TPS789 [TI]
具有旁路和使能功能的 100mA、10V、低 IQ、低压降稳压器;
| 型号： | TPS789 |
| 厂家： | 
TEXAS INSTRUMENTS |
| 描述： | 具有旁路和使能功能的 100mA、10V、低 IQ、低压降稳压器 电源电路 线性稳压器IC |
| 文件： | 总16页 (文件大小：302K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
TPS78915, TPS78918, TPS78925, TPS78928, TPS78930
ULTRALOW-POWER LOW-NOISE 100-mA
LOW-DROPOUT LINEAR REGULATORS
SLVS300A – SEPTEMBER 2000 – REVISED MAY 2001
DBV PACKAGE
(TOP VIEW)
100-mA Low-Dropout Regulator
Available in 1.5-V, 1.8-V, 2.5-V, 2.8-V, 3.0-V
1
2
3
5
OUT
IN
Output Noise Typically 56 µV
(TPS78930)
RMS
GND
Only 17 µA Quiescent Current at 100 mA
1 µA Quiescent Current in Standby Mode
4
BYPASS
EN
Dropout Voltage Typically 115 mV at 100 mA
(TPS78930)
TPS78930
GROUND CURRENT
vs
Over Current Limitation
–40°C to 125°C Operating Junction
JUNCTION TEMPERATURE
21
20
19
18
17
16
15
14
Temperature Range
V = 4 V
5-Pin SOT-23 (DBV) Package
I
C
= 4.7 µF
o
description
I
O
= 100 mA
The TPS789xx family of low-dropout (LDO)
voltage regulators offers the benefits of
low-dropout voltage, ultralow-power operation,
low-output noise, and miniaturized packaging.
These regulators feature low-dropout voltages
and ultralow quiescent current compared to
conventional LDO regulators. An internal resistor,
in conjunction with an external bypass capacitor,
creates a low-pass filter to reduce the noise. The
I
= 1 mA
O
TPS78930 exhibits only 56 µV
of output
RMS
voltage noise using 0.01 µF bypass and 10 µF
output capacitors. Offered in a 5-terminal small
outline integrated-circuit SOT-23 package, the
TPS789xx series devices are ideal for
micropower operations, low output noise, and
where board space is limited.
–40 –25 –10
5
20 35 50 65 80
110 125
95
T
– Junction Temperature – °C
J
TPS78930
OUTPUT SPECTRAL NOISE DENSITY
vs
FREQUENCY
The usual PNP pass transistor has been replaced
by a PMOS pass element. Because the PMOS
pass element behaves as a low-value resistor, the
dropout voltage is very low, typically 115 mV at
100 mA of load current (TPS78930), and is
directly proportional to the load current. The
quiescent current is ultralow (17 µA typically) and
is stable over the entire range of output load
current (0 mA to 100 mA). Intended for use in
portable systems such as laptops and cellular
phones, the ultralow-dropout voltage feature and
ultralow-power operation result in a significant
increase in system battery operating life.
1200
1000
800
V = 4 V
I
C
C
= 4.7 µF
o
(byp)
= 0.1 µF
600
I
O
= 100 mA
400
I
O
= 1 mA
1k
200
0
100
10k
100k
f – 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.
Copyright 2001, Texas Instruments Incorporated
PRODUCTION DATA information is 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.
1
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
TPS78915, TPS78918, TPS78925, TPS78928, TPS78930
ULTRALOW-POWER LOW-NOISE 100-mA
LOW-DROPOUT LINEAR REGULATORS
SLVS300A – SEPTEMBER 2000 – REVISED MAY 2001
description (continued)
The TPS789xx also features a logic-enabled sleep mode to shut down the regulator, reducing quiescent current
to 1 µA typical at T = 25°C. The TPS789xx is offered in 1.5 V, 1.8 V, 2.5 V, 2.8 V, and 3.0 V.
J
AVAILABLE OPTIONS
T
VOLTAGE
1.5 V
PACKAGE
PART NUMBER
SYMBOL
PDWI
PDXI
J
†
†
†
†
†
‡
‡
‡
‡
‡
TPS78915DBVT
TPS78918DBVT
TPS78925DBVT
TPS78928DBVT
TPS78930DBVT
TPS78915DBVR
TPS78918DBVR
TPS78925DBVR
TPS78928DBVR
TPS78930DBVR
1.8 V
SOT-23
(DBV)
–40°C to 125°C
2.5 V
PDYI
2.8 V
PDZI
3.0 V
PEAI
†
‡
The DBVT indicates tape and reel of 250 parts.
