion of nBATT_FLT to indicate system power (VIN) is  
available.  
4. After system power (VIN) is applied, the LP3972 de-asserts nBATT_FLT. Note that BOTH nRSTO and  
nBATT_FLT need to be de-asserted before SYS_EN is enabled. The sequence of the two signals is  
independent of each other.  
5. The Applications processor asserts SYS_EN, the LP3972 enables the system high-voltage power supplies.  
The Applications processor starts its countdown timer set to 125 mS.  
6. The LP3972 enables the high-voltage power supplies.  
LDO1 power for VCC_MVT (Power for internal logic and I/O Blocks), BG (Bandgap reference voltage),  
OSC13M (13 MHz oscillator voltage) and PLL enabled first, followed by others if delay is on.  
7. Countdown timer expires; the Applications processor asserts PWR_EN to enable the low-voltage power  
supplies. The processor starts the countdown timer set to 125 mS period.  
8. The Applications processor asserts PWR_EN (ext. pin or I2C), the LP3972 enables the low-voltage  
regulators.  
9. Countdown timer expires; If enabled power domains are OK (I2C read) the power up sequence continues by  
enabling the processors 13 MHz oscillator and PLL’s.  
10. The Applications processor begins the execution of code.  
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t
t
t
4
1
3
BU Batt  
V
IN  
1.  
VCC_RTC  
nRSTO  
2.  
V
Main Batt  
IN  
3,4.  
nBATT_FLT  
5.  
6.  
SYS_EN  
PXA27x Output  
High-Volt_PD  
PWR_EN  
7.  
PXA27x Output  
8.  
Low-Volt_PD  
t
2
t
5
nRESET_OUT  
13 MHZ_OSC  
PXA27x Output  
PXA27x Output  
9,10.  
* Note that BOTH nRSTO and nBATT_FLT need to be de-asserted before SYS_EN is enabled. The sequence of the  
two signals is independent of each other and can occur is either order.  
Figure 30.  
POWER-ON TIMING  
Symbol  
Description  
Min  
Typ  
Max  
Unit  
mS  
µS  
t1  
t2  
t3  
t4  
t5  
Delay from VCC_RTC assertion to nRSTO de-assertion  
Delay from nBATT_FLT de-assertion to nRSTI assertion  
Delay from nRST de-assertion to SYS_EN assertion  
Delay from SYS_EN assertion to PWR_EN assertion  
Delay from PWR_EN assertion to nRSTO de-assertion  
50  
100  
10  
mS  
mS  
mS  
125  
125  
HARDWARE RESET SEQUENCE  
Hardware reset initiates when the nRSTI signal is asserted (low). Upon assertion of nRST the processor enters  
hardware reset state. The LP3972 holds the nRST low long enough (50 ms typ.) to allow the processor time to  
initiate the reset state.  
RESET SEQUENCE  
1. nRSTI is asserted.  
2. nRSTO is asserted and will de-asserts after a minimum of 50 mS  
3. The Applications processor waits for the de-assertion of nBATT_FLT to indicate system power (VIN) is  
available.  
4. After system power (VIN) is turned on, the LP3972 de-asserts nBATT_FLT.  
5. The Applications processor asserts SYS_EN, the LP3972 enables the system high-voltage power supplies.  
The Applications processor starts its countdown timer.  
6. The LP3972 enables the high-voltage power supplies.  
7. Countdown timer expires; the Applications processor asserts PWR_EN to enable the low-voltage power  
supplies. The processor starts the countdown timer.  
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8. The Applications processor asserts PWR_EN, the LP3972 enables the low-voltage regulators.  
9. Countdown timer expires; If enabled power domains are OK (I2C read) the power up sequence continues by  
enabling the processors 13 MHz oscillator and PLL’s.  
10. The Applications processor begins the execution of code.  
APPLICATION HINTS  
LDO CONSIDERATIONS  
External Capacitors  
The LP3972’s regulators require external capacitors for regulator stability. These are specifically designed for  
portable applications requiring minimum board space and smallest components. These capacitors must be  
correctly selected for good performance.  
Input Capacitor  
An input capacitor is required for stability. It is recommended that a 1.0 µF capacitor be connected between the  
LDO input pin and ground (this capacitance value may be increased without limit).  
