TPS62674 [TI]

500-mA, 6-MHz HIGH-EFFICIENCY STEP-DOWN CONVERTER IN LOW PROFILE CHIP SCALE PACKAGING; 500毫安, 6 MHz的高效率降压转换器低姿态芯片级封装
TPS62674
型号: TPS62674
厂家: TEXAS INSTRUMENTS    TEXAS INSTRUMENTS
描述:

500-mA, 6-MHz HIGH-EFFICIENCY STEP-DOWN CONVERTER IN LOW PROFILE CHIP SCALE PACKAGING
500毫安, 6 MHz的高效率降压转换器低姿态芯片级封装

转换器 功效
文件: 总28页 (文件大小:755K)
中文:  中文翻译
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CSP-6  
TPS6267x  
www.ti.com  
SLVS952 APRIL 2010  
500-mA, 6-MHz HIGH-EFFICIENCY STEP-DOWN CONVERTER  
IN LOW PROFILE CHIP SCALE PACKAGING (HEIGHT < 0.4mm)  
Check for Samples: TPS6267x  
1
FEATURES  
APPLICATIONS  
23  
92% Efficiency at 6MHz Operation  
Cell Phones, Smart-Phones  
Camera Module Embedded Power  
Digital TV, WLAN, GPS and Bluetooth™  
Applications  
17mA Quiescent Current  
Wide VIN Range From 2.3V to 4.8V  
6MHz Regulated Frequency Operation  
Spread Spectrum, PWM Frequency Dithering  
Best in Class Load and Line Transient  
±2% Total DC Voltage Accuracy  
Low Ripple Light-Load PFM Mode  
>50dB VIN PSRR (1kHz to 10kHz)  
Simple Logic Enable Inputs  
DC/DC Micro Modules  
DESCRIPTION  
The TPS6267x device is  
a
high-frequency  
synchronous step-down dc-dc converter optimized for  
battery-powered portable applications. Intended for  
low-power applications, the TPS6267x supports up to  
500-mA load current, and allows the use of low cost  
chip inductor and capacitors.  
Supports External Clock Presence Detect  
Enable Input  
Three Surface-Mount External Components  
Required (One 0603 MLCC Inductor, Two 0402  
Ceramic Capacitors)  
With a wide input voltage range of 2.3V to 4.8V, the  
device supports applications powered by Li-Ion  
batteries with extended voltage range. Different fixed  
voltage output versions are available from 1.0V to  
2.3V.  
Complete Sub 0.33-mm Component Profile  
Solution  
Total Solution Size <10 mm2  
The TPS6267x operates at a regulated 6-MHz  
switching frequency and enters the power-save mode  
operation at light load currents to maintain high  
efficiency over the entire load current range.  
Available in a 6-Pin NanoFree™ (CSP)  
Ultra-Thin Packaging, 0,4mm Max. Height  
The PFM mode extends the battery life by reducing  
the quiescent current to 17mA (typ) during light load  
operation. For noise-sensitive applications, the device  
has PWM spread spectrum capability providing a  
lower noise regulated output, as well as low noise at  
the input. These features, combined with high PSRR  
and AC load regulation performance, make this  
device suitable to replace a linear regulator to obtain  
better power conversion efficiency.  
100  
200  
V = 3.6 V,  
I
90  
V
= 1.8 V  
180  
O
80  
70  
60  
50  
40  
30  
20  
160  
140  
120  
100  
80  
V
V
OUT  
1.8 V @ 500mA  
TPS62671  
VIN  
BAT  
2.3 V .. 4.8 V  
L
SW  
0.47 mH  
60  
C
I
40  
FB  
EN  
C
O
2.2 mF  
10  
0
4.7 mF  
20  
0
MODE  
GND  
0.1  
1
10  
100  
1000  
I
- Load Current - mA  
O
Figure 2. Smallest Solution Size Application  
Figure 1. Efficiency vs. Load Current  
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
3
NanoFree is a trademark of Texas Instruments.  
Bluetooth is a trademark of Bluetooth SIG, Inc.  
UNLESS OTHERWISE NOTED this document contains  
PRODUCTION DATA information current as of publication date.  
Products conform to specifications per the terms of Texas  
Instruments standard warranty. Production processing does not  
necessarily include testing of all parameters.  
Copyright © 2010, Texas Instruments Incorporated  
TPS6267x  
SLVS952 APRIL 2010  
www.ti.com  
This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with  
appropriate precautions. Failure to observe proper handling and installation procedures can cause damage.  
ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more  
susceptible to damage because very small parametric changes could cause the device not to meet its published specifications.  
ORDERING INFORMATION(1)  
PACKAGE  
MARKING  
CHIP CODE  
PART  
NUMBER  
OUTPUT  
DEVICE  
SPECIFIC FEATURE  
TA  
ORDERING(3)  
VOLTAGE(2)  
TPS62671(4)  
TPS62672(4)  
1.8V  
1.5V  
PWM Spread Spectrum Modulation  
PWM Spread Spectrum Modulation  
TPS62671YFD  
TPS62672YFD  
NZ  
OA  
PWM Spread Spectrum Modulation  
PWM Operation Only  
-40°C to 85°C  
TPS62674  
1.26V  
TPS62674YFD  
PN  
PM  
Output Capacitor Discharge  
TPS62676(4)  
TPS62677(4)  
2.1V  
1.2V  
PWM Spread Spectrum Modulation  
PWM Spread Spectrum Modulation  
TPS62676YFD  
TPS62677YFD  
(1) For the most current package and ordering information, see the Package Option Addendum at the end of this document, or see the TI  
website at www.ti.com.  
(2) Internal tap points are available to facilitate output voltages in 25mV increments.  
(3) The YFD package is available in tape and reel. Add a R suffix (e.g. TPS62670YFDR) to order quantities of 3000 parts. Add a T suffix  
(e.g. TPS62670YFDT) to order quantities of 250 parts.  
(4) Product preview.  
ABSOLUTE MAXIMUM RATINGS  
over operating free-air temperature range (unless otherwise noted)(1)  
UNIT  
Voltage at VIN(2), SW(3)  
Voltage at FB(3)  
–0.3 V to 6 V  
–0.3 V to 3.6 V  
–0.3 V to VI + 0.3 V  
Internally limited  
–40°C to 85°C  
150°C  
VI  
(3)  
Voltage at EN, MODE  
Power dissipation  
TA  
Operating temperature range(4)  
Maximum operating junction temperature  
Storage temperature range  
Human body model  
TJ (max)  
Tstg  
–65°C to 150°C  
2 kV  
(5)  
ESD rating  
Charge device model  
1 kV  
Machine model  
200 V  
(1) Stresses beyond those listed under absolute maximum ratings may cause permanent damage to the device. These are stress ratings  
only and functional operation of the device at these or any other conditions beyond those indicated under recommended operating  
conditions is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.  
