TPS70845PWPR [TI]
DUAL OUTPUT, FIXED POSITIVE LDO REGULATOR, PDSO20, GREEN, PLASTIC, HTSSOP-20;型号: | TPS70845PWPR |
厂家: | TEXAS INSTRUMENTS |
描述: | DUAL OUTPUT, FIXED POSITIVE LDO REGULATOR, PDSO20, GREEN, PLASTIC, HTSSOP-20 光电二极管 输出元件 调节器 |
文件: | 总37页 (文件大小:874K) |
中文: | 中文翻译 | 下载: | 下载PDF数据表文档文件 |
TPS70845, TPS70848
TPS70851, TPS70858
TPS70802
www.ti.com
SLVS301D–JUNE 2000–REVISED DECEMBER 2007
DUAL-OUTPUT, LOW DROPOUT VOLTAGE REGULATORS
WITH INTEGRATED SVS FOR SPLIT VOLTAGE SYSTEMS
1
FEATURES
DESCRIPTION
23
•
Dual Output Voltages for Split-Supply
The TPS708xx is a low dropout voltage regulator with
integrated SVS (RESET, POR, or power on reset)
and power good (PG) functions. These devices are
capable of supplying 250 mA and 125 mA by
regulator 1 and regulator 2 respectively. Quiescent
current is typically 190 µA at full load. Differentiated
features, such as accuracy, fast transient response,
SVS supervisory circuit (power on reset), manual
reset input, and independent enable functions provide
a complete system solution.
Applications
•
•
•
Independent Enable Functions (See Part
Number TPS707xx for Sequenced Outputs)
Output Current Range of 250 mA on Regulator
1 and 125 mA on Regulator 2
Voltage Options: 3.3-V/2.5-V, 3.3-V/1.8-V,
3.3-V/1.5-V, 3.3-V/1.2-V, and Dual Adjustable
Outputs
•
•
Open Drain Power-On Reset with 120-ms Delay
PWP PACKAGE
(TOP VIEW)
Open Drain Power Good for Regulator 1 and
Regulator 2
NC
1
20
19
18
17
16
15
14
13
12
11
NC
V
•
•
•
Ultralow 190-µA (typ) Quiescent Current
1-µA Input Current During Standby
V
2
IN1
IN1
OUT1
V
V
V
3
OUT1
/FB1
/FB2
4
MR
SENSE1
Low Noise: 65 µVRMS Without Bypass
Capacitor
5
PG1
EN1
EN2
6
PG2
V
•
•
•
•
•
•
Quick Output Capacitor Discharge Feature
One Manual Reset Input
7
RESET
GND
SENSE2
V
V
8
OUT2
V
9
OUT2
IN2
2% Accuracy Over Load and Temperature
Undervoltage Lockout (UVLO) Feature
20-Pin PowerPAD™ TSSOP Package
Thermal Shutdown Protection
V
10
NC
IN2
NC: No internal connection
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
PowerPAD is a trademark of Texas Instruments.
All other 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 © 2000–2007, Texas Instruments Incorporated
TPS70845, TPS70848
TPS70851, TPS70858
TPS70802
www.ti.com
SLVS301D–JUNE 2000–REVISED DECEMBER 2007
TPS70851PWP
I/O
3.3 V
V
V
OUT1
5V
IN1
10 mF
0.1 mF
V
SENSE1
250 kW
PG1
250 kW
250 kW
PG1
MR
MR
>2 V
V
IN2
<0.7 V
0.1 mF
RESET
PG2
RESET
PG2
EN1
>2 V
>2 V
EN1
EN2
<0.7 V
<0.7 V
EN2
V
SENSE2
1.8 V
V
Core
OUT2
10 mF
DESCRIPTION (CONTINUED)
The TPS708xx family of voltage regulators offers very low dropout voltage and dual outputs. These devices have
extremely low noise output performance without using any added filter bypass capacitors and are designed to
have a fast transient response and be stable with 10-µF low ESR capacitors.
These devices have fixed 3.3-V/2.5-V, 3.3-V/1.8-V, 3.3-V/1.5-V, 3.3-V/1.2-V, and adjustable voltage options.
Regulator 1 can support up to 250 mA, and regulator 2 can support up to 125 mA. Separate voltage inputs allow
the designer to configure the source power.
Because the PMOS device behaves as a low-value resistor, the dropout voltage is very low (typically 170 mV on
regulator 1) and is directly proportional to the output current. Additionally, since the PMOS pass element is a
voltage-driven device, the quiescent current is very low and independent of output loading (maximum of 230 µA
over the full range of output current and full range of temperature). This LDO family also features a sleep mode;
applying a high signal to EN1 or EN2 (enable) shuts down regulator 1 or regulator 2, respectively. When a high
signal is applied to both EN1 and EN2, both regulators enter sleep mode, thereby reducing the input current to 2
µA at TJ = +25°C.
For each regulator, there is an internal discharge transistor to discharge the output capacitor when the regulator
is turned off (disabled).
The PG1 pin reports the voltage condition at VOUT1. The PG1 pin can be used to implement a SVS (RESET,
POR, or power on reset) for the circuitry supplied by regulator 1. The PG2 pin reports the voltage conditions at
VOUT2. The PG2 pin can be used to implement a SVS (power on reset) for the circuitry supplied by regulator 2.
The TPS708xx features a RESET (SVS, POR, or power on reset). RESET output initiates a reset in the event of
an undervoltage condition. RESET also indicates the status of the manual reset pin (MR). When MR is in the
logic high state, RESET goes to a high impedance state after a 120-ms delay. To monitor VOUT1, the PG1 output
pin can be connected to MR. To monitor VOUT2, the PG2 output pin can be connected to MR.
The device has an undervoltage lockout UVLO circuit that prevents the internal regulators from turning on until
VIN1 reaches 2.5V.
2
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Copyright © 2000–2007, Texas Instruments Incorporated
TPS70845, TPS70848
TPS70851, TPS70858
TPS70802
www.ti.com
SLVS301D–JUNE 2000–REVISED DECEMBER 2007
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)
VOLTAGE (V)(2)
PACKAGE-
LEAD
(DESIGNATOR)
SPECIFIED
TEMPERATURE
RANGE (TJ)
ORDERING
NUMBER
TRANSPORT
MEDIA, QUANTITY
PRODUCT
VOUT1
VOUT2
TPS70802PWP
TPS70802PWPR
TPS70845PWP
TPS70845PWPR
TPS70848PWP
TPS70848PWPR
TPS70851PWP
TPS70851PWPR
TPS70858PWP
TPS70858PWPR
Tube, 70
Tape and Reel, 2000
Tube, 70
TPS70802
Adjustable
Adjustable HTSSOP-20 (PWP)
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
–40°C to +125°C
TPS70845
TPS70848
TPS70851
TPS70858
3.3 V
3.3 V
3.3 V
3.3 V
1.2 V
1.5 V
1.8 V
2.5 V
HTSSOP-20 (PWP)
HTSSOP-20 (PWP)
HTSSOP-20 (PWP)
HTSSOP-20 (PWP)
Tape and Reel, 2000
Tube, 70
Tape and Reel, 2000
Tube, 70
Tape and Reel, 2000
Tube, 70
Tape and Reel, 2000
(1) For the most current package and ordering information see the Package Option Addendum located at the end of this document, or see
the TI web site at www.ti.com.