The DBVR indicates tape and reel of 3000 parts.
functional block diagram
TPS78915/18/25/28/30
OUT
IN
EN
150 k
Current Limit
/ Thermal
Protection
V
ref
GND
Bypass
Terminal Functions
TERMINAL
I/O
DESCRIPTION
NAME
NO.
BYPASS
4
I
The external bypass capacitor, in conjunction with an internal resistor, creates a low-pass filter to further reduce
regulator noise.
EN
3
2
1
5
I
Active low enable.
GND
IN
Regulator ground
I
The IN terminal is the input to the device.
The OUT terminal is the regulated output of the device.
OUT
O
2
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
TPS78915, TPS78918, TPS78925, TPS78928, TPS78930
ULTRALOW-POWER LOW-NOISE 100-mA
LOW-DROPOUT LINEAR REGULATORS
SLVS300A – SEPTEMBER 2000 – REVISED MAY 2001
detail description
The TPS789xx uses a PMOS pass element to dramatically reduce both dropout voltage and supply current over
more conventional PNP-pass-element LDO designs. The PMOS pass element is a voltage-controlled device
and, unlike a PNP transistor, it does not require increased drive current as output current increases. Supply
current in the TPS789xx is essentially constant from no load to maximum load.
The TPS789xx family of low-dropout (LDO) regulators have been optimized for use in battery-operated
equipment. They feature extremely low dropout voltages, low output noise, low quiescent current (17 µA
typically), and enable inputs to reduce supply currents to 1 µA when the regulators are turned off.
The internal voltage reference is a key source of noise in a LDO regulator. The TPS789xx has a BYPASS pin
which is connected to the voltage reference through a 150-kΩ internal resistor. The 150-kΩ internal resistor,
in conjunction with an external bypass capacitor connected to the BYPASS pin, creates a low pass filter to
reduce the voltage reference noise and, therefore, the noise at the regulator output. Note that the output will
startupslowerasthebypasscapacitanceincreasesduetotheRCtimeconstantatthebypasspinthatiscreated
by the internal 150-kΩ resistor and external capacitor.
Current limiting and thermal protection prevent damage by excessive output current and/or power dissipation.
The device switches into a constant-current mode at approximately 350 mA; further load reduces the output
voltage instead of increasing the output current. The thermal protection shuts the regulator off if the junction
temperature rises above approximately 165°C. Recovery is automatic when the junction temperature drops
approximately 25°C below the high temperature trip point. The PMOS pass element includes a back gate diode
that conducts reverse current when the input voltage level drops below the output voltage level.
A voltage of 1.7 V or greater on the EN input will disable the TPS789xx internal circuitry, reducing the supply
current to 1 µA. A voltage of less than 0.9 V on the EN input will enable the TPS789xx and will enable normal
operation to resume. The EN input does not include any deliberate hysteresis, and it exhibits an actual switching
threshold of approximately 1.5 V.
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)
Input voltage range
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to 13.5 V
Voltage range at EN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to V + 0.3 V
I
Voltage on OUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 V
Peak output current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Internally limited
ESD rating, HBM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 kV
Continuous total power dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . See Dissipation Rating Table
Operating virtual junction temperature range, T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –40°C to 150°C
J
Storage temperature range, T
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –65°C to 150°C
stg
†
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.
NOTE 1: All voltage values are with respect to network ground terminal.
DISSIPATION RATING TABLE
DERATING FACTOR
T
A
≤ 25°C
T
A
= 70°C
T = 85°C
A
BOARD
PACKAGE
R
R
θJA
θJC
ABOVE T = 25°C
POWER RATING POWER RATING POWER RATING
A
‡
Low K
DBV
DBV
65.8 °C/W
65.8 °C/W
259 °C/W
180 °C/W
3.9 mW/°C
5.6 mW/°C
386 mW
555 mW
212 mW
305 mW
154 mW
222 mW
§
High K
‡
§
The JEDEC Low K (1s) board design used to derive this data was a 3 inch x 3 inch, two layer board with 2 ounce copper traces on top of the board.