(2) Operation above 4.8V input voltage for extended periods may affect device reliability.  
(3) All voltage values are with respect to network ground terminal.  
(4) 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)), 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 (qJA), as given by the following equation: TA(max)= TJ(max)–(qJA X PD(max)). To achieve optimum performance, it is  
recommended to operate the device with a maximum junction temperature of 105°C.  
(5) The human body model is a 100-pF capacitor discharged through a 1.5-kresistor into each pin. The machine model is a 200-pF  
capacitor discharged directly into each pin.  
2
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Copyright © 2010, Texas Instruments Incorporated  
Product Folder Link(s): TPS6267x  
TPS6267x  
www.ti.com  
SLVS952 APRIL 2010  
RECOMMENDED OPERATING CONDITIONS  
MIN  
2.3  
0
NOM  
MAX UNIT  
VI  
IO  
L
Input voltage range  
Output current range  
Inductance  
4.8(1)  
500  
1.8  
V
mA  
µH  
µF  
°C  
°C  
0.3  
1.4  
–40  
–40  
CO  
TA  
TJ  
Output capacitance  
Ambient temperature  
Operating junction temperature  
2.5  
12  
+85  
+125  
(1) Operation above 4.8V input voltage for extended periods may affect device reliability.  
DISSIPATION RATINGS(1)  
POWER RATING  
A 25°C  
DERATING FACTOR  
ABOVE TA = 25°C  
(2)  
(2)  
PACKAGE  
RqJA  
RqJB  
T
YFD-6  
125°C/W  
53°C/W  
800mW  
8mW/°C  
(1) Maximum power dissipation is a function of TJ(max), qJA and TA. The maximum allowable power dissipation at any allowable ambient  
temperature is PD = [TJ(max)–TA] / qJA  
.
(2) This thermal data is measured with high-K board (4 layers board according to JESD51-7 JEDEC standard).  
ELECTRICAL CHARACTERISTICS  
Minimum and maximum values are at VI = 2.3V to 5.5V, VO = 1.8V, EN = 1.8V, AUTO mode and TA = –40°C to 85°C; Circuit  
of Parameter Measurement Information section (unless otherwise noted). Typical values are at VI = 3.6V, VO = 1.8V, EN =  
1.8V, AUTO mode and TA = 25°C (unless otherwise noted).  
PARAMETER  
TEST CONDITIONS  
MIN  
TYP  
MAX UNIT  
SUPPLY CURRENT  
TPS62671  
TPS62672  
TPS62676  
TPS62677  
IO = 0mA. Device not switching  
17  
40  
mA  
Operating quiescent  
current  
IQ  
TPS62671  
TPS62674  
IO = 0mA, PWM mode  
IO = 0mA, PWM mode  
EN = GND  
5.5  
5.0  
mA  
mA  
mA  
V
I(SD)  
Shutdown current  
0.2  
1
UVLO  
Undervoltage lockout threshold  
2.05  
2.1  
ENABLE, MODE  
High-level input  
voltage  
VIH  
VIL  
Ilkg  
1.0  
V
V
TPS62671  
TPS62672  
TPS62676  
TPS62677  
Low-level input  
voltage  
0.4  
1.5  
Input leakage  
current  
Input connected to GND or VIN  
0.01  
mA  
V
High-level input  
voltage (ENABLE)  
1.26  
1.0  
VIH  
High-level input  
voltage (MODE)  
V
TPS62674  
Low-level input  
voltage (ENABLE)  
VIL  
Ilkg  
CIN  
0.54  
1.5  
V
Input leakage  
current  
Input connected to GND or VIN  
0.01  
5
mA  
pF  
MHz  
%
Input capacitance  
(ENABLE)  
Clock presence  
detect frequency  
4
27  
60  
EXTCLK  
Clock presence  
detect duty cycle  
40  
Copyright © 2010, Texas Instruments Incorporated  
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Product Folder Link(s): TPS6267x  
TPS6267x  
SLVS952 APRIL 2010  
www.ti.com  
ELECTRICAL CHARACTERISTICS (continued)  
Minimum and maximum values are at VI = 2.3V to 5.5V, VO = 1.8V, EN = 1.8V, AUTO mode and TA = –40°C to  
85°C; Circuit of Parameter Measurement Information section (unless otherwise noted). Typical values are at VI =  
3.6V, VO = 1.8V, EN = 1.8V, AUTO mode and TA = 25°C (unless otherwise noted).  