(2) For fixed 1.20 V operation, tie FB to OUT.
ABSOLUTE MAXIMUM RATINGS(1)
Over operating free-air temperature range (unless otherwise noted).
TPS708xx
UNIT
V
(2)
Input voltage range: VIN1, VIN2
Voltage range at EN1, EN2
–0.3 to +7
–0.3 to +7
V
Output voltage range (VOUT1, VSENSE1
Output voltage range (VOUT2, VSENSE2
Maximum RESET, PG1, PG2 voltage
Maximum MR voltage
)
5.5
V
)
5.5
V
7
V
VIN1
Internally limited
See Dissipation Ratings Table
–40 to +150
V
Peak output current
—
—
°C
°C
kV
Continuous total power dissipation
Operating virtual junction temperature range, TJ
Storage temperature range, Tstg
ESD rating, HBM
–65 to +150
2
(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) All voltages are tied to network ground.
Copyright © 2000–2007, Texas Instruments Incorporated
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TPS70851, TPS70858
TPS70802
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SLVS301D–JUNE 2000–REVISED DECEMBER 2007
DISSIPATION RATINGS
DERATING
FACTOR
PACKAGE
AIR FLOW (CFM)
TA ≤ +25°C
TA = +70°C
TA = +85°C
0
3.067 W
4.115 W
30.67 mW/°C
41.15 mW/°C
1.687 W
2.265 W
1.227 W
1.646 W
PWP(1)
250
(1) This parameter is measured with the recommended copper heat sink pattern on a 4-layer PCB, 1 oz. copper on a 4-in by 4-in ground
layer. Simultaneous and continuous operation of both regulator outputs at full load may exceed the power dissipation rating of the PWP
package. For more information, refer to TI technical brief SLMA002.
RECOMMENDED OPERATING CONDITIONS
Over operating temperature range (unless otherwise noted).
MIN
2.7
0
MAX
6
UNIT
V
Input voltage, VI(1) (regulator 1 and 2)
Output current, IO (regulator 1)
500
250
5.5
mA
mA
V
Output current, IO (regulator 2)
0
Output voltage range (for adjustable option)
Operating virtual junction temperature, TJ
1.22
–40
+125
°C
(1) To calculate the minimum input voltage for maximum output current, use the following equation: VI(min) = VO(max) + VDO(max load)
.
4
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TPS70845, TPS70848
TPS70851, TPS70858
TPS70802
www.ti.com
SLVS301D–JUNE 2000–REVISED DECEMBER 2007
ELECTRICAL CHARACTERISTICS
Over recommended operating junction temperature range (TJ = –40°C to +125°C), VIN1 or VIN2 = VOUT(nom) + 1 V, IO = 1 mA,
EN = 0 V, and COUT = 33 µF (unless otherwise noted).
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX UNIT
2.7 V < VIN < 6 V,
TJ = +25°C
FB connected to VO
1.22
Reference
voltage
2.7 V < VIN < 6 V,
2.7 V < VIN < 6 V,
2.7 V < VIN < 6 V,
2.7 V < VIN < 6 V,
2.7 V < VIN < 6 V,
2.8 V < VIN < 6 V,
2.8 V < VIN < 6 V,
3.5 V < VIN < 6 V,
3.5 V < VIN < 6 V,
4.3 V < VIN < 6 V,
4.3 V < VIN < 6 V,
FB connected to VO
1.196
1.176
1.47
1.244
1.224
TJ = +25°C
1.2
1.5
1.8
2.5
3.3
190
1.2 V Output
1.5 V Output
1.8 V Output
2.5 V Output
3.3 V Output
TJ = +25°C
TJ = +25°C
TJ = +25°C
TJ = +25°C
TJ = +25°C
Output
voltage
1.53
1.836
2.55
VO
V
(1),(2)
1.764
2.45
3.234
3.366
(2)
Quiescent current (GND current) for
regulator 1 and regulator 2, EN1 = EN2
= 0 V(1)
See
µA
(2)
See
230
0.1
VO + 1 V < VIN ≤ 6 V,
VO + 1 V < VIN ≤ 6 V
TJ = +25°C
TJ = +25°C(1)
(1)
0.01
Output voltage line regulation (∆VO/VO)
for regulator 1 and regulator 2
%V
mV
(3)
Load regulation for VOUT 1 and VOUT2
1
65
Regulator 1
Regulator 2
Regulator 1
Regulator 2
Output noise
voltage
Vn
BW = 300 Hz to 50 kHz,
VOUT = 0 V
CO = 33 µF, TJ = +25°C
µVRMS
65
1.6
1.9
1
Output current limit
A
0.750
+150
Thermal shutdown junction temperature
°C
µA
Regulator 1
Regulator 2
EN1 = VIN, EN2 = VIN
EN1 = VIN, EN2 = VIN
TJ = +25°C
2
6
II
Standby
(standby) current
f = 1 kHz, COUT = 33 µF,
IOUT1 = 250 mA
Regulator 1
Regulator 2
TJ = +25°C(1)
TJ = +25°C(1)
60
50
Power-
supply ripple
rejection
PSRR
dB
V
f = 1 kHz, COUT = 33 µF,
IOUT2 = 125 mA
UVLO threshold
2.4
80
2.65
RESET Terminal
Minimum input voltage for valid RESET I(RESET) = 300 µA,
V
(RESET) ≤ 0.8 V
1.0
120
1.3
160
0.4
1
V
ms
V
t(RESET)
RESET pulse duration
VIN = 3.5 V,
Output low voltage
Leakage current
I(RESET) = 1 mA
0.15
V(RESET) = 6 V
µA
(1) Minimum input operating voltage is 2.7 V or VO(typ) + 1 V, whichever is greater. Maximum input voltage = 6 V, minimum output
current = 1 mA.
(2) IO = 1 mA to 250 mA for Regulator 1 and 1 mA to 125 mA for Regulator 2.