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 top and bottom of the board.
3
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
TPS78915, TPS78918, TPS78925, TPS78928, TPS78930
ULTRALOW-POWER LOW-NOISE 100-mA
LOW-DROPOUT LINEAR REGULATORS
SLVS300A – SEPTEMBER 2000 – REVISED MAY 2001
recommended operating conditions
MIN NOM
MAX
10
UNIT
V
Input voltage, V (see Note 2)
2.7
0
I
Continuous output current, I (see Note 3)
100
125
mA
°C
O
Operating junction temperature, T
–40
J
NOTES: 2. To calculate the minimum input voltage for your maximum output current, use the following formula:
V (min) = V (max) + V (max load)
I
O
DO
3. Continuous output current and operating junction temperature are limited by internal protection circuitry, but it is not recommended
that the device operate under conditions beyond those specified in this table for extended periods of time.
electrical characteristics over recommended operating free-air temperature range,
V = V
+ 1 V, I = 1 mA, EN = 0 V, C = 4.7 µF (unless otherwise noted)
I
O(typ)
O
o
PARAMETER
TEST CONDITIONS
2.7 V < V < 10 V
MIN
1.455
1.746
2.425
2.716
2.910
TYP
MAX
1.545
1.854
2.575
2.884
3.090
UNIT
T
J
T
J
T
J
T
J
T
J
T
J
T
J
T
J
T
J
T
J
= 25°C,
1.5
I
TPS78915
TPS78918
TPS78925
TPS78928
TPS78930
= –40°C to 125°C, 2.7 V < V < 10 V
I
= 25°C,
2.8 V < V < 10 V
1.8
2.5
2.8
3
I
= –40°C to 125°C, 2.8 V < V < 10 V
I
= 25°C,
3.5 V < V < 10 V
I
Output voltage (see Note 4)
V
= –40°C to 125°C, 3.5 V < V < 10 V
I
= 25°C,
3.8 V < V < 10 V
I
= –40°C to 125°C, 3.8 V < V < 10 V
I
= 25°C,
4.0 V < V < 10 V
I
= –40°C to 125°C, 4.0 V < V < 10 V
I
EN = 0 V,
= 25°C
10 µA < I < 100 mA,
O
17
T
J
Quiescent current (GND current) (see Notes 4 and 5)
Load regulation
µA
mV
%/V
EN = 0 V,
= –40°C to 125°C
I
I
= 100 mA,
= See Note 4
= 25°C,
O
O
28
T
J
EN = 0 V,
= 25°C
12
T
J
V
+ 1 V < V ≤ 10 V, T
I J
O
0.04
See Note 4
Output voltage line regulation (∆V /V
) (see Note 5)
O
O
V
+ 1 V < V ≤ 10 V,
= –40°C to 125°C, See Note 4
O
I
0.1
T
J
BW = 300 Hz to 50 kHz, C
= 0.01 µF
(byp)
= 100 mA, T = 25°C
J
Output noise voltage (TPS78930)
Output current limit
56
µV
RMS
C
= 10 µF,
I
O
o
V
= 0 V,
See Note 4
2.7 < V < 10 V
350
1
750
2
mA
µA
µA
O
EN = V ,
I
I
Standby current
T
J
= –40°C to 125°C
NOTES: 4. The minimum IN operating voltage is 2.7 V or V
+ 1 V, whichever is greater. The maximum IN voltage is 10 V. The minimum
output current is 10 µA and the maximum output current is 100 mA.