PARAMETER  
TEST CONDITIONS  
MIN  
TYP  
MAX UNIT  
POWER SWITCH  
rDS(on)  
Ilkg  
VI = V(GS) = 3.6V. PWM mode  
170  
230  
mΩ  
mΩ  
P-channel MOSFET on resistance  
P-channel leakage current, PMOS  
N-channel MOSFET on resistance  
N-channel leakage current, NMOS  
VI = V(GS) = 2.5V. PWM mode  
V(DS) = 5.5V, -40°C TJ 85°C  
VI = V(GS) = 3.6V. PWM mode  
VI = V(GS) = 2.5V. PWM mode  
V(DS) = 5.5V, -40°C TJ 85°C  
1
mA  
mΩ  
mΩ  
mA  
120  
180  
rDS(on)  
Ilkg  
2
150  
Discharge resistor for power-down  
sequence  
rDIS  
70  
1000  
12  
P-MOS current limit  
2.3V VI 4.8V. Open loop  
900  
1150  
mA  
mA  
Input current limit under short-circuit  
conditions  
VO shorted to ground  
Thermal shutdown  
140  
10  
°C  
°C  
Thermal shutdown hysteresis  
OSCILLATOR  
TPS62671  
TPS62672  
TPS62676  
TPS62677  
Oscillator center  
frequency  
IO = 0mA. PWM operation  
IO = 0mA. PWM operation  
5.4  
4.9  
6
6.6  
6.0  
MHz  
MHz  
fSW  
Oscillator center  
frequency  
TPS62674  
5.45  
OUTPUT  
2.3V VI 4.8V, 0mA IO 500 mA  
PFM/PWM operation  
0.98×VNOM  
0.98×VNOM  
0.98×VNOM  
0.98×VNOM  
VNOM  
VNOM  
VNOM  
VNOM  
1.03×VNOM  
1.04×VNOM  
1.02×VNOM  
1.02×VNOM  
V
V
V
V
TPS62671  
TPS62672  
TPS62676  
TPS62677  
2.3V VI 5.5V, 0mA IO 500 mA  
PFM/PWM operation  
Regulated DC  
output voltage  
2.3V VI 5.5V, 0mA IO 500 mA  
PWM operation  
V(OUT)  
2.3V VI 5.5V, 0mA IO 500 mA  
PWM operation  
TPS62674  
TPS6267X  
Line regulation  
Load regulation  
VI = VO + 0.5V (min 2.3V) to 5.5V, IO = 200 mA  
IO = 0mA to 500 mA. PWM operation  
0.23  
–0.00045  
480  
%/V  
%/mA  
kΩ  
Feedback input resistance  
TPS62671  
IO = 1mA, VO = 1.8 V  
IO = 1mA, VO = 1.2 V  
20  
mVPP  
mVPP  
Power-save mode  
ripple voltage  
ΔVO  
TPS62677  
TPS62671  
24  
Power Supply  
Rejection Ratio  
PSRR  
f = 10kHz, IO = 150mA. PWM mode  
TBD  
dB  
TPS62671  
TPS62674  
IO = 0mA, Time from active EN to VO  
130  
125  
ms  
ms  
Start-up time  
IO = 0mA, Time from EXTCLK clock active to VO  
IO = 0mA, Time from EXTCLK clock inactive to VO  
down  
Shutdown time  
TPS62674  
1.2  
ms  
4
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Copyright © 2010, Texas Instruments Incorporated  
Product Folder Link(s): TPS6267x  
TPS6267x  
www.ti.com  
SLVS952 APRIL 2010  
PIN ASSIGNMENTS  
TPS6267x  
CSP-6  
(TOP VIEW)  
TPS6267x  
CSP-6  
(BOTTOM VIEW)  
VIN  
EN  
A2  
B2  
C2  
A1  
B1  
C1  
A1  
A2  
B2  
VIN  
EN  
MODE  
SW  
MODE  
B1  
C1  
SW  
FB  
GND  
C2 GND  
FB  
TERMINAL FUNCTIONS  
TERMINAL  
I/O  
DESCRIPTION  
NAME  
FB  
NO.  
C1  
I
I
Output feedback sense input. Connect FB to the converter’s output.  
Power supply input.  
VIN  
A2  
This is the switch pin of the converter and is connected to the drain of the internal Power  
MOSFETs.  
SW  
EN  
B1  
B2  
I/O  
This is the enable pin of the device. Connecting this pin to ground forces the device into  
shutdown mode. Pulling this pin to VI enables the device. If an external clock (4MHz to 27MHz) is  
detected the device will automatically power up. This pin must not be left floating and must be  
terminated.  
I
This is the mode selection pin of the device. This pin must not be left floating and must be  
terminated.  
MODE = LOW: The device is operating in regulated frequency pulse width modulation mode  
(PWM) at high-load currents and in pulse frequency modulation mode (PFM) at light load  
currents.  
MODE  
GND  
A1  
C2  
I
MODE = HIGH: Low-noise mode enabled, regulated frequency PWM operation forced.  
Ground pin.  
FUNCTIONAL BLOCK DIAGRAM  
MODE  
EN  
VIN  
Undervoltage  
Lockout  
Bias Supply  
VIN  
Soft-Start  
Negative Inductor  
Current Detect  
Bandgap  
V
= 0.8 V  
Power Save Mode  
Switching Logic  
REF  
Current Limit  
Detect  
Thermal  
Shutdown  
Frequency  
Control  
R
1
FB  
-
Gate Driver  
SW  
Anti  
R
V
2
REF  
Shoot-Through  
+
GND  
Copyright © 2010, Texas Instruments Incorporated  
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Product Folder Link(s): TPS6267x  
TPS6267x  
SLVS952 APRIL 2010  
www.ti.com  
PARAMETER MEASUREMENT INFORMATION  
TPS6267x  
L
SW  
VIN  
V
O
FB  
EN  
V
C
I
I
C
O
MODE  
GND  
List of components:  
L = MURATA LQM21PN1R0NGR  
CI = MURATA GRM155R60J225ME15 (2.2mF, 6.3V, 0402, X5R)  
CO = MURATA GRM155R60J475M (4.7mF, 6.3V, 0402, X5R)  
6
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Copyright © 2010, Texas Instruments Incorporated  
Product Folder Link(s): TPS6267x  
TPS6267x  
www.ti.com  
SLVS952 APRIL 2010  
TYPICAL CHARACTERISTICS  
Table of Graphs  
FIGURE  
3, 4, 5, 6  
7
vs Load current  
vs Input voltage  
h
Efficiency  
Peak-to-peak output ripple voltage  
vs Load current  
8, 9  
Combined line/load transient  
response  
10, 11  
12, 13, 14, 15,  
16, 17, 18  
Load transient response  
AC load transient response  
DC output voltage  
19  
20, 21, 22  
23  
VO  
vs Load current  
vs Input voltage  
vs Input voltage  
vs Input voltage  
vs Input voltage  
vs. Frequency  
PFM/PWM boundaries  
Quiescent current  
IQ  
24  
PWM switching frequency  
PFM switching frequency  
Power supply rejection ratio  
PWM operation  
25, 26  
27  
fs  
PSRR  
28  
29, 30  
31  
Power-save mode operation  
Start-up  
32, 33  
34  
Shutdown  
Spurious output noise (PWM mode)  
Spurious output noise (PFM mode)  
vs. Frequency  
vs. Frequency  
35, 36, 38  
37  
EFFICIENCY  
vs  
EFFICIENCY  
vs  
LOAD CURRENT  
LOAD CURRENT  
100  
100  
90  
V = 2.7 V  
I
V
= 1.2 V  
V
= 1.8 V  
O
O
PFM/PWM Operation  
90  
80  
70  
60  
50  
80  
70  
60  
50  
V = 3.6 V  
I
V = 3.6 V  
I
PFM/PWM Operation  
PFM/PWM Operation  
V
= 4.2 V  
I
V = 2.7 V  
I
PFM/PWM Operation  
V
= 4.2 V  
I
PFM/PWM Operation  
PFM/PWM Operation  
V = 3.6 V  
I
40  
30  
20  
10  
40  
30  
20  
Forced PWM Operation  
V = 3.6 V  
I
Forced PWM Operation  
10  
0
0
0.1  
1
10  
- Load Current - mA  
100  
1000  
0.1  
1
10  
- Load Current - mA  
100  
1000  
I
I
O
O
Figure 3.  
Figure 4.  