(VImax - 2.7)
Line regulation (mV) = (%/V) x Vo
x 1000
100
[VImax - (Vo + 1)]
(3) If VO < 1.8 V then VImax = 6 V, VImin = 2.7 V:
Line regulation (mV) = (%/V) x Vo
x 1000
100
If VO > 2.5 V then VImax = 6 V, VImin = VO + 1 V:
Copyright © 2000–2007, Texas Instruments Incorporated
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TPS70851, TPS70858
TPS70802
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SLVS301D–JUNE 2000–REVISED DECEMBER 2007
ELECTRICAL CHARACTERISTICS (continued)
Over recommended operating junction temperature range (TJ = –40°C to +125°C), VIN1 or VIN2 = VOUT(nom) + 1 V, IO = 1 mA,
EN = 0 V, and COUT = 33 µF (unless otherwise noted).
PARAMETER
PG1/PG2 Terminal
TEST CONDITIONS
MIN
TYP
MAX UNIT
Minimum input voltage for valid PGx
Trip threshold voltage
Hysteresis voltage
I(PGx) = 300 µA,
VO decreasing
Measured at VO
Rising edge deglitch
VIN = 2.7V,
V
(PGx) ≤ 0.8 V
1.0
95
1.3
V
92
98 %VOUT
%VOUT
µs
0.5
30
tr(PGx)
Output low voltage
Leakage current
I(PGx) = 1 mA
0.15
0.4
1
V
V(PGx) = 6V
µA
EN1/EN2 Terminal
High-level ENx input voltage
Low-level ENx input voltage
Input current (ENx)
MR Terminal
2
–1
2
V
V
0.7
1
µA
High-level input voltage
Low-level input voltage
Falling edge delay
V
V
0.7
Measured at VO
140
6
µs
µA
Pull-up current source
VOUT1 Terminal
IO = 250 mA, VIN1 = 3.2 V
IO = 250 mA, VIN1 = 3.2 V
2 ms pulse width
TJ = +25°C
83
Dropout voltage(4)
mV
140
Peak output current
Discharge transistor current
VOUT2 Terminal
750
7.5
mA
mA
VOUT1 = 1.5 V
Peak output current
Discharge transistor current
FB Terminal
2 ms pulse width
VOUT2 = 1.5 V
375
7.5
mA
mA
Input current: TPS70802
FB = 1.8 V
1
µA
(4) Input voltage (VIN1 or VIN2) = VO(typ) – 100 mV. For 1.5-V, 1.8-V, and 2.5-V regulators, the dropout voltage is limited by input voltage
range. The 3.3-V regulator input is set to 3.2 V to perform this test.
6
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TPS70845, TPS70848
TPS70851, TPS70858
TPS70802
www.ti.com
SLVS301D–JUNE 2000–REVISED DECEMBER 2007
DEVICE INFORMATION
Fixed Voltage Version
V
(2 Pins)
IN1
V
V
(2 Pins)
OUT1
UVLO
Comp
10 kW
Current
Sense
-
ENA_1
SENSE1
+
2.5 V
(see Note A)
-
+
ENA_1
Reference
V
ref
FB1
GND
Thermal
V
ref
Shutdown
PG1
-
V
SENSE1
Rising Edge
Deglitch
+
0.95 x Vref
V
IN1
PG1
Comp
MR
RESET
Falling Edge
Delay
ENA_1
EN1
PG2
PG2
Comp
-
V
SENSE2
Rising Edge
Deglitch
0.95 x V
ref
+
ENA_2
V
ref
FB2
EN2
-
+
ENA_2
V
SENSE2
Current
Sense
ENA_2
(see Note A)
10 kW
V
(2 Pins)
OUT2
V
(2 Pins)
IN2
A. For most applications, VSENSE1 and VSENSE2 should be externally connected to VOUT1 and VOUT2, respectively, as
close as possible to the device. For other implementations, refer to SENSE terminal connection discussion in the
Application Information section.
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TPS70851, TPS70858
TPS70802
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SLVS301D–JUNE 2000–REVISED DECEMBER 2007
Adjustable Voltage Version
V
(2 Pins)
IN1
V
(2 Pins)
OUT1
UVLO
Comp
Current
Sense
-
FB1
ENA_1
+
2.5 V
(see Note A)
-
+
ENA_1
Reference
V
ref
GND
Thermal
V
ref
Shutdown
PG1
-
FB1
0.95 x V
Rising Edge
Deglitch
+
V
ref
IN1
PG1
Comp
MR
RESET
Falling Edge
Delay
ENA_1
EN1
PG2
PG2
Comp
-
FB2
0.95 x V
Rising Edge
Deglitch
+
ref
ENA_2
V
ref
FB2
EN2
-
+
ENA_2
FB2
Current
Sense
ENA_2
(see Note A)
V (2 Pins)
OUT2
V
(2 Pins)
IN2
A. For most applications, FB1 and FB2 should be externally connected to resistor dividers as close as possible to the
device. For other implementations, refer to FB terminals connection discussion in the Application Information
section.
8
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Copyright © 2000–2007, Texas Instruments Incorporated
TPS70845, TPS70848
TPS70851, TPS70858
TPS70802
www.ti.com
SLVS301D–JUNE 2000–REVISED DECEMBER 2007
RESET Timing Diagram
V
IN1
V
UVLO
V
UVLO
V
V
RES
RES
(see Note A)
t
MR Input
t
RESET Output
120 ms
Delay
120 ms
Delay
Output
Output
Undefined
Undefined
t
NOTE A: VRES is the minimum input voltage for a valid RESET. The symbol VRES is not currently listed within EIA or JEDEC
standards for semiconductor symbology.
PG1 Timing Diagram
V
IN1
V
UVLO
V
UVLO
V
PG1
V
PG
(see Note A)
t
V
OUT1
V
IT+
(see Note B)
Threshold
Voltage
V
IT-
(see Note B)
t
PG1 Output
Output
PG1
Output
Undefined
Undefined
t
NOTES A: VPG1 is the minimum input voltage for a valid PG. The symbol VPG1 is not currently listed within EIA or JEDEC
standards for semiconductor symbology.
NOTES B: VIT- trip voltage is typically 5% lower than the output voltage (95%VO). VIT- to VIT+ is the hysteresis voltage.
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SLVS301D–JUNE 2000–REVISED DECEMBER 2007
PG2 Timing Diagram (assuming VIN1 already powered up)
V
IN2
t
V
OUT2
V
IT+
(see Note A)
Threshold
Voltage
V
IT-
(see Note A)
t
PG2
Output
t
NOTE A: VIT- trip voltage is typically 5% lower than the output voltage (95%VO). VIT- to VIT+ is the hysteresis voltage.
TERMINAL FUNCTIONS
TERMINAL
I/O
DESCRIPTION
NAME
EN1
NO.