O(typ)
5. If V ≤ 1.8 V then V
= 2.7 V, V
= 10 V:
O
Imin
Imax
V
V
2.7 V
O
Imax
100
Line Reg. (mV)
% V
1000
If V ≥ 2.5 V then V
= V + 1 V, V
= 10 V:
O
Imin
O
Imax
V
V
V
1 V
O
Imax
O
Line Reg. (mV)
% V
1000
100
4
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
TPS78915, TPS78918, TPS78925, TPS78928, TPS78930
ULTRALOW-POWER LOW-NOISE 100-mA
LOW-DROPOUT LINEAR REGULATORS
SLVS300A – SEPTEMBER 2000 – REVISED MAY 2001
electrical characteristics over recommended operating free-air temperature range,
V = V
+ 1 V, I = 1 mA, EN = 0 V, C = 4.7 µF (unless otherwise noted) (continued)
I
O(typ)
O
o
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
V
High level enable input voltage
Low level enable input voltage
2.7 V < V < 10 V
1.7
I
2.7 V < V < 10 V
I
0.9
V
f = 1 kHz,
C
C
= 10 µF,
o
(byp)
Power supply ripple rejection (TPS78930)
Input current (EN)
85
0
dB
T
J
= 25°C,
= 0.01 µF
EN = 0 V
EN = V
–1
–1
1
1
µA
µA
I
I
O
I
O
I
O
I
O
I
O
I
O
I
O
I
O
= 50 mA,
= 50 mA,
= 100 mA,
= 100 mA,
= 50 mA,
= 50 mA,
= 100 mA,
= 100 mA,
T
J
T
J
T
J
T
J
T
J
T
J
T
J
T
J
= 25°C
60
122
57
= –40°C to 125°C
= 25°C
125
245
115
230
TPS78928
TPS78930
= –40°C to 125°C
= 25°C
Dropout voltage (see Note 6)
mV
= –40°C to 125°C
= 25°C
115
= –40°C to 125°C
NOTE 6. IN voltage equals V (typ) – 100 mV; The TPS78930 output voltage is set to 2.9 V. The TPS78915, TPS78918, and TPS78925 dropout
O
voltage is limited by the input voltage range limitations.
TYPICAL CHARACTERISTICS
Table of Graphs
FIGURE
vs Output current
vs Junction temperature
vs Junction temperature
vs Frequency
1, 2, 3
4, 5, 6
7
V
Output voltage
O
Ground current
Output spectral noise density
Root mean squared output noise
Output impedance
8 – 10
11
vs Bypass capacitance
vs Frequency
Z
o
12
V
Dropout voltage
vs Junction temperature
vs Frequency
13
DO
O
Ripple rejection
14 – 16
17 – 19
20, 22
21, 23
24, 25
V
Output voltage, enable voltage
Line transient response
Load transient response
Equivalent series resistance (ESR)
vs Time (start-up)
vs Output current
5
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
TPS78915, TPS78918, TPS78925, TPS78928, TPS78930
ULTRALOW-POWER LOW-NOISE 100-mA
LOW-DROPOUT LINEAR REGULATORS
SLVS300A – SEPTEMBER 2000 – REVISED MAY 2001
TYPICAL CHARACTERISTICS
TPS78925
TPS78915
OUTPUT VOLTAGE
vs
OUTPUT VOLTAGE
vs
OUTPUT CURRENT
OUTPUT CURRENT
1.515
1.510
1.505
1.500
1.495
2.515
2.510
2.505
2.500
2.495
V = 2.7 V
I
V = 3.5 V
I
C
= 4.7 µF
= 25° C
o
J
C
= 4.7 µF
= 25° C
o
J
T
T
1.490
1.485
2.490
2.485
0
20
40
60
80
100
0
20
40
60
80
100
I
O
– Output Current – mA
I
O
– Output Current – mA
Figure 1
Figure 2
TPS78915
TPS78930
OUTPUT VOLTAGE
vs
OUTPUT VOLTAGE
vs
JUNCTION TEMPERATURE
OUTPUT CURRENT
3.015
3.010
3.005
1.515
1.510
1.505
1.500
1.495
1.490
V = 2.7 V
I
o
V = 4.0 V
I
C
= 4.7 µF
C
= 4.7 µF
= 25° C
o
J
T
I
O
= 1 mA
3.000
2.995
I
O
= 100 mA
2.990
2.985
1.480
0
20
40
60
80
100
–40 –25 –10
5
20 35 50 65 80
110 125
