TI TPS71334DRCTG4

TPS71319
TPS71334
www.ti.com
SBVS055A – DECEMBER 2004 – REVISED JANUARY 2005
Dual 250 mA Output, UltraLow Noise, High PSRR,
Low-Dropout Linear Regulator with Integrated SVS
FEATURES
•
•
•
•
•
•
•
•
•
•
•
•
DESCRIPTION
Dual 250 mA High-Performance RF LDOs
Integrated Supply Voltage Supervisor
Monitors VOUT2
Available in Fixed and Adjustable
Voltage Options (1.2 V to 5.5 V)
High PSRR: 65 dB at 10 kHz
UltraLow Noise: 32 µVrms
Fast Start-Up Time: 60 µs
Stable with 2.2 µF Ceramic Capacitor
Excellent Load/Line Transient Response
Very Low Dropout Voltage: 125 mV at 250 mA
Independent Enable Pins
Thermal Shutdown and Independent Current
Limit
Available in Thermally-Enhanced SON
Package: 3mm x 3mm x 1mm
The TPS713xx family of low-dropout (LDO) voltage
regulators is tailored to noise-sensitive and RF applications. These products feature dual 250 mA LDOs
with ultralow noise, high power-supply rejection ratio
(PSRR), and fast transient and start-up response.
These devices also feature an integrated supply
voltage supervisor (SVS) that monitors the voltage at
OUT2 and will assert if the voltage falls to 95%
(typical) of the measured output. Each regulator
output is stable with low-cost 2.2 µF ceramic output
capacitors and features very low dropout voltages
(125 mV typical at 250 mA). Each regulator achieves
fast start-up times (approximately 60 µs with a
0.001 µF bypass capacitor) while consuming very low
quiescent current (300 µA typical with both outputs
enabled). When the device is placed in standby
mode, the supply current is reduced to less than
0.3 µA typical. Each regulator exhibits approximately
32 µVrms of output voltage noise with VOUT = 2.8 V
and a 0.01 µF noise reduction (NR) capacitor. Applications with
analog components
that
are
noise-sensitive, such as portable RF electronics, will
benefit from high PSRR, low noise, and fast line and
load transient features. The TPS713xx family is
offered in a thin 3mm x 3mm SON package and is
fully specified from -40°C to +125°C (TJ).
APPLICATIONS
•
•
•
•
•
Cellular and Cordless Phones
Wireless PDA/Handheld Products
PCMCIA/Wireless LAN Applications
Digital Camera/Camcorder/Internet Audio
DSP/FPGA/ASIC/Controllers and Processors
PSRR (RIPPLE REJECTION) vs FREQUENCY
80
70
IN 1
RESET 2
OUT1 3
OUT2 4
GND 5
10 EN1
9 NC
8 EN2
7 FB2/NC
IOUT = 250 mA
60
PSRR (dB)
DRC PACKAGE
3mm x 3mm SON
(TOP VIEW)
50
40
IOUT = 1 mA
30
20
VOUT = 2.8 V (adj)
COUT = 2.2 µF
CNR = 0.01 µF
6 NR
10
0
10
100
1k
10k
100k
1M
10M
Frequency (Hz)
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.
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 © 2004–2005, Texas Instruments Incorporated
TPS71319
TPS71334
www.ti.com
SBVS055A – DECEMBER 2004 – REVISED JANUARY 2005
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 (TJ)
PRODUCT
VOUT1
VOUT2
PACKAGELEAD
(DESIGNATOR)
TPS71319
1.8 V
Adjustable
SON-10 (DRC)
-40°C to +125°C
ARP
TPS71334
3.3 V
Adjustable
SON-10 (DRC)
-40°C to +125°C
ARO
(1)
SPECIFIED
TEMPERATURE
RANGE (TJ)
PACKAGE
MARKING
ORDERING
NUMBER
TRANSPORT
MEDIA, QUANTITY
TPS71319DRCT
Tape and Reel, 250
TPS71319DRCR
Tape and Reel, 3000
TPS71334DRCT
Tape and Reel, 250
TPS71334DRCR
Tape and Reel, 3000
For the most current package and ordering information, see the Package Ordering Addendum located at the end of this data sheet.