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TPS6267x  
SLVS952 APRIL 2010  
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TYPICAL CHARACTERISTICS (continued)  
EFFICIENCY  
EFFICIENCY  
vs  
vs  
LOAD CURRENT  
LOAD CURRENT  
90  
89  
88  
87  
86  
85  
84  
83  
82  
81  
80  
79  
78  
77  
76  
75  
74  
73  
72  
71  
100  
L = muRata LQM21PN1R0NGR  
L = muRata LQM21PN1R0MC0  
V
= 1.26 V  
O
90  
V = 2.7 V  
I
80  
70  
60  
50  
PWM Operation  
V = 3.6 V  
I
PWM Operation  
V
= 4.2 V  
40  
30  
20  
10  
I
L = muRata  
LQM18PN1R5-B35  
PWM Operation  
V - 3.6 V,  
I
V
= 1.2 V  
O
PFM/PWM Operation  
0
1
10  
100 1000  
1
10  
100  
- Load Current - mA  
1000  
I
- Load Current - mA  
I
O
O
Figure 5.  
Figure 6.  
EFFICIENCY  
vs  
PEAK-TO-PEAK OUTPUT RIPPLE VOLTAGE  
vs  
INPUT VOLTAGE  
LOAD CURRENT  
90  
88  
20  
18  
16  
14  
12  
10  
8
I
= 10 mA  
I
= 100 mA  
O
O
V
= 1.8 V  
O
I
= 300 mA  
O
86  
84  
82  
80  
78  
76  
74  
I
= 1 mA  
O
6
4
V
= 1.2 V  
O
PFM/PWM Operation  
2
72  
70  
0
2.5  
2.8  
3.1  
3.4  
3.7 4.0 4.3 4.6 4.8  
0
50  
100  
I
150  
200  
- Load Current - mA  
250  
300  
350  
V - Input Voltage - V  
I
O
Figure 7.  
Figure 8.  
8
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Copyright © 2010, Texas Instruments Incorporated  
Product Folder Link(s): TPS6267x  
TPS6267x  
www.ti.com  
SLVS952 APRIL 2010  
TYPICAL CHARACTERISTICS (continued)  
PEAK-TO-PEAK OUTPUT RIPPLE VOLTAGE  
vs  
LOAD CURRENT  
COMBINED LINE/LOAD TRANSIENT RESPONSE  
34  
32  
30  
28  
26  
24  
22  
20  
18  
16  
14  
12  
10  
8
V
= 1.2 V  
V = 3.6 V,  
O
I
V
= 1.2 V  
O
V = 4.8 V  
I
V = 3.6 V  
I
V = 2.5 V  
I
50 to 350 mA Load Step  
3.3V to 3.9V Line Step  
MODE = Low  
6
4
2
0
0
50  
100  
I
150  
200  
- Load Current - mA  
250  
300  
350  
O
Figure 9.  
Figure 10.  
LOAD TRANSIENT RESPONSE IN  
PFM/PWM OPERATION  
COMBINED LINE/LOAD TRANSIENT RESPONSE  
V = 3.6 V,  
I
V = 3.6 V,  
I
V
= 1.2 V  
V = 1.2 V  
O
O
5 to 150 mA Load Step  
50 to 350 mA Load Step  
2.7V to 3.3V Line Step  
MODE = Low  
MODE = Low  
Figure 11.  
Figure 12.  
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TYPICAL CHARACTERISTICS (continued)  
LOAD TRANSIENT RESPONSE IN  
PFM/PWM OPERATION  
LOAD TRANSIENT RESPONSE IN  
PFM/PWM OPERATION  
V = 3.6 V,  
I
V = 2.7 V,  
I
V
= 1.2 V  
V = 1.2 V  
O
50 to 350 mA Load Step  
50 to 350 mA Load Step  
O
MODE = Low  
MODE = Low  
Figure 13.  
Figure 14.  
LOAD TRANSIENT RESPONSE IN  
PFM/PWM OPERATION  
LOAD TRANSIENT RESPONSE IN  
PFM/PWM OPERATION  
V = 4.8 V,  
V = 3.6 V,  
I
I
V
= 1.2 V  
V = 1.2 V  
O
50 to 350 mA Load Step  
O
150 to 500 mA Load Step  
MODE = Low  
MODE = Low  
Figure 15.  
Figure 16.  
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TYPICAL CHARACTERISTICS (continued)  
LOAD TRANSIENT RESPONSE IN  
PFM/PWM OPERATION  
LOAD TRANSIENT RESPONSE  
IN PFM/PWM OPERATION  
V = 2.7 V,  
I
V = 4.8 V,  
I
V
= 1.2 V  
V
= 1.2 V  
O
O
150 to 500 mA Load Step  
150 to 500 mA Load Step  
MODE = Low  
MODE = Low  
Figure 17.  
Figure 18.  
DC OUTPUT VOLTAGE  
vs  
AC LOAD TRANSIENT RESPONSE  
LOAD CURRENT  
1.836  
1.818  
1.8  
V = 1.8 V  
O
PFM/PWM Operation  
V = 3.6 V,  
I
V
= 1.2 V  
O
5 to 300 mA Load Sweep  
V = 4.5 V  
I
V = 3.6 V  
I
V = 2.7 V  
I
1.782  
1.764  
MODE = Low  
0.1  
1
10  
- Load Current - mA  
100  
1000  
I
O
Figure 19.  
Figure 20.  
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TYPICAL CHARACTERISTICS (continued)  
DC OUTPUT VOLTAGE  
OUTPUT VOLTAGE  
vs  
vs  
LOAD CURRENT  
LOAD CURRENT  
1.224  
1.285  
1.273  
1.260  
V
= 1.2 V  
V
= 1.26 V  
O
PFM/PWM Operation  
O
PWM Operation  
1.212  
1.200  
V = 3.6 V  
I
V = 4.5 V  
I
V
= 4.5 V  
I
V = 3.6 V  
I
V = 2.7 V  
I
V = 2.7 V  
I
1.188  
1.176  
1.247  
1.235  
0.1  
1
10  
- Load Current - mA  
100  
1000  
0.1  
1
10  
- Load Current - mA  
100  
1000  
I
I
O
O
Figure 21.  
Figure 22.  