This capacitor must be located a distance of not more than 1 cm from the input pin and returned to a clean  
analogue ground. Any good quality ceramic, tantalum, or film capacitor may be used at the input.  
Important: Tantalum capacitors can suffer catastrophic failures due to surge current when connected to a low  
impedance source of power (like a battery or a very large capacitor). If a tantalum capacitor is used at the input,  
it must be ensured by the manufacturer to have a surge current rating sufficient for the application.  
There are no requirements for the ESR (Equivalent Series Resistance) on the input capacitor, but tolerance and  
temperature coefficient must be considered when selecting the capacitor to ensure the capacitance will remain  
approximately 1.0 µF over the entire operating temperature range.  
Output Capacitor  
The LDOs are designed specifically to work with very small ceramic output capacitors. A 1.0 µF ceramic  
capacitor (temperature types Z5U, Y5V or X7R) with ESR between 5 mto 500 m, are suitable in the  
application circuit.  
For this device the output capacitor should be connected between the VOUT pin and ground.  
It is also possible to use tantalum or film capacitors at the device output, COUT (or VOUT), but these are not as  
attractive for reasons of size and cost (see the section Capacitor Characteristics).  
The output capacitor must meet the requirement for the minimum value of capacitance and also have an ESR  
value that is within the range 5 mto 500 mfor stability.  
No-Load Stability  
The LDOs will remain stable and in regulation with no external load. This is an important consideration in some  
circuits, for example CMOS RAM keep-alive applications.  
Capacitor Characteristics  
The LDOs are designed to work with ceramic capacitors on the output to take advantage of the benefits they  
offer. For capacitance values in the range of 0.47 µF to 4.7 µF, ceramic capacitors are the smallest, least  
expensive and have the lowest ESR values, thus making them best for eliminating high frequency noise. The  
ESR of a typical 1.0 µF ceramic capacitor is in the range of 20 mto 40 m, which easily meets the ESR  
requirement for stability for the LDOs.  
For both input and output capacitors, careful interpretation of the capacitor specification is required to ensure  
correct device operation. The capacitor value can change greatly, depending on the operating conditions and  
capacitor type. In particular, the output capacitor selection should take account of all the capacitor parameters, to  
ensure that the specification is met within the application. The capacitance can vary with DC bias conditions as  
well as temperature and frequency of operation. Capacitor values will also show some decrease over time due to  
aging. The capacitor parameters are also dependant on the particular case size, with smaller sizes giving poorer  
44  
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performance figures in general. As an example, Figure 31 shows a typical graph comparing different capacitor  
case sizes in a Capacitance vs. DC Bias plot. As shown in the graph, increasing the DC Bias condition can result  
in the capacitance value falling below the minimum value given in the recommended capacitor specifications  
table. Note that the graph shows the capacitance out of spec for the 0402 case size capacitor at higher bias  
voltages. It is therefore recommended that the capacitor manufacturers’ specifications for the nominal value  
capacitor are consulted for all conditions, as some capacitor sizes (e.g. 0402) may not be suitable in the actual  
application.  
0603, 10V, X5M  
100%  
80%  
60%  
40%  
0402, 6.3V, X5R  
20%  
0
1.0  
2.0  
3.0  
4.0  
5.0  
DC BIAS (V)  
Figure 31. Graph Showing a Typical Variation in Capacitance vs. DC Bias  
The ceramic capacitor’s capacitance can vary with temperature. The capacitor type X7R, which operates over a  
temperature range of 55°C to +125°C, will only vary the capacitance to within ±15%. The capacitor type X5R  
has a similar tolerance over a reduced temperature range of 55°C to +85°C. Many large value ceramic  
capacitors, larger than 1 µF are manufactured with Z5U or Y5V temperature characteristics. Their capacitance  
can drop by more than 50% as the temperature varies from 25°C to 85°C. Therefore X7R is recommended over  
Z5U and Y5V in applications where the ambient temperature will change significantly above or below 25°C.  
Tantalum capacitors are less desirable than ceramic for use as output capacitors because they are more  
expensive when comparing equivalent capacitance and voltage ratings in the 0.47 µF to 4.7 µF range.  