ABSOLUTE MAXIMUM RATINGS
over operating junction temperature range unless otherwise noted (1)
TPS713xx
UNIT
-0.3 to 6.0
V
VRESET range
-0.3 to VIN + 0.3
V
VEN1, VEN2 range
-0.3 to VIN + 0.3
V
-0.3 to 6.0
V
VIN range
VOUT range
Peak output current
Internally limited
Output short-circuit duration
Indefinite
Continuous total power dissipation
See Dissipation Ratings Table
Junction temperature range, TJ
-40 to +150
Storage temperature range
°C
-65 to +150
°C
ESD rating, HBM
2
kV
ESD rating, CDM
500
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 the Electrical Characteristics
is not implied. Exposure to absolute maximum rated conditions for extended periods may affect device reliability.
POWER DISSIPATION RATINGS
BOARD
PACKAGE
RθJC
RθJA
DERATING FACTOR
ABOVE TA = 25°C
TA ≤ 25°C
POWER RATING
TA = 70°C
POWER RATING
TA = 85°C
POWER RATING
High-K (1)
DRC
48
52
19 mW/°C
1.92 W
1.06 W
0.77 W
(1)
2
The JEDEC High-K (2s2p) board design used to derive this data was a 3 inch x 3 inch, multilayer board with 1-ounce internal power and
ground planes and 2-ounce copper traces on the top and bottom of the board.
TPS71319
TPS71334
www.ti.com
SBVS055A – DECEMBER 2004 – REVISED JANUARY 2005
ELECTRICAL CHARACTERISTICS
Over operating temperature range (TJ = -40°C to +125°C), VIN = highest VOUT(nom) + 1.0 V or 2.7 V (whichever is greater),
IOUT = 1 mA, VEN1, 2 = 1.2 V, COUT = 10 µF, CNR = 0.01 µF, and adjustable LDOs are tested at VOUT = 3.0 V, unless otherwise
noted. Typical values are at TJ = 25°C.
PARAMETER
TEST CONDITIONS
MIN
range (1)
VIN
Input voltage
VFB
Internal reference (adjustable LDOs)
Accuracy (1)
MAX
5.5
V
1.225
1.250
V
VFB
5.5 - VDO
V
-1.5
+1.5
2.7
1.200
Output voltage range
(adjustable LDOs)
VOUT
TYP
Nominal
TJ = 25°C, IOUT = 0 mA
Over VIN,
IOUT, and T
VOUT + 1.0 V ≤ VIN ≤ 5.5 V,
0 µA ≤ IOUT ≤ 250 mA
-3
±1
+3
UNIT
%
∆VOUT%/∆VIN
Line regulation (1)
VOUT + 1.0 V ≤ VIN ≤ 5.5 V
0.05
%/V
∆VOUT%/∆IOUT
Load regulation
0 µA ≤ IOUT ≤ 250 mA
0.8
%/mA
VDO
Dropout voltage (2)
(VIN = VOUT(nom) - 0.1V)
IOUT1 = IOUT2 = 250 mA
125
230
mV
ICL
Output current limit
600
800
mA
IGND
Ground pin current
2.8 V,
2.85 V
Adjustable
VOUT = 0.9 × VOUT(nom)
400
One LDO
enabled
IOUT = 1 mA (enabled channel)
190
250
Both LDOs
enabled
IOUT1 = IOUT2 = 1 mA to 250 mA
300
600
VEN ≤ 0.4 V, 0 V ≤ VIN ≤ 5.5 V,
RESET open
0.3
2.0
µA
0.1
1
µA
ISHDN
Shutdown current (3)
IFB
FB pin current (adjustable LDOs)
µA
80.0 × VOUT
CNR = 0.01 µF, IOUT = 250 mA
11.8 × VOUT
Vn
Output noise voltage,
BW = 10 Hz - 100 kHz
No CNR, IOUT = 250 mA
PSRR
Power-supply rejection ratio
(ripple rejection)
f = 100 Hz, IOUT = 250 mA
65
f = 10 kHz, IOUT = 250 mA
65
tSTR
Startup time
VOUT = 2.85 V, RL = 30Ω, CNR = 0.001 µF
60
VIH
Enable threshold high (EN1, EN2)
VIL
Enable threshold low (EN1, EN2)
IEN
Enable pin current (EN1, EN2)
VIN = VEN = 5.5 V
Minimum VIN for valid RESET
IRESET = 10 µA
RESET output low voltage
IRESET = 1 mA
ILKG, RESET
RESET leakage current
VIN = VRESET = 5.5 V
VIT
RESET threshold voltage
VOUT2 falling (4)
VHYS
RESET threshold hysteresis
VOUT2 rising (4)
TD
RESET delay time
TP
RESET propagation delay
TSD
Thermal shutdown temperature
VRESET,
UVLO
(1)
(2)
(3)
(4)
LO
µVrms
dB
µs
1.2
VIN
0
0.4
V
-1
1
µA
0.6
10
92.5
V
0.4
V
500
nA
97.5
%VOUT
0.5
50
100
%VOUT
200
10
Shutdown
Temp increasing
+160
Reset
Temp decreasing
+140
Under-voltage lockout threshold
VIN rising
Under-voltage lockout hysteresis
VIN falling
2.25
ms
µs
°C
2.65
100
V
V
mV
Minimum VIN = VOUT + VDO or 2.7 V, whichever is greater.