95
I
O
– Output Current – mA
T
J
– Junction Temperature – °C
Figure 3
Figure 4
6
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
TPS78915, TPS78918, TPS78925, TPS78928, TPS78930
ULTRALOW-POWER LOW-NOISE 100-mA
LOW-DROPOUT LINEAR REGULATORS
SLVS300A – SEPTEMBER 2000 – REVISED MAY 2001
TYPICAL CHARACTERISTICS
TPS78925
TPS78930
OUTPUT VOLTAGE
vs
OUTPUT VOLTAGE
vs
JUNCTION TEMPERATURE
JUNCTION TEMPERATURE
2.515
2.510
3.015
3.010
V = 3.5 V
V = 4 V
I
I
C
= 4.7 µF
C
= 4.7 µF
o
o
I
O
= 1 mA
2.505
3.005
I
O
= 1 mA
2.500
2.495
3.000
2.995
2.990
2.985
I
= 100 mA
O
I
= 100 mA
O
2.490
2.485
–40 –25 –10
5
20 35 50 65 80
110 125
–40 –25 –10
5
20 35 50 65 80
110 125
95
95
T
J
– Junction Temperature – °C
T
J
– Junction Temperature – °C
Figure 5
Figure 6
TPS78930
GROUND CURRENT
vs
TPS78930
OUTPUT SPECTRAL NOISE DENSITY
vs
JUNCTION TEMPERATURE
FREQUENCY
21
1200
1000
800
V = 4 V
I
o
(byp)
V = 4 V
I
C
C
= 4.7 µF
C
= 4.7 µF
o
20
19
18
17
16
15
14
= 0.1 µF
I
O
= 100 mA
I
= 1 mA
O
600
I
O
= 100 mA
400
I
O
= 1 mA
200
0
–40 –25 –10
5
20 35 50 65 80
110 125
95
100
1k
10k
100k
T
J
– Junction Temperature – °C
f – Frequency – Hz
Figure 7
Figure 8
7
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
TPS78915, TPS78918, TPS78925, TPS78928, TPS78930
ULTRALOW-POWER LOW-NOISE 100-mA
LOW-DROPOUT LINEAR REGULATORS
SLVS300A – SEPTEMBER 2000 – REVISED MAY 2001
TYPICAL CHARACTERISTICS
TPS78930
TPS78930
OUTPUT SPECTRAL NOISE DENSITY
OUTPUT SPECTRAL NOISE DENSITY
vs
vs
FREQUENCY
FREQUENCY
800
2
1.8
1.6
V = 4 V
I
O
V = 4 V
I
I
= 100 mA
C
C
= 10 µF
700
600
o
C = 10 µF
o
= 0.1 µF
(byp)
1.4
1.2
1
C
= 0.001 µF
(byp)
500
400
300
C
= 0.01 µF
(byp)
I
O
= 100 mA
0.8
0.6
0.4
0.2
0
I
= 1 mA
O
200
100
0
V = 4.3 V
I
C
= 0.1 µF
(byp)
100
1k
10k
100k
100
1k
10k
100k
f – Frequency – Hz
f – Frequency – Hz
Figure 9
Figure 10
OUTPUT IMPEDANCE
vs
ROOT MEAN SQUARED OUTPUT NOISE
vs
FREQUENCY
BYPASS CAPACITANCE
2
1.8
1.6
300
250
200
150
100
50
V = 4 V
I
C
= 4.7 µF
o
1.4
1.2
1
0.8
V
= 3 V
O
0.6
0.4
0.2
0
I
O
= 1 mA
I
O
= 100 mA
V
O
= 1.5 V
0
0.00001 0.0001
0.001
0.01
0.1
1
10
100
1 k
10 k
100 k
1 M
C
– Bypass Capacitance – µF
f – Frequency – Hz
(bypass)
Figure 11
Figure 12
8
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
TPS78915, TPS78918, TPS78925, TPS78928, TPS78930
ULTRALOW-POWER LOW-NOISE 100-mA
LOW-DROPOUT LINEAR REGULATORS
SLVS300A – SEPTEMBER 2000 – REVISED MAY 2001
TYPICAL CHARACTERISTICS
TPS78930
TPS78930
DROPOUT VOLTAGE
vs
RIPPLE REJECTION
vs
JUNCTION TEMPERATURE
FREQUENCY
120
135
125
115
105
95
V = 4 V
I
V = 2.9 V,
I
I
O
= 100 mA
C
C
= 10 µF
110
100
90
o
C
= 4.7 µF
o
= 0.1 µF
(byp)
I
O
= 1 mA
85
80
75
70
60
50
40
65
55
45
35
I
O
= 100 mA
25
30
20
I
= 1 mA
15
O
5
10
100
1 k
10 k
100 k
1 M
–40 –25 –10
5
20 35 50 65 80 95 110 125
T
J
– Junction Temperature – °C
f – Frequency – Hz
Figure 13
Figure 14
TPS78930
RIPPLE REJECTION
vs
TPS78930
RIPPLE REJECTION
vs
FREQUENCY
FREQUENCY
100
120
V = 4 V