5
6
I
I
Active low enable for VOUT1
EN2
Active low enable for VOUT2
GND
8
—
I
Ground
MR
4
Manual reset input, active low, pulled up internally
No connection
NC
1, 11, 20
16
—
O
O
I
PG1
Open drain output, low when VOUT1 voltage is less than 95% of the nominal regulated voltage
Open drain output, low when VOUT2 voltage is less than 95% of the nominal regulated voltage
Open drain output, SVS (power-on reset) signal, active low
Input voltage of regulator 1
PG2
15
RESET
VIN1
7
2, 3
9, 10
18, 19
12, 13
14
I
VIN2
I
Input voltage of regulator 2
VOUT1
VOUT2
VSENSE2/FB2
VSENSE1/FB1
O
O
I
Output voltage of regulator 1
Output voltage of regulator 2
Regulator 2 output voltage sense/regulator 2 feedback for adjustable
Regulator 1 output voltage sense/regulator 1 feedback for adjustable
17
I
10
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TPS70845, TPS70848
TPS70851, TPS70858
TPS70802
www.ti.com
SLVS301D–JUNE 2000–REVISED DECEMBER 2007
Detailed Description
The TPS708xx low dropout regulator family provides dual regulated output voltages with independent enable
functions. These devices provide fast transient response and high accuracy with small output capacitors, while
drawing low quiescent current. Other features are integrated SVS (power-on reset, RESET) and power good
(PG1, PG2) that monitor output voltages and provide logic output to the system. These differentiated features
provide a complete power solution.
The TPS708xx, unlike many other LDOs, features very low quiescent current that remains virtually constant even
with varying loads. Conventional LDO regulators use a PNP pass element, the base current of which is directly
proportional to the load current through the regulator (IB = IC/β). The TPS708xx uses a PMOS transistor to pass
current; because the gate of the PMOS is voltage-driven, operating current is low and stable over the full load
range.
Pin Functions
Enable (EN1, EN2)
The EN terminals are inputs that enable or shut down each respective regulator. If EN is at a voltage high signal,
the respective regulator is in shutdown mode. When EN goes to voltage low, the respective regulator is enabled.
Power-Good (PG1, PG2)
The PG terminals are open drain, active high output terminals that indicate the status of each respective
regulator. When VOUT1 reaches 95% of its regulated voltage, PG1 goes to a high impedance state. When VOUT2
reaches 95% of its regulated voltage, PG2 goes to a high impedance state. Each PG goes to a low impedance
state when its respective output voltage is pulled below 95% (that is, goes to an overload condition) of its
regulated voltage. The open drain outputs of the PG terminals require a pull-up resistor.
Manual Reset Pin
MR is an active low input terminal used to trigger a reset condition. When MR is pulled to logic low, a POR
(RESET) occurs. The terminal has a 6-µA pull-up current to VIN1
.
Sense (VSENSE1, VSENSE2
)
The sense terminals of fixed-output options must be connected to the regulator outputs, and the connection
should be as short as possible. Internally, the sense terminal connects to high-impedance, wide-bandwidth
amplifiers through a resistor-divider network and noise pickup feeds through to the regulator output. It is essential
to route the sense connection in such a way as to minimize or avoid noise pickup. Adding RC networks between
sense terminals and VOUT terminals to filter noise is not recommended because these networks can cause the
regulators to oscillate.
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SLVS301D–JUNE 2000–REVISED DECEMBER 2007
FB1 and FB2
FB1 and FB2 are input terminals used for adjustable-output devices and must be connected to the external
feedback resistor divider. FB1 and FB2 connections should be as short as possible. It is essential to route them
in such a way as to minimize or avoid noise pickup. Adding RC networks between FB terminals and VOUT
terminals to filter noise is not recommended because these networks can cause the regulators to oscillate.
RESET Indicator
The TPS708xx features a RESET (SVS, POR, or power on reset). RESET can be used to drive power on reset
circuitry or a low-battery indicator. RESET is an active low, open drain output that indicates the status of the
manual reset pin (MR). When MR is in a high-impedance state, RESET goes to a high impedance state after a
120-ms delay. To monitor VOUT1, the PG1 output pin can be connected to MR. To monitor VOUT2, the PG2 output
pin can be connected to MR. The open drain output of the RESET terminal requires a pull-up resistor. If RESET
is not used, it can be left floating.
VIN1 and VIN2
VIN1 and VIN2 are inputs to each regulator. Internal bias voltages are powered by VIN1
.
VOUT1 and VOUT2
VOUT1 and VOUT2 are output terminals of each regulator.
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SLVS301D–JUNE 2000–REVISED DECEMBER 2007
TYPICAL CHARACTERISTICS
Table of Graphs
FIGURE
vs Output current
vs Junction temperature
vs Junction temperature
vs Frequency
Figure 1 to Figure 3
Figure 4 to Figure 5
Figure 6
VO
Output voltage
Ground current
PSRR
ZO
Power-supply rejection ratio
Output spectral noise density
Output impedance
Figure 7 to Figure 10
Figure 11 to Figure 14
Figure 15 to Figure 18
Figure 19 and Figure 20
Figure 21 and Figure 22
Figure 23 and Figure 24
Figure 25
vs Frequency
vs Frequency
vs Temperature
vs Input voltage
Dropout voltage
Load transient response
Line transient response (VOUT1
Line transient response (VOUT2
Output voltage
)
)
Figure 26
VO
vs Time (start-up)
vs Output current
Figure 27 and Figure 28
Figure 30 to Figure 33
Equivalent series resistance (ESR)
TPS70851
OUTPUT VOLTAGE
vs
TPS70851
OUTPUT VOLTAGE
vs
OUTPUT CURRENT
OUTPUT CURRENT
3.303
3.302
3.301
3.3
1.802
1.801
1.800
1.799
1.798
1.797
V
T
= 4.3 V
IN1
V
T
= 2.8 V
IN2
= +25°C
J
= +25°C
J
V
OUT1
V
OUT2
3.299
3.298
3.297
1.796
1.795
3.296
3.295
0
0.05
0.1
0.15
0.2
0.25
0
0.025
0.05
0.075
0.1
0.125
I
- Output Current - A
I
- Output Current - A
O
O
Figure 1.
Figure 2.
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TPS70845
OUTPUT VOLTAGE
vs
TPS70851
OUTPUT VOLTAGE
vs
OUTPUT CURRENT
JUNCTION TEMPERATURE
1.201
1.200
3.35
3.33
V
V
= 4.3 V
V
T
= 2.7 V
IN1
IN2
= +25°C
OUT1
J
V
OUT2
I
O
= 250 mA
1.199
1.198
1.197
3.31
3.29
I
O
= 1 mA
3.27
3.25
3.23
1.196
1.195
-40 -25 -10
5
20 35 50 65 80 95 110 125
0
0.025
0.05
0.075
0.1
0.125
T
- Junction Temperature - °C
J
I
- Output Current - A
O
Figure 3.