Another important consideration is that tantalum capacitors have higher ESR values than equivalent size  
ceramics. This means that while it may be possible to find a tantalum capacitor with an ESR value within the  
stable range, it would have to be larger in capacitance (which means bigger and more costly) than a ceramic  
capacitor with the same ESR value. It should also be noted that the ESR of a typical tantalum will increase about  
2:1 as the temperature goes from 25°C down to –40°C, so some guard band must be allowed.  
BUCK CONSIDERATIONS  
Inductor Selection  
There are two main considerations when choosing an inductor; the inductor should not saturate, and the inductor  
current ripple is small enough to achieve the desired output voltage ripple. Different saturation current rating  
specs are followed by different manufacturers so attention must be given to details. Saturation current ratings are  
typically specified at 25°C so ratings at max ambient temperature of application should be requested from  
manufacturer.  
There are two methods to choose the inductor saturation current rating.  
Method 1  
The saturation current is greater than the sum of the maximum load current and the worst case average to peak  
inductor current. This can be written as  
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ISAT > IOUTMAX + IRIPPLE  
«
*
«
«
«
«
«
VIN - VOUT  
VOUT  
VIN  
1
f
where IRIPPLE  
=
*
L
2
*
where  
IRIPPLE: Average to peak inductor current  
IOUTMAX: Maximum load current (1500 mA)  
VIN: Maximum input voltage in application  
L: Min inductor value including worst case tolerances (30% drop can be considered for method 1)  
f: Minimum switching frequency (1.6 MHz)  
VOUT: Output voltage  
(2)  
Method 2  
A more conservative and recommended approach is to choose an inductor that has saturation current rating  
greater than the max current limit of 3A.  
A 2.2 µH inductor with a saturation current rating of at least 3A is recommended for most applications. The  
inductor’s resistance should be less than 0.3for a good efficiency. Table 1 lists suggested inductors and  
suppliers. For low-cost applications, an unshielded bobbin inductor could be considered. For noise critical  
applications, a toroidal or shielded bobbin inductor should be used. A good practice is to lay out the board with  
overlapping footprints of both types for design flexibility. This allows substitution of a low-noise shielded inductor,  
in the event that noise from low-cost bobbin models is unacceptable.  
Input Capacitor Selection  
A ceramic input capacitor of 10 µF, 6.3V is sufficient for most applications. Place the input capacitor as close as  
possible to the VIN pin of the device. A larger value may be used for improved input voltage filtering. Use X7R or  
X5R types, do not use Y5V. DC bias characteristics of ceramic capacitors must be considered when selecting  
case sizes like 0805 and 0603. The input filter capacitor supplies current to the PFET switch of the converter in  
the first half of each cycle and reduces voltage ripple imposed on the input power source. A ceramic capacitor’s  
low ESR provides the best noise filtering of the input voltage spikes due to this rapidly changing current. Select a  
capacitor with sufficient ripple current rating. The input current ripple can be calculated as:  
«
r2  
VOUT  
VIN  
VOUT  
VIN  
*
IRMS = IOUTMAX  
1 -  
+
*
12  
«
VOUT  
(VIN - VOUT  
)
*
where r =  
VIN  
L
f
IOUTMAX  
*
*
*
(3)  
The worst case is when VIN = 2 * VOUT  
Table 1. Suggested Inductors and Their Suppliers  
Model  
Vendor  
Toko  
Dimensions LxWxH (mm)  
3.0 x 3.0 x 1.2  
D.C.R. (Typ)  
FDSE0312-2R2M  
DO1608C-222  
160 mΩ  
80 mΩ  
Coilcraft  
6.6 x 4.5 x 1.8  
Output Capacitor Selection  
Use a 10 µF, 6.3V ceramic capacitor. Use X7R or X5R types, do not use Y5V. DC bias characteristics of ceramic  
capacitors must be considered when selecting case sizes like 0805 and 0603. DC bias characteristics vary from  
manufacturer to manufacturer and dc bias curves should be requested from them as part of the capacitor  
selection process. The output filter capacitor smooths out current flow from the inductor to the load, helps  
maintain a steady output voltage during transient load changes and reduces output voltage ripple. These  
capacitors must be selected with sufficient capacitance and sufficiently low ESR to perform these functions.  