VDO is not measured for 1.8 V regulators since minimum VIN = 2.7 V.
For the adjustable version, this applies only after VIN is applied; then VEN transitions from high to low.
RESET threshold and hysteresis is a percentage of the measured output.
3
TPS71319
TPS71334
www.ti.com
SBVS055A – DECEMBER 2004 – REVISED JANUARY 2005
FUNCTIONAL BLOCK DIAGRAM
IN
OUT1
30 µA
Current
Limit
EN1
Thermal
Shutdown
OUT2
Current
Limit
UVLO
90 kΩ
FB2
Delay
(VFB2 Rising)
EN2
100 ms
250 kΩ
RESET
0.95 × VREF
NR
VREF
5 pF
1.225 V
Quickstart
TPS713xx
Fixed/Fixed
Table 1. TERMINAL FUNCTIONS
TERMINAL
NAME
4
DESCRIPTION
DRC
IN
1
GND
5, Pad
Unregulated input supply. A 0.1 µF capacitor should be connected from IN to GND.
OUT1
3
Output of the regulator. A small 2.2 µF ceramic capacitor is required from this pin to ground to assure
stability.
OUT2
4
Same as OUT1 but for LDO2.
EN1
10
Driving the enable pin (EN) high turns on LDO1. Driving this pin low puts LDO1 into shutdown mode,
reducing operating current. The enable pin should be connected to IN if not used.
EN2
8
Same as EN1 but controls LDO2.
NC
9
No connection.
FB2/NC
7
Feedback for CH2 adjustable version; no connection for non-adjustable CH2.
NR
6
Noise reduction pin; connect an external bypass capacitor to reduce LDO output noise.
RESET
2
Open-drain reset output; monitors OUT2. A 10 kΩ to 1 MΩ pull-up resistor is suitable for most
applications. The open-drain RESET pull-up voltage should not exceed VDD + 0.3 V.
Ground
TPS71319
TPS71334
www.ti.com
SBVS055A – DECEMBER 2004 – REVISED JANUARY 2005
TYPICAL CHARACTERISTICS
For all voltage versions at TJ = 25°C, VIN = VOUT(nom) + 1 V, IOUT = 1 mA,VEN = 1.2 V, COUT = 2.2 µF, and CNR = 0.01 µF,
unless otherwise noted.
OUTPUT VOLTAGE vs INPUT VOLTAGE
OUTPUT VOLTAGE vs OUTPUT CURRENT
1.0
1.0
0.8
0.8
0.6
0.6
0.4
+25 C
0.2
VOUT (%)
VOUT (%)
0.4
0
−0.2
+125 C
−0.4
−0.6
0
−40C
−0.2
−0.4
−0.6
−40C
−0.8
+25C
0.2
−0.8
−1.0
+125 C
−1.0
3.0
3.5
4.0
4.5
5.0
5.5
6.0
0
50
100
150
200
250
VIN (V)
IOUT (mA)
Figure 1.
Figure 2.
OUTPUT VOLTAGE vs TEMPERATURE
DROPOUT VOLTAGE vs INPUT VOLTAGE
(ADJUSTABLE OUTPUTS)
200
1.0
180
160
VOUT (%)
IOUT = 10 mA
0
IOUT = 125 mA
−0.5
IOUT = 250 mA
−1.0
Dropout Voltage (mV)
0.5
TJ = +125C
140
120
TJ = +25C
100
80
60
TJ = −40C
40
20
−1.5
−40 −25 −10
0
5
20
35
50
65
80
95
2.7
110 125
2.9
3.1
3.3
3.5
3.7
3.9 4.1
Junction Temperature (C)
VIN (V)
Figure 3.
Figure 4.
DROPOUT VOLTAGE vs OUTPUT CURRENT
4.3
4.5 4.7
4.9
DROPOUT VOLTAGE vs JUNCTION TEMPERATURE
200
250
Adjustable Set to 2.8 V
Adjustable Set to 2.8 V
200
150
Dropout Voltage (mV)
Dropout Voltage (mV)
TJ = +125C
100
TJ = −40 C
TJ = +25C
50
150
IOUT = 250 mA
100
50
0
0
50
100
150
200
250
0
−40 −25 −10
5
20
35
50
65
80
IOUT (mA)
Junction Temperature (mA)
Figure 5.