Figure 4.
TPS70851
TPS70851
GROUND CURRENT
vs
OUTPUT VOLTAGE
vs
JUNCTION TEMPERATURE
JUNCTION TEMPERATURE
210
1.85
1.83
1.81
1.79
1.77
1.75
1.73
V
V
= 2.8 V
IN2
Regulator 1 and Regulator 2
OUT2
200
190
I
= 1 mA
OUT1
I
= 1 mA
I
O
= 1 mA
OUT2
180
170
I
O
= 250 mA
I
I
= 250 mA
= 125 mA
OUT1
OUT2
160
150
40 25 10
5
20 35 50 65 80 95 110 125
-40 -25 -10
5
20 35 50 65 80 95 110 125
T
- Junction Temperature - °C
T
- Junction Temperature - °C
J
J
Figure 5.
Figure 6.
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SLVS301D–JUNE 2000–REVISED DECEMBER 2007
TPS70851
TPS70851
POWER-SUPPLY REJECTION RATIO
POWER-SUPPLY REJECTION RATIO
vs
vs
FREQUENCY
FREQUENCY
10
0
-10
I = 250 mA
O
I
= 10 mA
O
C
V
= 22 mF
O
-20
-30
-40
C
= 22 mF
O
V
OUT1
-10
-20
OUT1
-30
-40
-50
-60
-70
-50
-60
-70
-80
-90
-80
-90
10
100
1 k
10 k
100 k
1 M
10
100
1 k
10 k
100 k
1 M
f - Frequency - Hz
f - Frequency - Hz
Figure 7.
Figure 8.
TPS70851
TPS70851
POWER-SUPPLY REJECTION RATIO
POWER-SUPPLY REJECTION RATIO
vs
vs
FREQUENCY
FREQUENCY
-10
-20
10
0
I
= 10 mA
O
I
= 150 mA
O
C
V
= 22 mF
O
C
V
= 22 mF
O
OUT2
-10
-20
OUT2
-30
-40
-30
-40
-50
-50
-60
-70
-60
-70
-80
-90
-80
-90
10
100
1 k
10 k
100 k
1 M
10
100
1 k
10 k
100 k
1 M
f - Frequency - Hz
f - Frequency - Hz
Figure 9.
Figure 10.
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OUTPUT SPECTRAL NOISE DENSITY
OUTPUT SPECTRAL NOISE DENSITY
vs
vs
FREQUENCY
FREQUENCY
10
10
V
V
I
= 4.3 V
V
V
I
= 4.3 V
IN1
IN1
= 3.3 V
= 250 mA
= 3.3 V
= 10 mA
OUT1
OUT1
O
O
1
1
0.1
0.1
0.01
0.01
100
100
1 k
10 k
100 k
1 k
10 k
100 k
f - Frequency - Hz
f - Frequency - Hz
Figure 11.
Figure 12.
OUTPUT SPECTRAL NOISE DENSITY
OUTPUT SPECTRAL NOISE DENSITY
vs
vs
FREQUENCY
FREQUENCY
10
10
V
V
I
= 2.8 V
V
V
I
= 2.8 V
IN2
IN2
= 1.8 V
= 1.8 V
OUT2
OUT2
= 125 mA
= 10 mA
O
O
1
1
0.1
0.1
0.01
100
0.01
100
1 k
10 k
100
1 k
10 k
100 k
f - Frequency - Hz
f - Frequency - Hz
Figure 13.
Figure 14.
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SLVS301D–JUNE 2000–REVISED DECEMBER 2007
OUTPUT IMPEDANCE
vs
OUTPUT IMPEDANCE
vs
FREQUENCY
FREQUENCY
100
10
C
C
I
= 33 mF
O
= 33 mF
O
= 10 mA
I
= 250 mA
O
O
V
T
= 3.3 V
V
T
= 3.3 V
OUT1
= +25°C
OUT1
= +25°C
J
10
1
J
1
0.1
0.1
0.01
0.01
10
100
1 k
10 k
100 k
1 M
10 M
10
100
1 k
10 k
100 k
1 M
10 M
f - Frequency - Hz
f - Frequency - Hz
Figure 15.
Figure 16.
OUTPUT IMPEDANCE
vs
OUTPUT IMPEDANCE
vs
FREQUENCY
FREQUENCY
10
100
C
= 33 mF
O
C
I
= 33 mF
O
I
= 10 mA
O
= 125 mA
O
V
T
= 1.8 V
OUT2
V
T
= 1.8 V
OUT2
= +25°C
= +25°C
J
10
1
J
1
0.1
0.01
0.1
10
100
1 k
10 k
100 k
1 M
10 M
10
100
1 k
10 k
100 k
1 M
10 M
f - Frequency - Hz
f - Frequency - Hz
Figure 17.
Figure 18.
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TPS70851
DROPOUT VOLTAGE
vs
TPS70851
DROPOUT VOLTAGE
vs
TEMPERATURE
TEMPERATURE
120
6
5
C
V
= 33 mF
C
V
= 33 mF
O
O
= 3.2 V
= 3.2 V
IN1
IN1
100
I
O
= 10 mA
I
O
= 250 mA
80
60
40
4
3
2
20
0
1
0
I
O
= 0 mA
-40 -25 -10
5
20 35 50 65 80 95 110 125
-40 -25 -10
5
20 35 50 65 80 95 110 125
T
- Junction Temperature - °C
T
- Junction Temperature - °C
J
J
Figure 19.
Figure 20.
TPS70802
DROPOUT VOLTAGE
vs
TPS70802
DROPOUT VOLTAGE
vs
INPUT VOLTAGE
INPUT VOLTAGE
140
250
I
= 250 mA
O
I
= 125 mA
O
V
OUT1
V
120
100
80
OUT2
T
= +125°C
200
J
T
= +125°C
J
T
J
= +25°C
J
150
100
T
= +25°C
J
60
T
= -40°C
40
T
= -40°C
J
50
0
20
0
2.5
3
3.5
4
4.5
5
2.5
3
3.5
4
4.5
5
V - Input Voltage - V
V - Input Voltage - V
I
I
Figure 21.
Figure 22.