46  
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The output voltage ripple is caused by the charging and discharging of the output capacitor and also due to its  
ESR and can be calculated as:  
IRIPPLE  
VPP-C  
=
4
f C  
* *  
(4)  
(5)  
Voltage peak-to-peak ripple due to ESR can be expressed as follows  
VPP-ESR = (2 * IRIPPLE) * RESR  
Because these two components are out of phase the RMS value can be used to get an approximate value of  
peak-to-peak ripple.  
Voltage peak-to-peak ripple, root mean squared can be expressed as follows  
2
VPP-C2 + VPP-ESR  
VPP-RMS  
=
(6)  
Note that the output voltage ripple is dependent on the inductor current ripple and the equivalent series  
resistance of the output capacitor (RESR).  
The RESR is frequency dependent (as well as temperature dependent); make sure the value used for calculations  
is at the switching frequency of the part.  
Table 2. Suggested Capacitor and Their Suppliers  
Model  
GRM21BR60J106K  
JMK212BJ106K  
Type  
Ceramic, X5R  
Vendor  
Murata  
Voltage  
6.3V  
Case Size Inch (mm)  
0805 (2012)  
Ceramic, X5R  
Ceramic, X5R  
Taiyo-Yuden  
TDK  
6.3V  
0805 (2012)  
C2012X5R0J106K  
6.3V  
0805 (2012)  
Buck Output Ripple Management  
If VIN and ILOAD increase, the output ripple associated with the Buck Regulators also increases. Figure 32 shows  
the safe operating area. To ensure operation in the area of concern it is recommended that the system designer  
circumvents the output ripple issues to install Schottky diodes on the Buck(s) that are expected to perform under  
these extreme corner conditions.  
(Schottky diodes are recommended to reduce the output ripple, if system requirements include this shaded area  
of operation. VIN > 1.5V and ILOAD > 1.24)  
5.5  
5.0  
4.5  
4.0  
3.5  
3.0  
0
0.5  
1.0  
1.5  
LOAD CURRENT (A)  
Figure 32.  
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Board Layout Considerations  
PC board layout is an important part of DC-DC converter design. Poor board layout can disrupt the performance  
of a DC-DC converter and surrounding circuitry by contributing to EMI, ground bounce, and resistive voltage loss  
in the traces. These can send erroneous signals to the DC-DC converter IC, resulting in poor regulation or  
instability.  
Good layout for the converters can be implemented by following a few simple design rules.  
1. Place the converters, inductor and filter capacitors close together and make the traces short. The traces  
between these components carry relatively high switching currents and act as antennas. Following this rule  
reduces radiated noise. Special care must be given to place the input filter capacitor very close to the VIN  
and GND pin.  
2. Arrange the components so that the switching current loops curl in the same direction. During the first half of  
each cycle, current flows from the input filter capacitor through the converter and inductor to the output filter  
capacitor and back through ground, forming a current loop. In the second half of each cycle, current is pulled  
up from ground through the converter by the inductor to the output filter capacitor and then back through  
ground forming a second current loop. Routing these loops so the current curls in the same direction  
prevents magnetic field reversal between the two half-cycles and reduces radiated noise.  
3. Connect the ground pins of the converter and filter capacitors together using generous component-side  
copper fill as a pseudo-ground plane. Then, connect this to the ground-plane (if one is used) with several  
vias. This reduces ground-plane noise by preventing the switching currents from circulating through the  
ground plane. It also reduces ground bounce at the converter by giving it a low-impedance ground  
connection.  
4. Use wide traces between the power components and for power connections to the DC-DC converter circuit.  
This reduces voltage errors caused by resistive losses across the traces.  
5. Route noise sensitive traces, such as the voltage feedback path, away from noisy traces between the power  
components. The voltage feedback trace must remain close to the converter circuit and should be direct but  
should be routed opposite to noisy components. This reduces EMI radiated onto the DC-DC converter’s own  
voltage feedback trace. A good approach is to route the feedback trace on another layer and to have a  
ground plane between the top layer and layer on which the feedback trace is routed. In the same manner for  
the adjustable part it is desired to have the feedback dividers on the bottom layer.  
6. Place noise sensitive circuitry, such as radio RF blocks, away from the DC-DC converter, CMOS digital  
blocks and other noisy circuitry. Interference with noise-sensitive circuitry in the system can be reduced  
through distance.  