QUIESCENT CURRENT  
vs  
PFM/PWM BOUNDARIES  
= 1.2 V  
INPUT VOLTAGE  
160  
150  
140  
130  
120  
110  
100  
90  
28  
26  
24  
22  
20  
18  
16  
14  
12  
10  
8
V
Always PWM  
O
T
= 85°C  
A
T
= 25°C  
PWM to PFM  
Mode Change  
A
The Switching Mode  
Changes at  
These Borders  
80  
70  
60  
T
= -40°C  
A
50  
40  
PFM to PWM  
Mode Change  
6
30  
Always PFM  
4
20  
2
10  
0
2.7  
0
3
3.3  
3.6  
3.9  
4.2  
4.5  
4.8  
2.7  
3
3.3  
3.6  
3.9  
V - Input Voltage - V  
4.2  
4.5  
4.8  
V - Input Voltage - V  
I
I
Figure 23.  
Figure 24.  
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TYPICAL CHARACTERISTICS (continued)  
PWM SWITCHING FREQUENCY  
PWM SWITCHING FREQUENCY  
vs  
vs  
INPUT VOLTAGE  
INPUT VOLTAGE  
6.5  
6
6.5  
6.3  
6.1  
5.9  
5.7  
5.5  
5.3  
5.1  
4.9  
4.7  
4.5  
I
= 150 mA  
O
V
= 1.2 V  
O
I
Ranging from 0 to 500 mA  
O
I
= 500 mA  
= 400 mA  
O
5.5  
5
I
O
I
= 300 mA  
O
4.5  
4
3.5  
3
V
= 1.8 V  
O
2.5  
2.5 2.7 2.9 3.1 3.3 3.5 3.7 3.9 4.1 4.3 4.5  
2.5 2.7 2.9 3.1 3.3 3.5 3.7 3.9 4.1 4.3 4.5  
V - Input Voltage - V  
V - Input Voltage - V  
I
I
Figure 25.  
Figure 26.  
PFM SWITCHING FREQUENCY  
POWER SUPPLY REJECTION RATIO  
vs  
vs  
INPUT VOLTAGE  
FREQUENCY  
6.5  
6
60  
V = 3.6 V,  
I
V
= 1.2 V  
O
55  
50  
V
= 1.8 V  
O
5.5  
V = 2.7 V  
I
5
4.5  
4
45  
40  
I
= 150 mA  
V = 3.6 V  
I
O
35  
30  
25  
V = 4.8 V  
I
3.5  
3
2.5  
2
20  
15  
1.5  
1
10  
PFM/PWM Operation  
0.5  
5
0
0
1000  
0
20  
40  
60  
- Load Current - mA  
80  
100 120 140 160  
0.1  
1
10  
100  
10000  
I
f - Frequency - kHz  
O
Figure 27.  
Figure 28.  
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TYPICAL CHARACTERISTICS (continued)  
PWM OPERATION  
PWM OPERATION  
SSFM MODULATION  
V = 3.6 V,  
V = 3.6 V,  
I
I
V
I
= 1.2 V,  
V
I
= 1.2 V,  
O
O
= 200 mA  
= 150 mA  
O
O
MODE = Low  
MODE = Low  
Figure 29.  
POWER-SAVE MODE OPERATION  
Figure 30.  
START-UP  
V = 3.6 V, V = 1.2V, I = 40 mA  
I
O
O
V = 3.6 V,  
I
V
I
= 1.2 V,  
O
= 0 mA  
O
MODE = Low  
MODE = Low  
Figure 31.  
Figure 32.  
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TYPICAL CHARACTERISTICS (continued)  
SHUT-DOWN (RF CLOCK)  
START-UP (RF CLOCK)  
vs  
V = 3.6 V,  
I
V
I
= 1.2 V,  
O
= 0 mA  
O
V = 3.6 V,  
I
V
I
= 1.2 V,  
O
= 0 mA  
O
MODE = High  
MODE = High  
Figure 33.  
Figure 34.  
SPURIOUS OUTPUT NOISE (PWM MODE)  
SPURIOUS OUTPUT NOISE (PWM MODE)  
vs  
vs  
FREQUENCY  
FREQUENCY  
350 m  
300 m  
220 m  
200 m  
180 m  
160 m  
140 m  
120 m  
100 m  
V = 3.6 V  
I
V
= 1.26 V  
= 12 Ω  
O
V
= 1.26 V  
= 12 Ω  
R
O
L
R
L
250 m  
200 m  
150 m  
100 m  
V = 4.2 V  
I
80 m  
60 m  
40 m  
V = 3.6 V  
I
V = 2.7 V  
I
50 m  
20 m  
3.5 n  
2.2 n  
0
Span = 4 MHz  
40  
4.15  
Span = 250 kHz  
6.65  
f - Frequency - MHz  
f - Frequency - MHz  
Figure 35.  
Figure 36.  
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TYPICAL CHARACTERISTICS (continued)  
SPURIOUS OUTPUT NOISE (PFM MODE)  
SPURIOUS OUTPUT NOISE (PWM MODE)  
vs  
vs  
FREQUENCY  
FREQUENCY  
350 m  
300 m  
V
= 1.8 V  
= 12 Ω  
O
R
L
250 m  
200 m  
150 m  
100 m  
50 m  
V = 3.6 V  
I
V = 4.2 V  
I
V = 2.7 V  
I
3.5 n  
0
Span = 10 MHz  
100  
f - Frequency - MHz  
Figure 37.  
Figure 38.  
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DETAILED DESCRIPTION  
OPERATION  
The TPS6267x is a synchronous step-down converter typically operates at a regulated 6-MHz frequency pulse  
width modulation (PWM) at moderate to heavy load currents. At light load currents, the TPS6267x converter  
operates in power-save mode with pulse frequency modulation (PFM).  
The converter uses a unique frequency locked ring oscillating modulator to achieve best-in-class load and line  
response and allows the use of tiny inductors and small ceramic input and output capacitors. At the beginning of  
each switching cycle, the P-channel MOSFET switch is turned on and the inductor current ramps up rising the  
output voltage until the main comparator trips, then the control logic turns off the switch.  
One key advantage of the non-linear architecture is that there is no traditional feed-back loop. The loop response  
to change in VO is essentially instantaneous, which explains the transient response. The absence of a traditional,  
high-gain compensated linear loop means that the TPS6267x is inherently stable over a range of L and CO.  
Although this type of operation normally results in a switching frequency that varies with input voltage and load  
current, an internal frequency lock loop (FLL) holds the switching frequency constant over a large range of  
operating conditions.  
Combined with best in class load and line transient response characteristics, the low quiescent current of the  
device (ca. 17mA) allows to maintain high efficiency at light load, while preserving fast transient response for  
applications requiring tight output regulation.  
Using the YFD package allows for a low profile solution size (0.4mm max height, including external components).  
The recommended external components are stated within the application information. The maximum output  
current is 500mA when these specific low profile external components are used.  