Figure 6.
95
110 125
5
TPS71319
TPS71334
www.ti.com
SBVS055A – DECEMBER 2004 – REVISED JANUARY 2005
TYPICAL CHARACTERISTICS (continued)
For all voltage versions at TJ = 25°C, VIN = VOUT(nom) + 1 V, IOUT = 1 mA,VEN = 1.2 V, COUT = 2.2 µF, and CNR = 0.01 µF,
unless otherwise noted.
GROUND CURRENT vs INPUT VOLTAGE
GROUND PIN CURRENT vs IOUT
400
400
375
375
350
+125 C
325
IGND (µA)
IGND (µA)
350
300
275
−40C
+25C
250
325
+125C
300
275
225
+25 C
−40C
250
225
200
200
2.7
3.2
3.7
4.2
4.7
5.2
5.7
0
50
100
150
200
250
VIN (V)
IOUT (mA)
Figure 7.
Figure 8.
GROUND PIN CURRENT vs JUNCTION TEMPERATURE
GROUND PIN CURRENT vs JUNCTION TEMPERATURE
(DISABLED)
400
500
VEN1 = VEN2 = 1.2 V
375
VEN1 = VEN2 = 0.4V
450
VIN = 3.8 V
VIN = 3.8 V
400
350
IGND (nA)
IGND (µA)
350
325
300
275
300
250
200
150
250
100
225
50
200
−40 −25 −10
0
5
20
35
50
65
80
95
110 125
−40 −25 −10
5
20
35
50
95
Figure 9.
Figure 10.
CURRENT LIMIT vs JUNCTION TEMPERATURE
TPS71334
LINE TRANSIENT RESPONSE
750
110 125
COUT1 = COUT2 = 10µF
VOUT2 Set to 1.225 V
4.3 V
VIN
700
3.8 V
650
600
IOUT = 250 mA
VOUT1
10 mV/div
550
500
IOUT = 1 mA
10 mV/div
450
400
−40 −25 −10
5
20
35
50
65
80
95
110 125
100 µs/div
Junction Temperature (C)
Figure 11.
6
80
Junction Temperature (C)
800
Current Limit (mA)
65
Junction Temperature (C)
Figure 12.
VOUT2
TPS71319
TPS71334
www.ti.com
SBVS055A – DECEMBER 2004 – REVISED JANUARY 2005
TYPICAL CHARACTERISTICS (continued)
For all voltage versions at TJ = 25°C, VIN = VOUT(nom) + 1 V, IOUT = 1 mA,VEN = 1.2 V, COUT = 2.2 µF, and CNR = 0.01 µF,
unless otherwise noted.
TPS71334
LOAD TRANSIENT RESPONSE
AND VOUT2 CROSSTALK
TPS71334
CHANNEL-TO-CHANNEL ISOLATION vs FREQUENCY
60
COUT2 = 10 µF
2 mV/div
VOUT2
100 mV/div
250 mA
VOUT1
VOUT2 Set to 2.225 V
10 mA
200 mA/div
Channel Isolation (dB)
50
COUT1 = 10 µF
IOUT1
40
30
20
10
COUT1 = C OUT2 = 10 µF
IOUT1 = 0 mA to 500 mA Sinusoidal Load
IOUT2 = 25 mA
Adjustable Set to 3.3 V
0
20 µs/div
0.1
1
10
100
1k
Frequency (Hz)
Figure 13.
Figure 14.
TPS71334
TURN-ON/OFF RESPONSE
AND VOUT2 CROSSTALK
TPS71334
POWER-UP/POWER-DOWN
I OUT1 = IOUT2 = 250 mA
COUT1 = COUT 2 = 10 µF
VOUT2 Set to 1.225 V
20 mV/div
IOUT1 = I OUT2 = 250 mA
VOUT2
VOUT2
1 V/div
CNR = 0.001 µF
VOUT2
VIN
VOUT1
1 V/div
VEN1
50 ms/div
Figure 15.
Figure 16.
TOTAL NOISE vs CNR
NOISE SPECTRAL DENSITY
COUT = 2.2 µF
COUT = 2.2 µF
IOUT = 250 mA
200
Total Noise (µVrms)
50 µs/div
COUT = 10 µF
IOUT = 250 mA
150
100
VOUT = 2.8 V (adj)
COUT = 2.2 µF
IOUT = 0 mA
COUT = 10 µF
IOUT = 0 mA
50
0
1
10
100
1k
10k
100k
350
Spectral Noise Density (nV/√Hz)
250
VRESET
300
CNR = 0.1 µF
VOUT = 2.8 V (adj)
IOUT = 250 mA
250
200
IOUT = 1 mA
150
100
50
0
100
1k
10k
CNR (pF)
Frequency (Hz)
Figure 17.