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LOAD TRANSIENT RESPONSE
LOAD TRANSIENT RESPONSE
C
T
= 33 mF
C
T
= 33 mF
O
O
= +25°C
= +25°C
250
0
125
0
J
J
V
= 3.3 V
V
= 1.8 V
OUT1
OUT2
20
0
20
0
-20
-40
-20
-40
-60
-80
0
0.2 0.4 0.6 0.8
1
1.2 1.4 1.6 1.8
2
0
0.2 0.4 0.6 0.8
1
1.2 1.4 1.6 1.8
2
T - Time - ms
T - Time - ms
Figure 23.
Figure 24.
LINE TRANSIENT RESPONSE
LINE TRANSIENT RESPONSE
3.8
2.8
5.3
4.3
50
0
10
0
I
= 125 mA
I
= 250 mA
O
O
C
V
= 33 mF
C
V
= 33 mF
O
O
-50
-10
OUT2
OUT1
0
20 40 60 80 100 120 140 160 180 200
0
20 40 60 80 100 120 140 160 180 200
T - Time - ms
T - Time - ms
Figure 25.
Figure 26.
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OUTPUT VOLTAGE AND ENABLE VOLTAGE
OUTPUT VOLTAGE AND ENABLE VOLTAGE
vs
vs
TIME (START-UP)
TIME (START-UP)
V = 1.5 V
O
V
= 3.3 V
O
C
I
= 33 mF
O
3
2
1
0
3
2
1
0
C
I
= 33 mF
O
= 125 mA
= 250 mA
O
O
V = Standby
OUT1
V
= Standby
OUT2
5
0
5
0
0
0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0
0
0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0
T - Time - ms
T - Time - ms
Figure 27.
Figure 28.
To Load
VIN
IN
OUT
+
COUT
RL
EN
GND
ESR
Figure 29. Test Circuit for Typical Regions of Stability
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TYPICAL REGION OF STABILITY
EQUIVALENT SERIES RESISTANCE(1)
vs
TYPICAL REGION OF STABILITY
EQUIVALENT SERIES RESISTANCE(1)
vs
OUTPUT CURRENT
OUTPUT CURRENT
10
10
REGION OF INSTABILITY
REGION OF INSTABILITY
V
= 3.3 V
O
V
= 3.3 V
O
C
T
= 10 mF
O
C
T
= 6.8 mF
O
= +25°C
J
= +25°C
J
1
1
0.1
50 mW
250 mW
REGION OF INSTABILITY
REGION OF INSTABILITY
0.1
0.01
0
50
100
150
200
250
0
50
I
100
150
200
250
I
- Output Current - mA
- Output Current - mA
O
O
Figure 30.
Figure 31.
TYPICAL REGION OF STABILITY
EQUIVALENT SERIES RESISTANCE(1)
vs
TYPICAL REGION OF STABILITY
EQUIVALENT SERIES RESISTANCE(1)
vs
OUTPUT CURRENT
OUTPUT CURRENT
10
10
REGION OF INSTABILITY
REGION OF INSTABILITY
V
= 1.8 V
O
V
= 1.8 V
O
C
T
= 6,8 mF
O
C
T
= 10 mF
O
= +25°C
J
= +25°C
1
J
1
0.1
50 mW
250 mW
REGION OF INSTABILITY
REGION OF INSTABILITY
0.1
0.01
0
25
50
75
100
125
0
25
50
75
100
125
I
- Output Current - mA
I
- Output Current - mA
O
O
Figure 32.
Figure 33.
(1) Equivalent series resistance (ESR) refers to the total series resistance, including the ESR of the capacitor, any
series resistance added externally, and PWB trace resistance to CO.
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SLVS301D–JUNE 2000–REVISED DECEMBER 2007
APPLICATION INFORMATION
TPS708xxPWP
(Fixed Output Option)
Sequencing Timing Diagrams
V
OUT1
V
IN
This section provides a number of timing diagrams
showing how this device functions in different
configurations.
V
V
IN1
OUT1
10 mF
0.1 mF
V
SENSE1
Application condition: VIN1 and VIN2 are tied to the
same fixed input voltage greater than VUVLO. PG2 is
tied to MR.
250 kW
250 kW
PG1
MR
MR
V
IN2
EN1 and EN2 are initially high; therefore, both
regulators are off, and PG1 and PG2 (tied to MR) are
at logic low. Since MR is at logic low, RESET is also
at logic low. When EN1 is taken to logic low, VOUT1
turns on. Later, when EN2 is taken to logic low, VOUT2
turns on. When VOUT1 reaches 95% of its regulated
output voltage, PG1 goes to logic high. When VOUT2
reaches 95% of its regulated output voltage, PG2
(tied to MR) goes to logic high. When VIN1 is greater
than VUVLO and MR (tied to PG2) is at logic high,
RESET is pulled to logic high after a 120-ms delay.
When EN1 and EN2 return to logic high, both devices
power down and both PG1, PG2 (tied to MR2), and
RESET return to logic low.
RESET
0.1 mF
RESET
PG2
PG2
EN1
EN1
EN2
>2 V
>2 V
<0.7 V
EN2
V
SENSE2
V
OUT2
V
OUT2
<0.7 V
10 mF
EN2
EN1
95%
V
OUT2
95%
V
OUT1
PG2
PG1
MR
(PG2 tied to MR)
RESET
t1
120 ms
NOTES: A. t1: Time at which VIN is greater than VUVLO and MR is logic high.
B. The timing diagram is not drawn to scale.
Figure 34. Timing When VOUT1 Is Enabled Before VOUT2
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Application condition: VIN1 and VIN2 are tied to the
same fixed input voltage greater than VUVLO. MR is
initially logic high but is eventually toggled.
TPS708xxPWP
(Fixed Output Option)
V
IN
V
OUT1
V
OUT1
V
IN1
EN1 and EN2 are initially high; therefore, both
regulators are off, and PG1 and PG2 are at logic low.
Since VIN1 is greater than VUVLO and MR is at logic
high, RESET is also at logic high. When EN2 is taken
to logic low, VOUT2 turns on. Later, when EN1 is taken
to logic low, VOUT1 turns on. When VOUT2 reaches
95% of its regulated output voltage, PG2 goes to
logic high. When VOUT1 reaches 95% of its regulated
output voltage, PG1 goes to logic high. When MR is
taken to logic low, RESET is taken low. When MR
returns to logic high, RESET returns to logic high
after a 120-ms delay.
250 kW
0.1 mF
V
SENSE1
10 mF
250 kW
PG1
V
IN2
250 kW
0.1 mF
RESET
RESET
PG2
PG2
MR
EN1
EN1
EN2
>2 V
>2 V
MR
2 V
V
0.7 V
OUT2
10 mF
<0.7 V
EN2
SENSE2
V
V
OUT2
<0.7 V
EN2
EN1
95%
V
OUT2
95%
V
OUT1
PG2
PG1
MR
RESET
t1
120 ms
NOTES: A. t1: Time at which VIN is greater than VUVLO and MR is logic high.