SWITCHING FREQUENCY  
The magnitude of the internal ramp, which is generated from the duty cycle, reduces for duty cycles either set of  
50%. Thus, there is less overdrive on the main comparator inputs which tends to slow the conversion down. The  
intrinsic maximum operating frequency of the converter is about 10MHz to 12MHz, which is controlled to circa.  
6MHz by a frequency locked loop.  
When high or low duty cycles are encountered, the loop runs out of range and the conversion frequency falls  
below 6MHz. The tendency is for the converter to operate more towards a "constant inductor peak current" rather  
than a "constant frequency". In addition to this behavior which is observed at high duty cycles, it is also noted at  
low duty cycles.  
When the converter is required to operate towards the 6MHz nominal at extreme duty cycles, the application can  
be assisted by decreasing the ratio of inductance (L) to the output capacitor's equivalent serial inductance (ESL).  
This increases the ESL step seen at the main comparator's feed-back input thus decreasing its propagation  
delay, hence increasing the switching frequency.  
POWER-SAVE MODE  
If the load current decreases, the converter will enter Power Save Mode operation automatically (does not apply  
for TPS62674). During power-save mode the converter operates in discontinuous current (DCM) single-pulse  
PFM mode, which produces low output ripple compared with other PFM architectures.  
When in power-save mode, the converter resumes its operation when the output voltage trips below the nominal  
voltage. It ramps up the output voltage with a minimum of one pulse and goes into power-save mode when the  
inductor current has returned to a zero steady state. The PFM on-time varies inversely proportional to the input  
voltage and proportional to the output voltage giving the regulated switching frequency when in steady-state.  
PFM mode is left and PWM operation is entered as the output current can no longer be supported in PFM mode.  
As a consequence, the DC output voltage is typically positioned ca. 0.5% above the nominal output voltage and  
the transition between PFM and PWM is seamless.  
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PFM Mode at Light Load  
PFM Ripple  
Nominal DC Output Voltage  
PWM Mode at Heavy Load  
Figure 39. Operation in PFM Mode and Transfer to PWM Mode  
MODE SELECTION  
The MODE pin allows to select the operating mode of the device. Connecting this pin to GND enables the  
automatic PWM and power-save mode operation. The converter operates in regulated frequency PWM mode at  
moderate to heavy loads and in the PFM mode during light loads, which maintains high efficiency over a wide  
load current range.  
Pulling the MODE pin high forces the converter to operate in the PWM mode even at light load currents. The  
advantage is that the converter modulates its switching frequency according to a spread spectrum PWM  
modulation technique allowing simple filtering of the switching harmonics in noise-sensitive applications. In this  
mode, the efficiency is lower compared to the power-save mode during light loads. Notice that the TPS62674  
device only permits PWM operation and required the MODE input to be tied high.  
For additional flexibility, it is possible to switch from power-save mode to PWM mode during operation. This  
allows efficient power management by adjusting the operation of the converter to the specific system  
requirements.  
SPREAD SPECTRUM, PWM FREQUENCY DITHERING  
The goal is to spread out the emitted RF energy over a larger frequency range so that the resulting EMI is similar  
to white noise. The end result is a spectrum that is continuous and lower in peak amplitude, making it easier to  
comply with electromagnetic interference (EMI) standards and with the power supply ripple requirements in  
cellular and non-cellular wireless applications. Radio receivers are typically susceptible to narrowband noise that  
is focused on specific frequencies.  
Switching regulators can be particularly troublesome in applications where electromagnetic interference (EMI) is  
a concern. Switching regulators operate on a cycle-by-cycle basis to transfer power to an output. In most cases,  
the frequency of operation is either fixed or regulated, based on the output load. This method of conversion  
creates large components of noise at the frequency of operation (fundamental) and multiples of the operating  
frequency (harmonics).  
The spread spectrum architecture varies the switching frequency by ca. ±10% of the nominal switching frequency  
thereby significantly reducing the peak radiated and conducting noise on both the input and output supplies. The  
frequency dithering scheme is modulated with a triangle profile and a modulation frequency fm.  
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0 dBV  
F
Dfc  
ENV,PEAK  
Dfc  
Non-modulated harmonic  
F
1
Side-band harmonics  
window after modulation  
0 dBVref  
B = 2×fm ×(1+ mf )= 2×(Dfc + fm )  
Bh = 2×fm ×(1+ mf ×h)  
B = 2×fm ×(1+ mf )= 2×(Dfc + fm )  
Figure 40. Spectrum of a Frequency Modulated  
Sin. Wave with Sinusoidal Variation in Time  
Figure 41. Spread Bands of Harmonics in  
Modulated Square Signals  
The above figures show that after modulation the sideband harmonic is attenuated compared to the  
non-modulated harmonic, and the harmonic energy is spread into a certain frequency band. The higher the  
modulation index (mf) the larger the attenuation.  
δ ´ ƒc  
mƒ  
=
ƒm  
(1)  
With:  
fc is the carrier frequency  
fm is the modulating frequency (approx. 0.008*fc)  
d is the modulation ratio (approx 0.1)  
Dƒc  
d =  
ƒc  
(2)  
The maximum switching frequency fc is limited by the process and finally the parameter modulation ratio (d),  
together with fm , which is the side-band harmonics bandwidth around the carrier frequency fc . The bandwidth of  
a frequency modulated waveform is approximately given by the Carson’s rule and can be summarized as:  
B = 2 ´ ¦m ´ 1 + m = 2 ´ D¦ + ¦m  
(
)
(
)
¦
c
(3)  
fm < RBW: The receiver is not able to distinguish individual side-band harmonics, so, several harmonics are  
added in the input filter and the measured value is higher than expected in theoretical calculations.  
fm > RBW: The receiver is able to properly measure each individual side-band harmonic separately, so the  
measurements match with the theoretical calculations.  
ENABLE  
The TPS6267x device starts operation when EN is set high and starts up with the soft start as previously  
described. For proper operation, the EN pin must be terminated and must not be left floating.  
Pulling the EN pin low forces the device into shutdown, with a shutdown quiescent current of typically 0.1mA. In  
this mode, the P and N-channel MOSFETs are turned off, the internal resistor feedback divider is disconnected,  
and the entire internal-control circuitry is switched off. The TPS6267x device can actively discharge the output  
capacitor when it turns off. The integrated discharge resistor has a typical resistance of 100 . The required time  
to discharge the output capacitor at the output node depends on load current and the output capacitance value.  
When an external clock signal (EXTCLK), 4MHz to 27MHz is applied to the TPS62674, the DC/DC converter  
powers-up automatically within approx. 120ms. When the external clock signal is stopped, the DC/DC converter is  
powered down and the output capacitor is discharged actively.  