I
90
I
= 1 mA
110
100
90
C
C
= 10 µF
o
(byp)
O
= 0.001 µF
80
70
60
50
I
O
= 1 mA
80
70
60
50
40
I
O
= 100 mA
40
30
20
I
O
= 100 mA
V = 4 V
I
C
C
= 10 µF
o
10
0
30
20
= 0.01 µF
(byp)
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 15
Figure 16
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TPS78915, TPS78918, TPS78925, TPS78928, TPS78930
ULTRALOW-POWER LOW-NOISE 100-mA
LOW-DROPOUT LINEAR REGULATORS
SLVS300A – SEPTEMBER 2000 – REVISED MAY 2001
TYPICAL CHARACTERISTICS
TPS78930
OUTPUT VOLTAGE, ENABLE VOLTAGE
vs
TIME (START-UP)
5
0
3
2
V = 4 V
I
O
O
V
I
= 3 V
= 100 mA
1
0
C
C
= 0.01 µF
(byp)
o
J
= 10 µF
= 25°C
T
0
1
2
3
4
5
6
7
8
9
10
t – Time – ms
Figure 17
TPS78930
TPS78930
OUTPUT VOLTAGE, ENABLE VOLTAGE
OUTPUT VOLTAGE, ENABLE VOLTAGE
vs
vs
TIME (START-UP)
TIME (START-UP)
5
0
5
0
C
= 0.001 µF
(byp)
C
= 0.1 µF
(byp)
3
2
1
0
3
2
1
0
C
= 0.01 µF
(byp)
V = 4 V
I
V
I
C
C
T
= 3 V
= 100 mA
= 0.001 µF
(byp)
= 10 µF
V = 4 V
O
O
I
O
O
V
I
= 3 V
= 100 mA
= 10 µF
= 25°C
C
T
o
J
o
J
= 25°C
0
0.2 0.4 0.6 0.8
1
1.2 1.4 1.6 1.8
2
0
10 20 30 40 50 60 70 80
90 100
t – Time – ms
t – Time – ms
Figure 18
Figure 19
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TPS78915, TPS78918, TPS78925, TPS78928, TPS78930
ULTRALOW-POWER LOW-NOISE 100-mA
LOW-DROPOUT LINEAR REGULATORS
SLVS300A – SEPTEMBER 2000 – REVISED MAY 2001
TYPICAL CHARACTERISTICS
TPS78915
TPS78915
LOAD TRANSIENT RESPONSE
LINE TRANSIENT RESPONSE
100
0
20
0
–20
3.7
0
–200
–400
2.7
V = 2.7 V
I
I
C
= 10 mA
O
C
= 10 µF
o
= 4.7 µF
o
0
20 40 60 80 100 120 140 160 180 200
0
20 40 60 80 100 120 140 160 180 200
t – Time – µs
t – Time – µs
Figure 20
Figure 21
TPS78930
TPS78930
LINE TRANSIENT RESPONSE
LOAD TRANSIENT RESPONSE
I
C
= 10 mA
= 4.7 µF
o
O
100
0
5
4.5
4
100
0
20
0
–100
–200
V = 4 V
I
o
–20
C
= 4.7 µF
0
20 40 60 80 100 120 140 160 180 200
0
20 40 60 80 100 120 140 160 180 200
t – Time – µs
t – Time – µs
Figure 22
Figure 23
11
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TPS78915, TPS78918, TPS78925, TPS78928, TPS78930
ULTRALOW-POWER LOW-NOISE 100-mA
LOW-DROPOUT LINEAR REGULATORS
SLVS300A – SEPTEMBER 2000 – REVISED MAY 2001
TYPICAL CHARACTERISTICS
TPS78930
TPS78930
TYPICAL REGIONS OF STABILITY
EQUIVALENT SERIES RESISTANCE (ESR)
vs
TYPICAL REGIONS OF STABILITY
EQUIVALENT SERIES RESISTANCE (ESR)
vs
OUTPUT CURRENT
OUTPUT CURRENT
100
100
10
V
V
C
= 4 V
= 3 V
= 4.7 µF
V
V
C
= 4 V
= 3 V
= 10 µF
IN
O
o
IN
O
o
Region of Instability
Region of Instability
Region of Stability
10
1
1
Region of Stability
0.1
0.1
0
25
50
75
100
0
25
50
75
100
I
O
– Output Current – mA
I
O
– Output Current – mA
Figure 24
Figure 25
12
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TPS78915, TPS78918, TPS78925, TPS78928, TPS78930
ULTRALOW-POWER LOW-NOISE 100-mA
LOW-DROPOUT LINEAR REGULATORS
SLVS300A – SEPTEMBER 2000 – REVISED MAY 2001
APPLICATION INFORMATION
The TPS789xx family of low-dropout (LDO) regulators have been optimized for use in battery-operated