B. The timing diagram is not drawn to scale.
Figure 35. Timing When MR is Toggled
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Application condition: VIN1 and VIN2 are tied to
same fixed input voltage greater than VUVLO. PG1 is
tied to MR.
TPS708xxPWP
(Fixed Output Option)
V
OUT1
V
IN
V
OUT1
V
IN1
EN1 and EN2 are initially high; therefore, both
regulators are off, and PG1 (tied to MR) and PG2 are
at logic low. Since MR is at logic low, RESET is also
at logic low. When EN2 is taken to logic low, VOUT2
turns on. Later, when EN1 is taken to logic low, VOUT1
turns on. When VOUT2 reaches 95% of its regulated
output voltage, PG2 goes to logic high. When VOUT1
reaches 95% of its regulated output voltage, PG1
goes to logic high. When VIN1 is greater than VUVLO
and MR (tied to PG2) is at logic high, RESET is
pulled to logic high after a 120-ms delay. When a
fault on VOUT1 causes it to fall below 95% of its
regulated output voltage, PG1 (tied to MR) goes to
logic low. Since MR is logic low, RESET goes to logic
low. VOUT2 is unaffected.
0.1 mF
10 mF
V
SENSE1
250 kW
PG1
MR
V
IN2
250 kW
RESET
0.1 mF
RESET
PG2
PG2
EN1
EN1
EN2
>2 V
>2 V
V
SENSE2
<0.7 V
EN2
V
OUT2
V
OUT2
<0.7 V
10 mF
EN2
EN1
95%
V
OUT2
95%
V
OUT1
FAULT ON VOUT1
PG2
PG1
MR
(PG1 tied to MR)
RESET
t1
120 ms
NOTES: A. t1: Time at which VIN is greater than VUVLO and MR is logic high.
B. The timing diagram is not drawn to scale.
Figure 36. Timing When There is a Fault on VOUT1
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SLVS301D–JUNE 2000–REVISED DECEMBER 2007
APPLICATION INFORMATION
Input Capacitor
For a typical application, an input bypass capacitor (0.1 µF to 1 µF) is recommended. This capacitor will filter any
high frequency noise generated in the line. For fast transient conditions where droop at the input of the LDO may
occur because of high inrush current, it is recommended to place a larger capacitor at the input as well. The size
of this capacitor depends on the output current and response time of the main power supply, as well as the
distance to the VI pins of the LDO.
Output Capacitor
As with most LDO regulators, the TPS708xx requires an output capacitor connected between OUT and GND to
stabilize the internal control loop. The minimum recommended capacitance values are 10-µF ceramic capacitors
with an ESR (equivalent series resistance) between 50-mΩ and 2.5-Ω or 6.8-µF tantalum capacitors with ESR
between 250 mΩ and 4 Ω. Solid tantalum electrolytic, aluminum electrolytic, and multilayer ceramic capacitors
with capacitance values greater than 10 µF are all suitable, provided they meet the requirements described
above. Larger capacitors provide a wider range of stability and better load transient response. Table 1 gives a
partial listing of surface-mount capacitors suitable for use with the TPS708xx for fast transient response
application.
This information, along with the ESR graphs, is included to assist in selection of suitable capacitance for user
applications. When necessary to achieve low height requirements along with high output current and/or high load
capacitance, several higher ESR capacitors can be used in parallel to meet the guidelines above.
Table 1. Partial Listing of TPS708xx-Compatible Surface-Mount Capacitors
VALUE
22 µF
33 µF
47 µF
68 µF
MANUFACTURER
Kemet
MAX ESR
345 mΩ
100 mΩ
100 mΩ
45 mΩ
MFR PART NO.
7495C226K0010AS
10TPA33M
Sanyo
Sanyo
6TPA47M
Sanyo
10TPC68M
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SLVS301D–JUNE 2000–REVISED DECEMBER 2007
ESR and Transient Response
LDOs typically require an external output capacitor for stability. In fast transient response applications, capacitors
are used to support the load current while the LDO amplifier is responding. In most applications, one capacitor is
used to support both functions.
Besides its capacitance, every capacitor also contains parasitic impedances. These parasitic impedances are
resistive as well as inductive. The resistive impedance is called equivalent series resistance (ESR), and the
inductive impedance is called equivalent series inductance (ESL). The equivalent schematic diagram of any
capacitor can therefore be drawn as shown in Figure 37.
RSER
LESL
C
Figure 37. ESR and ESL
In most cases one can neglect the effect of inductive impedance ESL. Therefore, the following application
focuses mainly on the parasitic resistance ESR.
Figure 38 shows the output capacitor and its parasitic resistances in a typical LDO output stage.
I
OUT
LDO
-
ESR
R
ESR
V
+
+
V
I
V
OUT
R
LOAD
-
C
OUT
Figure 38. LDO Output Stage with Parasitic Resistances ESR
In steady state (dc state condition), the load current is supplied by the LDO (solid arrow) and the voltage across
the capacitor is the same as the output voltage (V(CO) = VOUT). This condition means no current is flowing into the
CO branch. If IOUT suddenly increases (a transient condition), the following results occur:
•
The LDO is not able to supply the sudden current need because of its response time. Therefore, capacitor CO
provides the current for the new load condition (dashed arrow). CO now acts like a battery with an internal
resistance, ESR. Depending on the current demand at the output, a voltage drop occurs at RESR. This voltage
is shown as VESR in Figure 38.
•
When CO is conducting current to the load, initial voltage at the load will be VO = V(CO) – VESR. As a result of
the discharge of CO, the output voltage VO drops continuously until the response time t1 of the LDO is
reached and the LDO resumes supplying the load. From this point, the output voltage starts rising again until
it reaches the regulated voltage. This period is shown as t2 in Figure 39.
26
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Copyright © 2000–2007, Texas Instruments Incorporated
TPS70845, TPS70848
TPS70851, TPS70858
TPS70802
www.ti.com
SLVS301D–JUNE 2000–REVISED DECEMBER 2007
IOUT
VOUT
1
2
3
ESR 1
ESR 2
ESR 3
t1
t2
Figure 39. Correlation of Different ESRs and Their Influence on the Regulation of VO at a Load Step from
Low-to-High Output Current
Figure 39 also shows the impact of different ESRs on the output voltage. The left brackets show different levels
of ESRs where number 1 displays the lowest and number 3 displays the highest ESR.
From above, the following conclusions can be drawn:
•
•
The higher the ESR, the larger the droop at the beginning of load transient.
The smaller the output capacitor, the faster the discharge time and the greater the voltage droop during the
LDO response period.