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REVISION HISTORY  
Changes from Revision J (May 2013) to Revision K  
Page  
Changed layout of National Data Sheet to TI format .......................................................................................................... 48  
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PACKAGE OPTION ADDENDUM  
www.ti.com  
7-Oct-2013  
PACKAGING INFORMATION  
Orderable Device  
LP3972SQ-0514/NOPB  
LP3972SQ-5810/NOPB  
LP3972SQ-A413/NOPB  
Status Package Type Package Pins Package  
Eco Plan Lead/Ball Finish  
MSL Peak Temp  
Op Temp (°C)  
Device Marking  
Samples  
Drawing  
Qty  
(1)  
(2)  
(3)  
(4/5)  
ACTIVE  
WQFN  
WQFN  
WQFN  
RSB  
40  
40  
40  
1000  
Green (RoHS  
& no Sb/Br)  
CU SN  
CU SN  
CU SN  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
72-0514  
ACTIVE  
ACTIVE  
RSB  
RSB  
1000  
1000  
Green (RoHS  
& no Sb/Br)  
72-5810  
72-A413  
Green (RoHS  
& no Sb/Br)  
-40 to 125  
LP3972SQ-A514  
ACTIVE  
ACTIVE  
WQFN  
WQFN  
RSB  
RSB  
40  
40  
1000  
1000  
TBD  
Call TI  
CU SN  
Call TI  
-40 to 125  
-40 to 125  
72-A514  
72-A514  
LP3972SQ-A514/NOPB  
Green (RoHS  
& no Sb/Br)  
Level-1-260C-UNLIM  
LP3972SQ-E514/NOPB  
LP3972SQ-I414/NOPB  
ACTIVE  
ACTIVE  
WQFN  
WQFN  
RSB  
RSB  
40  
40  
1000  
1000  
Green (RoHS  
& no Sb/Br)  
CU SN  
CU SN  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
-40 to 125  
-40 to 125  
72-E514  
72-I414  
Green (RoHS  
& no Sb/Br)  
LP3972SQ-I514  
ACTIVE  
ACTIVE  
WQFN  
WQFN  
RSB  
RSB  
40  
40  
1000  
1000  
TBD  
Call TI  
CU SN  
Call TI  
-40 to 125  
-40 to 125  
72-I514  
72-I514  
LP3972SQ-I514/NOPB  
Green (RoHS  
& no Sb/Br)  
Level-1-260C-UNLIM  
LP3972SQE-A413/NOPB  
ACTIVE  
WQFN  
RSB  
40  
250  
Green (RoHS  
& no Sb/Br)  
CU SN  
Level-1-260C-UNLIM  
72-A413  
LP3972SQE-A514  
OBSOLETE  
ACTIVE  
WQFN  
WQFN  
RSB  
RSB  
40  
40  
TBD  
TBD  
Call TI  
Call TI  
Call TI  
Call TI  
LP3972SQE-A514/NOPB  
250  
250  
LP3972SQE-E514/NOPB  
LP3972SQE-I514/NOPB  
LP3972SQX-0514/NOPB  
LP3972SQX-5810/NOPB  
LP3972SQX-A413/NOPB  
LP3972SQX-A514/NOPB  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
WQFN  
WQFN  
WQFN  
WQFN  
WQFN  
WQFN  
RSB  
RSB  
RSB  
RSB  
RSB  
RSB  
40  
40  
40  
40  
40  
40  
Green (RoHS  
& no Sb/Br)  
CU SN  
CU SN  
CU SN  
CU SN  
CU SN  
CU SN  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
72-E514  
72-I514  
72-0514  
72-5810  
72-A413  
72-A514  
250  
Green (RoHS  
& no Sb/Br)  
4500  
4500  
4500  
4500  
Green (RoHS  
& no Sb/Br)  
Green (RoHS  
& no Sb/Br)  
Green (RoHS  
& no Sb/Br)  
-40 to 125  
-40 to 125  
Green (RoHS  
& no Sb/Br)  
Addendum-Page 1  
PACKAGE OPTION ADDENDUM  
www.ti.com  
7-Oct-2013  
Orderable Device  
Status Package Type Package Pins Package  
Eco Plan Lead/Ball Finish  
MSL Peak Temp  
Op Temp (°C)  
-40 to 125  
Device Marking  
Samples  
Drawing  
Qty  
(1)  
(2)  
(3)  
(4/5)  
LP3972SQX-E514/NOPB  
LP3972SQX-I414/NOPB  
LP3972SQX-I514/NOPB  
ACTIVE  
WQFN  
WQFN  
WQFN  
RSB  
40  
40  
40  
4500  
Green (RoHS  
& no Sb/Br)  
CU SN  
CU SN  
CU SN  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
72-E514  
ACTIVE  
ACTIVE  
RSB  
RSB  
4500  
4500  
Green (RoHS  
& no Sb/Br)  
-40 to 125  
72-I414  
72-I514  
Green (RoHS  
& no Sb/Br)  
-40 to 125  
(1) The marketing status values are defined as follows:  
ACTIVE: Product device recommended for new designs.  