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SOFT START  
The TPS6267x has an internal soft-start circuit that limits the inrush current during start-up. This limits input  
voltage drops when a battery or a high-impedance power source is connected to the input of the converter.  
The soft-start system progressively increases the on-time from a minimum pulse-width of 35ns as a function of  
the output voltage. This mode of operation continues for c.a. 100ms after enable. Should the output voltage not  
have reached its target value by this time, such as in the case of heavy load, the soft-start transitions to a second  
mode of operation.  
The converter then operates in a current limit mode, specifically the P-MOS current limit is set to half the nominal  
limit, and the N-channel MOSFET remains on until the inductor current has reset. After a further 100 ms, the  
device ramps up to the full current limit operation if the output voltage has risen above 0.5V (approximately).  
Therefore, the start-up time mainly depends on the output capacitor and load current.  
UNDERVOLTAGE LOCKOUT  
The undervoltage lockout circuit prevents the device from misoperation at low input voltages. It prevents the  
converter from turning on the switch or rectifier MOSFET under undefined conditions. The TPS6267x device  
have a UVLO threshold set to 2.05V (typical). Fully functional operation is permitted down to 2.1V input voltage.  
SHORT-CIRCUIT PROTECTION  
The TPS6267x integrates a P-channel MOSFET current limit to protect the device against heavy load or short  
circuits. When the current in the P-channel MOSFET reaches its current limit, the P-channel MOSFET is turned  
off and the N-channel MOSFET is turned on. The regulator continues to limit the current on a cycle-by-cycle  
basis.  
As soon as the output voltage falls below ca. 0.4V, the converter current limit is reduced to half of the nominal  
value. Because the short-circuit protection is enabled during start-up, the device does not deliver more than half  
of its nominal current limit until the output voltage exceeds approximately 0.5V. This needs to be considered  
when a load acting as a current sink is connected to the output of the converter.  
THERMAL SHUTDOWN  
As soon as the junction temperature, TJ, exceeds typically 140°C, the device goes into thermal shutdown. In this  
mode, the P- and N-channel MOSFETs are turned off. The device continues its operation when the junction  
temperature again falls below typically 130°C.  
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APPLICATION INFORMATION  
INDUCTOR SELECTION  
The TPS6267x series of step-down converters have been optimized to operate with an effective inductance  
value in the range of 0.3mH to 1.8mH and with output capacitors in the range of 2.2mF to 4.7mF. The internal  
compensation is optimized to operate with an output filter of L = 0.47mH and CO = 2.2mF. Larger or smaller  
inductor values can be used to optimize the performance of the device for specific operation conditions. For more  
details, see the CHECKING LOOP STABILITY section.  
The inductor value affects its peak-to-peak ripple current, the PWM-to-PFM transition point, the output voltage  
ripple and the efficiency. The selected inductor has to be rated for its dc resistance and saturation current. The  
inductor ripple current (ΔIL) decreases with higher inductance and increases with higher VI or VO.  
V
V * V  
DI  
O
I
O
L
DI +  
 
DI  
+ I  
)
L
L(MAX)  
O(MAX)  
2
V
L   ƒ  
sw  
I
with: fSW = switching frequency (6 MHz typical)  
L = inductor value  
ΔIL = peak-to-peak inductor ripple current  
IL(MAX) = maximum inductor current  
(4)  
In high-frequency converter applications, the efficiency is essentially affected by the inductor AC resistance (i.e.  
quality factor) and to a smaller extent by the inductor DCR value. To achieve high efficiency operation, care  
should be taken in selecting inductors featuring a quality factor above 25 at the switching frequency. Increasing  
the inductor value produces lower RMS currents, but degrades transient response. For a given physical inductor  
size, increased inductance usually results in an inductor with lower saturation current.  
The total losses of the coil consist of both the losses in the DC resistance (DC)) and the following  
frequency-dependent components:  
The losses in the core material (magnetic hysteresis loss, especially at high switching frequencies)  
Additional losses in the conductor from the skin effect (current displacement at high frequencies)  
Magnetic field losses of the neighboring windings (proximity effect)  
Radiation losses  
The following inductor series from different suppliers have been used with the TPS6267x converters.  
Table 1. List of Inductors  
MANUFACTURER  
SERIES  
DIMENSIONS (in mm)  
2.0 x 1.2 x 1.0 max. height  
2.0 x 1.2 x 0.55 max. height  
2.0 x 1.2 x 0.55 max. height  
1.6 x 0.8 x 0.4 max. height  
1.6 x 0.8 x 0.33 max. height  
2.0 x 1.2 x 1.0 max. height  
2.0 x 1.2 x 1.0 max. height  
1.6 x 0.8 x 0.9 max. height  
1.6 x 0.8 x 0.9 max. height  
1.6 x 0.8 x 0.55 max. height  
1.6 x 0.8 x 0.4 max. height  
2.0 x 1.2 x 0.6 max. height  
2.0 x 1.2 x 1.0 max. height  
LQM21PN1R0NGR  
LQM21PNR47MC0  
LQM21PN1R0MC0  
LQM18PN1R5-B35  
LQM18PN1R5-A62  
ELGTEAR82NA  
CIG21L1R0MNE  
BRC1608T1R0  
MURATA  
PANASONIC  
SEMCO  
BRC1608T1R5  
TAIYO YUDEN  
CKP1608L1R5M  
CKP1608U1R5M  
MLP2012SR82T  
MDT2012-CR1R0A  
TDK  
TOKO  
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OUTPUT CAPACITOR SELECTION  
The advanced fast-response voltage mode control scheme of the TPS6267x allows the use of tiny ceramic  
capacitors. Ceramic capacitors with low ESR values have the lowest output voltage ripple and are  
recommended. For best performance, the device should be operated with a minimum effective output  
capacitance of 0.8mF. The output capacitor requires either an X7R or X5R dielectric. Y5V and Z5U dielectric  
capacitors, aside from their wide variation in capacitance over temperature, become resistive at high frequencies.  
At nominal load current, the device operates in PWM mode and the overall output voltage ripple is the sum of the  
voltage step caused by the output capacitor ESL and the ripple current flowing through the output capacitor  
impedance.  
At light loads, the output capacitor limits the output ripple voltage and provides holdup during large load  
transitions. A 2.2mF capacitor typically provides sufficient bulk capacitance to stabilize the output during large  
load transitions. The typical output voltage ripple is 1% of the nominal output voltage VO.  