Copyright © 2000–2007, Texas Instruments Incorporated
Submit Documentation Feedback
27
TPS70845, TPS70848
TPS70851, TPS70858
TPS70802
www.ti.com
SLVS301D–JUNE 2000–REVISED DECEMBER 2007
Programming the TPS70802 Adjustable LDO Regulator
The output voltage of the TPS70802 adjustable regulators is programmed using external resistor dividers as
shown in Figure 40.
Resistors R1 and R2 should be chosen for approximately a 50-µA divider current. Lower value resistors can be
used, but offer no inherent advantage and waste more power. Higher values should be avoided as leakage
currents at the sense terminal increase the output voltage error. The recommended design procedure is to
choose R2 = 30.1 kΩ to set the divider current at approximately 50 µA, and then calculate R1 using Equation 1:
VOUT
R1 =
- 1 ´ R2
(
(
VREF
(1)
where:
•
VREF = 1.224 V typ (the internal reference voltage)
OUTPUT VOLTAGE
PROGRAMMING GUIDE
TPS70802
OUTPUT
VOLTAGE
V
I
R1
R2
UNIT
IN
0.1 mF
2.5 V
3.3 V
3.6 V
31.6
51.1
59.0
30.1
30.1
30.1
kW
kW
kW
>2.0 V
EN
OUT
FB
V
O
<0.7 V
+
R1
GND
R2
Figure 40. TPS70802 Adjustable LDO Regulator Programming
Regulator Protection
Both TPS708xx PMOS-pass transistors have built-in back diodes that conduct reverse currents when the input
voltage drops below the output voltage (for example, during power-down). Current is conducted from the output
to the input and is not internally limited. When extended reverse voltage is anticipated, external limiting may be
appropriate.
The TPS708xx also features internal current limiting and thermal protection. During normal operation, the
TPS708xx regulator 1 limits output current to approximately 1.6 A (typ) and regulator 2 limits output current to
approximately 750 mA (typ). When current limiting engages, the output voltage scales back linearly until the
overcurrent condition ends. While current limiting is designed to prevent gross device failure, care should be
taken not to exceed the power dissipation ratings of the package. If the temperature of the device exceeds
+150°C (typ), thermal-protection circuitry shuts it down. Once the device has cooled below +130°C (typ),
regulator operation resumes.
28
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Copyright © 2000–2007, Texas Instruments Incorporated
TPS70845, TPS70848
TPS70851, TPS70858
TPS70802
www.ti.com
SLVS301D–JUNE 2000–REVISED DECEMBER 2007
Power Dissipation and Junction Temperature
Specified regulator operation is assured to a junction temperature of +125°C; the maximum junction temperature
should be restricted to +125°C under normal operating conditions. This restriction limits the power dissipation the
regulator can handle in any given application. To ensure the junction temperature is within acceptable limits,
calculate the maximum allowable dissipation, PD(max), and the actual dissipation, PD, which must be less than or
equal to PD(max)
.
The maximum-power-dissipation limit is determined using the following equation:
TJ max *TA
PD(max)
+
RqJA
(2)
where:
•
•
TJmax is the maximum allowable junction temperature
RθJA is the thermal resistance junction-to-ambient for the package, that is, 32.6°C/W for the 20-terminal PWP with no
airflow.
•
TA is the ambient temperature
The regulator dissipation is calculated using:
ǒ
Ǔ
PD + VI*VO IO
(3)
Power dissipation resulting from quiescent current is negligible. Excessive power dissipation triggers the thermal
protection circuit.
Copyright © 2000–2007, Texas Instruments Incorporated
Submit Documentation Feedback
29
PACKAGE OPTION ADDENDUM
www.ti.com
30-Jul-2011
PACKAGING INFORMATION
Status (1)
Eco Plan (2)
MSL Peak Temp (3)
Samples
Orderable Device
Package Type Package
Drawing
Pins
Package Qty
Lead/
Ball Finish
(Requires Login)
TPS70802PWP
TPS70802PWPG4
TPS70845PWP
ACTIVE
ACTIVE
ACTIVE
ACTIVE
ACTIVE
ACTIVE
ACTIVE
ACTIVE
ACTIVE
ACTIVE
ACTIVE
ACTIVE
HTSSOP
HTSSOP
HTSSOP
HTSSOP
HTSSOP
HTSSOP
HTSSOP
HTSSOP
HTSSOP
HTSSOP
HTSSOP
HTSSOP
PWP
PWP
PWP
PWP
PWP
PWP
PWP
PWP
PWP
PWP
PWP
PWP
20
20
20
20
20
20
20
20
20
20
20
20
70
70
Green (RoHS
& no Sb/Br)
CU NIPDAU Level-2-260C-1 YEAR
Green (RoHS
& no Sb/Br)
CU NIPDAU Level-2-260C-1 YEAR
CU NIPDAU Level-2-260C-1 YEAR
CU NIPDAU Level-2-260C-1 YEAR
CU NIPDAU Level-2-260C-1 YEAR
CU NIPDAU Level-2-260C-1 YEAR
CU NIPDAU Level-2-260C-1 YEAR
CU NIPDAU Level-2-260C-1 YEAR
CU NIPDAU Level-2-260C-1 YEAR
CU NIPDAU Level-2-260C-1 YEAR
CU NIPDAU Level-2-260C-1 YEAR
CU NIPDAU Level-2-260C-1 YEAR
70
Green (RoHS
& no Sb/Br)
TPS70845PWPG4
TPS70848PWP
70
Green (RoHS
& no Sb/Br)
70
Green (RoHS
& no Sb/Br)
TPS70848PWPG4
TPS70851PWP
70
Green (RoHS
& no Sb/Br)
70
Green (RoHS
& no Sb/Br)
TPS70851PWPG4
TPS70851PWPR
TPS70851PWPRG4
TPS70858PWP
70
Green (RoHS
& no Sb/Br)
2000
2000
70
Green (RoHS
& no Sb/Br)
Green (RoHS
& no Sb/Br)
Green (RoHS
& no Sb/Br)
TPS70858PWPG4
70
Green (RoHS
& no Sb/Br)
(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.
Addendum-Page 1
PACKAGE OPTION ADDENDUM
www.ti.com
30-Jul-2011
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.
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
14-Jul-2012
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)
TPS70851PWPR
HTSSOP PWP
20
2000
330.0
16.4
6.95
7.1
1.6
8.0
16.0
Q1
Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
14-Jul-2012
*All dimensions are nominal
Device
Package Type Package Drawing Pins
HTSSOP PWP 20
SPQ
Length (mm) Width (mm) Height (mm)
367.0 367.0 38.0
TPS70851PWPR
2000
Pack Materials-Page 2
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