Figure 18.
100k
7
TPS71319
TPS71334
www.ti.com
SBVS055A – DECEMBER 2004 – REVISED JANUARY 2005
TYPICAL CHARACTERISTICS (continued)
For all voltage versions at TJ = 25°C, VIN = VOUT(nom) + 1 V, IOUT = 1 mA,VEN = 1.2 V, COUT = 2.2 µF, and CNR = 0.01 µF,
unless otherwise noted.
NOISE SPECTRAL DENSITY
COUT = 10 µF
NOISE SPECTRAL DENSITY vs CNR
180
CNR = 0.01 µF
VOUT = 2.8 V (adj)
300
Spectral Noise Density (nV/√Hz)
Spectral Noise Density (nV/√Hz)
350
250
200
IOUT = 1 mA
150
IOUT = 250 mA
100
50
0
100
1k
10k
140
0.001 µF
120
100
0.047 µF
80
0.01 µF
60
40
0.1 µF
20
0
100
100k
Figure 19.
Figure 20.
60
50
50
PSRR (dB)
PSRR (dB)
60
40
I OUT = 1 mA
100
1k
40
30
I OUT = 250 mA
20
VOUT = 2.8 V (adj)
COUT = 2.2 µF
CNR = 0.01 µF
10
IOUT = 1 mA
70
IOUT = 250 mA
30
VOUT = 2.8 V (adj)
COUT = 10 µF
CNR = 0.01 µF
10
0
10k
100k
1M
10M
10
100
1k
100k
Frequency (Hz)
Figure 21.
Figure 22.
PSRR (RIPPLE REJECTION) vs VIN - VOUT
80
70
f = 1 kHz
PSRR (dB)
60
50
f = 10 kHz
40
30
f = 100 kHz
VOUT = 2.8 V (adj)
IOUT = 250 mA
COUT = 10 µF
CNR = 0.01 µF
20
10
0
0.2
0.4
0.6
0.8
1.0
1.2
VIN − VOUT (V)
Figure 23.
8
10k
Frequency (Hz)
0
100k
PSRR (RIPPLE REJECTION) vs FREQUENCY
80
70
0
10k
Frequency (Hz)
PSRR (RIPPLE REJECTION) vs FREQUENCY
10
1k
Frequency (Hz)
80
20
COUT = 10 µF
IOUT = 250 mA
VOUT = 2.8 V (adj)
160
1.4
1.6
1.8
2.0
1M
10M
TPS71319
TPS71334
www.ti.com
SBVS055A – DECEMBER 2004 – REVISED JANUARY 2005
APPLICATION INFORMATION
The TPS713xx family of dual low-dropout (LDO)
regulators has been optimized for use in
noise-sensitive battery-operated equipment. The device features extremely low dropout, high PSRR,
ultralow output noise, and low quiescent current
(190 µA typically per channel). When both outputs
are disabled, the supply currents are reduced to less
than 2µA. A typical application circuit with sequencing
is shown in Figure 24.
TPS71334
VIN
IN
VOUT1
OUT1
2.2 µF
100 kΩ
0.1 µF
EN2
RESET
EN1
OUT2
VOUT2
R1
NR
C1
2.2 µF
FB2
GND
R2
0.01 µF
64.9 kΩ
Figure 24. Typical Application Circuit
(with output sequencing)
INPUT AND OUTPUT CAPACITOR
REQUIREMENTS
A 0.1 µF or larger ceramic input bypass capacitor,
connected between IN and GND and located close to
the TPS713xx, is required for stability. It improves
transient response, noise rejection, and ripple rejection. A higher-value input capacitor may be necessary
if large, fast-rise-time load transients are anticipated
and the device is located several inches from the
power source.
The TPS713xx requires an output capacitor connected between the outputs and GND to stabilize the
internal control loops. The minimum recommended
output capacitor is 2.2 µF. If an output voltage of
1.8 V or less is chosen, the minimum recommended
output capacitor is 4.7 µF. Any ceramic capacitor that
meets the minimum output capacitor requirements is
suitable. Capacitors with higher ESR may be used,
provided the worst-case ESR is less than 1Ω.