The output voltage ripple during PFM mode operation can be kept very small. The PFM pulse is time controlled,  
which allows to modify the charge transferred to the output capacitor by the value of the inductor. The resulting  
PFM output voltage ripple and PFM frequency depend in first order on the size of the output capacitor and the  
inductor value. The PFM frequency decreases with smaller inductor values and increases with larger once.  
Increasing the output capacitor value and the effective inductance will minimize the output ripple voltage.  
INPUT CAPACITOR SELECTION  
Because of the nature of the buck converter having a pulsating input current, a low ESR input capacitor is  
required to prevent large voltage transients that can cause misbehavior of the device or interferences with other  
circuits in the system. For most applications, a 1 or 2.2-mF capacitor is sufficient. If the application exhibits a  
noisy or erratic switching frequency, the remedy will probably be found by experimenting with the value of the  
input capacitor.  
Take care when using only ceramic input capacitors. When a ceramic capacitor is used at the input and the  
power is being supplied through long wires, such as from a wall adapter, a load step at the output can induce  
ringing at the VIN pin. This ringing can couple to the output and be mistaken as loop instability or could even  
damage the part. Additional "bulk" capacitance (electrolytic or tantalum) should in this circumstance be placed  
between CI and the power source lead to reduce ringing than can occur between the inductance of the power  
source leads and CI.  
CHECKING LOOP STABILITY  
The first step of circuit and stability evaluation is to look from a steady-state perspective at the following signals:  
Switching node, SW  
Inductor current, IL  
Output ripple voltage, VO(AC)  
These are the basic signals that need to be measured when evaluating a switching converter. When the  
switching waveform shows large duty cycle jitter or the output voltage or inductor current shows oscillations, the  
regulation loop may be unstable. This is often a result of board layout and/or L-C combination.  
As a next step in the evaluation of the regulation loop, the load transient response is tested. The time between  
the application of the load transient and the turn on of the P-channel MOSFET, the output capacitor must supply  
all of the current required by the load. VO immediately shifts by an amount equal to ΔI(LOAD) x ESR, where ESR  
is the effective series resistance of CO. ΔI(LOAD) begins to charge or discharge CO generating a feedback error  
signal used by the regulator to return VO to its steady-state value. The results are most easily interpreted when  
the device operates in PWM mode.  
During this recovery time, VO can be monitored for settling time, overshoot or ringing that helps judge the  
converter’s stability. Without any ringing, the loop has usually more than 45° of phase margin.  
Because the damping factor of the circuitry is directly related to several resistive parameters (e.g., MOSFET  
rDS(on)) that are temperature dependant, the loop stability analysis has to be done over the input voltage range,  
load current range, and temperature range.  
22  
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TPS6267x  
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SLVS952 APRIL 2010  
LAYOUT CONSIDERATIONS  
As for all switching power supplies, the layout is an important step in the design. High-speed operation of the  
TPS6267x devices demand careful attention to PCB layout. Care must be taken in board layout to get the  
specified performance. If the layout is not carefully done, the regulator could show poor line and/or load  
regulation, stability and switching frequency issues as well as EMI problems. It is critical to provide a low  
inductance, impedance ground path. Therefore, use wide and short traces for the main current paths.  
The input capacitor should be placed as close as possible to the IC pins as well as the inductor and output  
capacitor. In order to get an optimum ESL step, the output voltage feedback point (FB) should be taken in the  
output capacitor path, approximately 1mm away for it. The feed-back line should be routed away from noisy  
components and traces (e.g. SW line).  
MODE  
VIN  
CI  
L
ENABLE  
CO  
GND  
VOUT  
Figure 42. Suggested Layout (Top)  
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TPS6267x  
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THERMAL INFORMATION  
Implementation of integrated circuits in low-profile and fine-pitch surface-mount packages typically requires  
special attention to power dissipation. Many system-dependant issues such as thermal coupling, airflow, added  
heat sinks, and convection surfaces, and the presence of other heat-generating components, affect the  
power-dissipation limits of a given component.  
Three basic approaches for enhancing thermal performance are listed below:  
Improving the power dissipation capability of the PCB design  
Improving the thermal coupling of the component to the PCB  
Introducing airflow into the system  
The maximum recommended junction temperature (TJ) of the TPS6267x devices is 105°C. The thermal  
resistance of the 6-pin CSP package (YFD-6) is RqJA = 125°C/W. Regulator operation is specified to a maximum  
steady-state ambient temperature TA of 85°C. Therefore, the maximum power dissipation is about 160 mW.  
T
- T  
A
105°C - 85°C  
125°C/W  
J(MAX)  
P
=
=
= 160mW  
D(MAX)  
R
qJA  
(5)  
PACKAGE SUMMARY  
CHIP SCALE PACKAGE  
(BOTTOM VIEW)  
CHIP SCALE PACKAGE  
(TOP VIEW)  
A2  
B2  
C2  
A1  
B1  
C1  
YMSCC  
LLLL  
D
A1  
Code:  
YM — Year Month date Code  
S — Assembly site code  
CC— Chip code  
E
LLLL — Lot trace code  
CHIP SCALE PACKAGE DIMENSIONS  
The TPS6267x device is available in an 6-bump chip scale package (YFD, NanoFree™). The package  
dimensions are given as:  
D = 1.30 ±0.03 mm  
E = 0.926 ±0.03 mm  
24  
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Product Folder Link(s): TPS6267x  
TPS6267x  
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SLVS952 APRIL 2010  
APPLICATION INFORMATION  
V
V
OUT  
1.26 V @ 500 mA  
TPS62674  
L
BAT  
2.3 V .. 4.8 V  
VIN  
SW  
1.5 mH  
C
O
C
I
MODE  
FB  
2.2 mF  
1 mF  
L = muRata LQM18PN1R5-B35  
CI = muRata GRM153R60J105M  
EN  
GND  
EXTCLK  
CO = muRata GRM153R60G225M  
Figure 43. 1.26V CMOS Sensor Embedded Power Solution — Featuring Sub 0.4mm Profile  
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PACKAGE OPTION ADDENDUM  
www.ti.com  
7-May-2010  
PACKAGING INFORMATION  
Orderable Device  
Status (1)  
Package Package  
Pins Package Eco Plan (2) Lead/Ball Finish MSL Peak Temp (3)  
Qty  
Type  
Drawing  
TPS62674YFDR  
TPS62674YFDT  
ACTIVE  
ACTIVE  
DSBGA  
DSBGA  
YFD  
6
6
3000  
250  
TBD  
TBD  
Call TI  
Call TI  
Call TI  
Call TI  
YFD  
(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.  
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Addendum-Page 1  
X: Max = 1350 µm, Min = 1250 µm  
Y: Max = 976 µm, Min = 876 µm  
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