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.  
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.  
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.  
OBSOLETE: TI has discontinued the production of the device.  
(2) Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability  
information and additional product content details.  
TBD: The Pb-Free/Green conversion plan has not been defined.  
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that  
lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.  
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between  
the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above.  
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight  
in homogeneous material)  
(3) MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.  
(4) There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.  
(5) Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation  
of the previous line and the two combined represent the entire Device Marking for that device.  
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information  
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and  
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.  
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.  
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.  
Addendum-Page 2  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
23-Sep-2013  
TAPE AND REEL INFORMATION  
*All dimensions are nominal  
Device  
Package Package Pins  
Type Drawing  
SPQ  
Reel  
Reel  
A0  
B0  
K0  
P1  
W
Pin1  
Diameter Width (mm) (mm) (mm) (mm) (mm) Quadrant  
(mm) W1 (mm)  
LP3972SQ-0514/NOPB  
LP3972SQ-5810/NOPB  
WQFN  
WQFN  
RSB  
RSB  
RSB  
RSB  
RSB  
RSB  
RSB  
RSB  
RSB  
RSB  
RSB  
RSB  
RSB  
RSB  
RSB  
RSB  
RSB  
RSB  
40  
40  
40  
40  
40  
40  
40  
40  
40  
40  
40  
40  
40  
40  
40  
40  
40  
40  
1000  
1000  
1000  
1000  
1000  
1000  
1000  
1000  
1000  
250  
178.0  
178.0  
178.0  
178.0  
178.0  
178.0  
178.0  
178.0  
178.0  
178.0  
178.0  
178.0  
330.0  
330.0  
330.0  
330.0  
330.0  
330.0  
12.4  
12.4  
12.4  
12.4  
12.4  
12.4  
12.4  
12.4  
12.4  
12.4  
12.4  
12.4  
12.4  
12.4  
12.4  
12.4  
12.4  
12.4  
5.3  
5.3  
5.3  
5.3  
5.3  
5.3  
5.3  
5.3  
5.3  
5.3  
5.3  
5.3  
5.3  
5.3  
5.3  
5.3  
5.3  
5.3  
5.3  
5.3  
5.3  
5.3  
5.3  
5.3  
5.3  
5.3  
5.3  
5.3  
5.3  
5.3  
5.3  
5.3  
5.3  
5.3  
5.3  
5.3  
1.3  
1.3  
1.3  
1.3  
1.3  
1.3  
1.3  
1.3  
1.3  
1.3  
1.3  
1.3  
1.3  
1.3  
1.3  
1.3  
1.3  
1.3  
8.0  
8.0  
8.0  
8.0  
8.0  
8.0  
8.0  
8.0  
8.0  
8.0  
8.0  
8.0  
8.0  
8.0  
8.0  
8.0  
8.0  
8.0  
12.0  
12.0  
12.0  
12.0  
12.0  
12.0  
12.0  
12.0  
12.0  
12.0  
12.0  
12.0  
12.0  
12.0  
12.0  
12.0  
12.0  
12.0  
Q1  
Q1  
Q1  
Q1  
Q1  
Q1  
Q1  
Q1  