OUTPUT NOISE
The internal voltage reference is a key source of
noise in an LDO regulator. The TPS713xx has an NR
pin that is connected to the voltage reference through
a 250 kΩ internal resistor. The 250 kΩ internal
resistor, in conjunction with an external ceramic
bypass capacitor connected to the NR pin, creates a
low-pass filter to reduce the voltage reference noise
and, therefore, the noise at the regulator output. To
achieve a fast startup, the 250 kΩ internal resistor is
shorted for 400 µs after the device is enabled.
Because the primary noise source is the internal
voltage reference, the output noise will be greater for
higher output voltage versions. For the case where
no noise reduction capacitor is used, the typical noise
(µVrms) over 10 Hz to 100 kHz is 30 times the output
voltage. If a 0.01 µF capacitor is used from the NR
pin to ground, the noise (µVrms) drops to 11.8 times
the output voltage. For example, the TPS71334 with
the adjustable output set to 2.8 V exhibits only
33 µVrms of output voltage noise using a 0.01 µF
ceramic bypass capacitor and a 2.2 µF ceramic
output capacitor.
STARTUP CHARACTERISTICS
To minimize startup overshoot, the TPS713xx will
initially target an output voltage that is approximately
80% of the final value. To avoid a delayed startup
time, noise reduction capacitors of 0.01 µF or less
are recommended. Larger noise reduction capacitors
will cause the output to hold at 80% until the voltage
on the noise reduction capacitor exceeds 80% of the
bandgap voltage. The typical startup time with a
0.001 µF noise reduction capacitor is 60 µs. Once
one of the output voltages is present, the startup time
of the other output will not be affected by the noise
reduction capacitor.
9
TPS71319
TPS71334
www.ti.com
SBVS055A – DECEMBER 2004 – REVISED JANUARY 2005
PROGRAMMING THE TPS71202
ADJUSTABLE LDO REGULATOR
C1 The output voltage of the TPS71202 dual adjustable
regulator is programmed using an external resistor
divider, as shown in Figure 24. The output voltage is
calculated using Equation 1:
V OUT VREF 1 R1
R2
(1)
where VREF = 1.225 V (the internal reference voltage).
Resistors R2 and R4 should be chosen for approximately a 40 µA divider current. Lower value resistors
can be used for improved noise performance, but will
consume more power. Higher values should be
avoided because leakage current at FB increases the
output voltage error. The recommended design procedure is to choose R2 = 30.1 kΩ to set the divider
current at 40 µA, and then calculate R1 using
Equation 2:
R1 VV
OUT
REF
1 R2
(2)
To improve the stability and noise performance of the
adjustable version, a small compensation capacitor
can be placed between OUT and FB.
(3 105) (R1 R2)
(pF)
(R1 R2)
(3)
The suggested value of this capacitor for several
resistor ratios is shown in Figure 25. If this capacitor
is not used (such as in a unity-gain configuration) or if
an output voltage ≤ 1.8 V is chosen, then the
minimum recommended output capacitor is 4.7 µF
instead of 2.2 µF.
DROPOUT VOLTAGE
The TPS713xx uses a PMOS pass transistor to
achieve extremely low dropout. When (VIN - VOUT) is
less than the dropout voltage (VDO), the PMOS pass
device is in its linear region of operation and the
input-to-output resistance is the RDS, ON of the PMOS
pass element. Dropout voltages at lower currents can
be approximated by calculating the effective RDS, ON
of the pass element and multiplying that resistance by
the load current. RDS, ON of the pass element can be
obtained by dividing the dropout voltage by the rated
output current. For the TPS71334, the RDS, ON of the
pass element is 84 mΩ. The dropout voltage of the
TPS713xx will be less for higher output voltage
versions. This is because the PMOS pass element
will have lower on-resistance due to increased gate
drive.
For voltages ≤ 1.8 V, the value of this capacitor
should be 100 pF. For voltages > 1.8 V, the approximate value of this capacitor can be calculated as
Equation 3:
TPS71334
VIN
IN
VOUT1
OUT1
2.2 µF
0.1 µF
EN2
EN1
RESET
VOUT2
OUT2
R1
NR
FB2
GND
0.01 µF
R2
C1
2.2 µF
Output Voltage Programming Guide
VOUT2
R1
R2
1.225 V
Short
Open
Open
1.5 V
7.15 kΩ
30.1 kΩ
100 pF
2.5 V
31.6 kΩ
30.1 kΩ
22 pF
3.0 V
43.2 kΩ
30.1 kΩ
15 pF
3.3 V
49.9 kΩ
30.1 kΩ
15 pF
4.75 V
86.6 kΩ
30.1 kΩ
15 pF
Figure 25. TPS71334 Adjustable LDO Regulator Programming
10
C1
TPS71319
TPS71334
www.ti.com
SBVS055A – DECEMBER 2004 – REVISED JANUARY 2005
SUPERVISOR DESCRIPTION
The TPS713xx has an on-chip supply voltage supervisor (SVS) that monitors the voltage at OUT2. The
RESET output will assert if VOUT2 is below the reset
threshold (VIT). When OUT2 exceeds the reset
threshold plus hysteresis (VHYS), the RESET output
will remain low for the specified delay time (tD). When
OUT2 is disabled by EN2 or the input voltage is
below the under-voltage lockout (UVLO), the reset
signal is automatically asserted. The functionality of
the reset circuit is shown in Figure 26 and Table 2.
The output accuracy or output divider resistor tolerances have minimal effect on the relative VIT
threshold accuracy. The reset threshold VIT will scale
accordingly to the actual output voltage. The RESET
output will remain unasserted during transients
shorter than the reset circuit propagation delay (TP).
Even with a 2.2 µF output capacitor, typical load
transient conditions will not cause RESET to falsely
assert.
The RESET pin requires an external resistor to pull
the pin high during the unasserted state. A 10 kΩ to 1
MΩ resistor is suitable for most applications. If the
resistance is too low, the pin may not pull low enough
to be recognized as a valid logic signal. If the pull-up
resistor is too large, the reset pin leakage may cause
the device not to pull high enough in the unasserted
state. The pull-up voltage for the RESET pin should
not exceed VIN + 0.3 V; doing so will turn on internal
ESD protection devices and may damage the device.
VIN
0.6 V
0.0 V
VOUT1
VIT + VHYS
VIT
VOUT2
tD = Reset Delay
EN1
= Undefined State
EN2
RESET
tD
tD
Figure 26. RESET Timing Diagram
Table 2. Reset Pin Truth Table
(1)
EN2
UVLO
Asserted
VOUT2
RESET
Asserted
X (1)
Yes
X
Yes
Low
X
X
Yes
High
No
VOUT2 > VIT
No
High
No
VOUT2 < VIT
Yes
X = don't care.
11
TPS71319
TPS71334
www.ti.com
SBVS055A – DECEMBER 2004 – REVISED JANUARY 2005
TRANSIENT RESPONSE
As with any regulator, increasing the size of the
output capacitor will reduce over/undershoot magnitude but increase duration of the transient response.
In the adjustable version, the addition of a capacitor,
CFB, from the output to the feedback pin will also
improve stability and transient response. The transient response of the TPS713xx is enhanced with an
active pull-down that engages when the output is
over-voltaged. The active pull-down decreases the
output recovery time when the load is removed.
Figure 14 in the Typical Characteristics section shows
the output transient response.
SHUTDOWN
Both enable pins are active high and are compatible
with standard TTL-CMOS levels. The device is only
completely disabled when both EN1 and EN2 are
logic low. In this state, the LDO is completely off and
the ground pin current drops to approximately
100 nA. With one output disabled, the ground pin
current is slightly greater than half the nominal value.
When shutdown capability is not required, the enable
pins should be connected to the input supply.
Depending on power dissipation, thermal resistance,
and ambient temperature, the thermal protection
circuit may cycle on and off. This limits the dissipation
of the regulator, protecting it from damage due to
overheating.
Any tendency to activate the thermal protection circuit
indicates excessive power dissipation or an inadequate heatsink. For reliable operation, junction temperature should be limited to +125°C maximum. To
estimate the margin of safety in a complete design
(including heatsink), increase the ambient temperature until the thermal protection is triggered; use
worst-case loads and signal conditions. For good
reliability, thermal protection should trigger at least
+35°C above the maximum expected ambient condition of your application. This produces a worst-case
junction temperature of +125°C at the highest expected ambient temperature and worst-case load.
The internal protection circuitry of the TPS713xx was
designed to protect against overload conditions. It
was not intended to replace proper heatsinking.
Continuously running the TPS713xx into thermal
shutdown will degrade device reliability.
POWER DISSIPATION
INTERNAL CURRENT LIMIT
The TPS713xx internal current limit helps protect the
regulator during fault conditions. During current limit,
the output will source a fixed amount of current that is
largely independent of the output voltage.
The TPS713xx PMOS-pass transistors have a built-in
back diode that conducts reverse current when the
input voltage drops below the output voltage (that is,
during power-down). Current is conducted from the
output to the input and is not internally limited. If
extended reverse voltage operation is anticipated,
external limiting may be appropriate.