Q1  
Q1  
Q1  
Q1  
Q1  
Q1  
Q1  
Q1  
Q1  
Q1  
LP3972SQ-A413/NOPB WQFN  
LP3972SQ-A514 WQFN  
LP3972SQ-A514/NOPB WQFN  
LP3972SQ-E514/NOPB WQFN  
LP3972SQ-I414/NOPB  
LP3972SQ-I514  
WQFN  
WQFN  
WQFN  
LP3972SQ-I514/NOPB  
LP3972SQE-A413/NOPB WQFN  
LP3972SQE-E514/NOPB WQFN  
LP3972SQE-I514/NOPB WQFN  
LP3972SQX-0514/NOPB WQFN  
LP3972SQX-5810/NOPB WQFN  
LP3972SQX-A413/NOPB WQFN  
LP3972SQX-A514/NOPB WQFN  
LP3972SQX-E514/NOPB WQFN  
LP3972SQX-I414/NOPB WQFN  
250  
250  
4500  
4500  
4500  
4500  
4500  
4500  
Pack Materials-Page 1  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
23-Sep-2013  
Device  
Package Package Pins  
Type Drawing  
SPQ  
Reel  
Reel  
A0  
B0  
K0  
P1  
W
Pin1  
Diameter Width (mm) (mm) (mm) (mm) (mm) Quadrant  
(mm) W1 (mm)  
LP3972SQX-I514/NOPB WQFN  
RSB  
40  
4500  
330.0  
12.4  
5.3  
5.3  
1.3  
8.0  
12.0  
Q1  
*All dimensions are nominal  
Device  
Package Type Package Drawing Pins  
SPQ  
Length (mm) Width (mm) Height (mm)  
LP3972SQ-0514/NOPB  
LP3972SQ-5810/NOPB  
LP3972SQ-A413/NOPB  
LP3972SQ-A514  
WQFN  
WQFN  
WQFN  
WQFN  
WQFN  
WQFN  
WQFN  
WQFN  
WQFN  
WQFN  
WQFN  
WQFN  
WQFN  
WQFN  
WQFN  
WQFN  
RSB  
RSB  
RSB  
RSB  
RSB  
RSB  
RSB  
RSB  
RSB  
RSB  
RSB  
RSB  
RSB  
RSB  
RSB  
RSB  
40  
40  
40  
40  
40  
40  
40  
40  
40  
40  
40  
40  
40  
40  
40  
40  
1000  
1000  
1000  
1000  
1000  
1000  
1000  
1000  
1000  
250  
203.0  
203.0  
203.0  
203.0  
203.0  
203.0  
203.0  
203.0  
203.0  
203.0  
203.0  
203.0  
367.0  
367.0  
367.0  
367.0  
190.0  
190.0  
190.0  
190.0  
190.0  
190.0  
190.0  
190.0  
190.0  
190.0  
190.0  
190.0  
367.0  
367.0  
367.0  
367.0  
41.0  
41.0  
41.0  
41.0  
41.0  
41.0  
41.0  
41.0  
41.0  
41.0  
41.0  
41.0  
35.0  
35.0  
35.0  
35.0  
LP3972SQ-A514/NOPB  
LP3972SQ-E514/NOPB  
LP3972SQ-I414/NOPB  
LP3972SQ-I514  
LP3972SQ-I514/NOPB  
LP3972SQE-A413/NOPB  
LP3972SQE-E514/NOPB  
LP3972SQE-I514/NOPB  
LP3972SQX-0514/NOPB  
LP3972SQX-5810/NOPB  
LP3972SQX-A413/NOPB  
LP3972SQX-A514/NOPB  
250  
250  
4500  
4500  
4500  
4500  
Pack Materials-Page 2  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
23-Sep-2013  
Device  
Package Type Package Drawing Pins  
SPQ  
Length (mm) Width (mm) Height (mm)  
LP3972SQX-E514/NOPB  
LP3972SQX-I414/NOPB  
LP3972SQX-I514/NOPB  
WQFN  
WQFN  
WQFN  
RSB  
RSB  
RSB  
40  
40  
40  
4500  
4500  
4500  
367.0  
367.0  
367.0  
367.0  
367.0  
367.0  
35.0  
35.0  
35.0  
Pack Materials-Page 3  
MECHANICAL DATA  
RSB0040A  
SQF40A (Rev B)  
www.ti.com  
IMPORTANT NOTICE  
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TI warrants performance of its components to the specifications applicable at the time of sale, in accordance with the warranty in TI’s terms  
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