THERMAL PROTECTION
Thermal protection disables both outputs when the
junction temperature of either channel rises to approximately +160°C, allowing the device to cool.
When the junction temperature cools to approximately +140°C, the output circuitry is again enabled.
12
The ability to remove heat from the die is different for
each package type, presenting different considerations in the PCB layout. The PCB area around the
device that is free of other components moves the
heat from the device to the ambient air. Performance
data for a JEDEC high-K board is shown in the
Dissipation Ratings table. Using heavier copper will
increase the effectiveness in removing heat from the
device. The addition of plated through-holes to
heat-dissipating layers will also improve the heat-sink
effectiveness.
Power dissipation depends on input voltage and load
conditions. Power dissipation is equal to the product
of the output current times the voltage drop across
the output pass element (VIN to VOUT):
P D (VIN VOUT) I OUT
(4)
Power dissipation can be minimized by using the
lowest possible input voltage necessary to assure the
required output voltage.
PACKAGE OPTION ADDENDUM
www.ti.com
16-May-2005
PACKAGING INFORMATION
Orderable Device
Status (1)
Package
Type
Package
Drawing
Pins Package Eco Plan (2)
Qty
TPS71319DRCR
ACTIVE
SON
DRC
10
3000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
TPS71319DRCRG4
ACTIVE
SON
DRC
10
3000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
TPS71319DRCT
ACTIVE
SON
DRC
10
250
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
TPS71319DRCTG4
ACTIVE
SON
DRC
10
250
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
TPS71334DRCR
ACTIVE
SON
DRC
10
3000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
TPS71334DRCRG4
ACTIVE
SON
DRC
10
3000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
TPS71334DRCT
ACTIVE
SON
DRC
10
250
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
TPS71334DRCTG4
ACTIVE
SON
DRC
10
250
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1 YEAR
Lead/Ball Finish
MSL Peak Temp (3)
(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) 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.
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 1
IMPORTANT NOTICE
Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, modifications,
enhancements, improvements, and other changes to its products and services at any time and to discontinue
any product or service without notice. Customers should obtain the latest relevant information before placing
orders and should verify that such information is current and complete. All products are sold subject to TI’s terms
and conditions of sale supplied at the time of order acknowledgment.
TI warrants performance of its hardware products to the specifications applicable at the time of sale in
accordance with TI’s standard warranty. Testing and other quality control techniques are used to the extent TI
deems necessary to support this warranty. Except where mandated by government requirements, testing of all
parameters of each product is not necessarily performed.
TI assumes no liability for applications assistance or customer product design. Customers are responsible for
their products and applications using TI components. To minimize the risks associated with customer products
and applications, customers should provide adequate design and operating safeguards.
TI does not warrant or represent that any license, either express or implied, is granted under any TI patent right,
copyright, mask work right, or other TI intellectual property right relating to any combination, machine, or process
in which TI products or services are used. Information published by TI regarding third-party products or services
does not constitute a license from TI to use such products or services or a warranty or endorsement thereof.
Use of such information may require a license from a third party under the patents or other intellectual property
of the third party, or a license from TI under the patents or other intellectual property of TI.
Reproduction of information in TI data books or data sheets is permissible only if reproduction is without
alteration and is accompanied by all associated warranties, conditions, limitations, and notices. Reproduction
of this information with alteration is an unfair and deceptive business practice. TI is not responsible or liable for
such altered documentation.
Resale of TI products or services with statements different from or beyond the parameters stated by TI for that
product or service voids all express and any implied warranties for the associated TI product or service and
is an unfair and deceptive business practice. TI is not responsible or liable for any such statements.
Following are URLs where you can obtain information on other Texas Instruments products and application
solutions:
Products
Applications
Amplifiers
amplifier.ti.com
Audio
www.ti.com/audio
Data Converters
dataconverter.ti.com
Automotive
www.ti.com/automotive
DSP
dsp.ti.com
Broadband
www.ti.com/broadband
Interface
interface.ti.com
Digital Control
www.ti.com/digitalcontrol
Logic
logic.ti.com
Military
www.ti.com/military
Power Mgmt
power.ti.com
Optical Networking
www.ti.com/opticalnetwork
Microcontrollers
microcontroller.ti.com
Security
www.ti.com/security
Telephony
www.ti.com/telephony
Video & Imaging
www.ti.com/video
Wireless
www.ti.com/wireless
Mailing Address:
Texas Instruments
Post Office Box 655303 Dallas, Texas 75265
Copyright  2005, Texas Instruments Incorporated