equipment. They feature extremely low dropout voltages, low output noise, low quiescent current (17 µA
typically), and enable inputs to reduce supply currents to 1 µA when the regulators are turned off.
A typical application circuit is shown in Figure 26.
TPS789xx
1
V
I
IN
4
5
BYPASS
OUT
V
O
3
1 µF
.01 µF
EN
+
4.7 µF
GND
2
ESR = 0.2 Ω
Figure 26. Typical Application Circuit
external capacitor requirements
Although not required, a 0.047-µF or larger ceramic input bypass capacitor, connected between IN and GND
and located close to the TPS789xx, is recommended to improve transient response and noise rejection. A
higher-value electrolytic 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.
Like all low dropout regulators, the TPS789xx requires an output capacitor connected between OUT and GND
to stabilize the internal control loop. The minimum recommended capacitance is 4.7 µF. The ESR (equivalent
series resistance) of the capacitor should be between 0.2Ω and 10 Ω. toensurestability. Capacitorvalueslarger
than 4.7 µF are acceptable, and allow the use of smaller ESR values. Capacitances less than 4.7 µF are not
recommended because they require careful selection of ESR to ensure stability. Solid tantalum electrolytic,
aluminum electrolytic, and multilayer ceramic capacitors are all suitable, provided they meet the requirements
described above. Most of the commercially available 4.7 µF surface-mount solid tantalum capacitors, including
devices from Sprague, Kemet, and Nichico, meet the ESR requirements stated above. Multilayer ceramic
capacitors may have very small equivalent series resistances and may thus require the addition of a low value
series resistor to ensure stability.
CAPACITOR SELECTION
†
†
PART NO.
T494B475K016AS
195D106x0016x2T
695D106x003562T
TPSC475K035R0600
MFR.
KEMET
SPRAGUE
SPRAGUE
AVX
VALUE
4.7 µF
10 µF
MAX ESR
SIZE (H × L × W)
1.9 × 3.5 × 2.8
1.3 × 7.0 × 2.7
2.5 × 7.6 × 2.5
2.6 × 6.0 × 3.2
1.5 Ω
1.5 Ω
1.3 Ω
0.6 Ω
10 µF
4.7 µF
†
Size is in mm. The ESR maximum resistance is in ohms at 100 kHz and T = 25°C. Contact the
manufacturer for the minimum ESR values.
A
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TPS78915, TPS78918, TPS78925, TPS78928, TPS78930
ULTRALOW-POWER LOW-NOISE 100-mA
LOW-DROPOUT LINEAR REGULATORS
SLVS300A – SEPTEMBER 2000 – REVISED MAY 2001
APPLICATION INFORMATION
external capacitor requirements (continued)
The external bypass capacitor, used in conjunction with an internal resistor to form a low-pass filter, should be
a low ESR ceramic capacitor. For example, the TPS78930 exhibits only 56 µV
of output voltage noise using
RMS
a 0.01 µF ceramic bypass capacitor and a10 µF ceramic output capacitors. Note that the output will start up
slower as the bypass capacitance increases due to the RC time constant at the bypass pin that is created by
the internal 150 kΩ resistor and external capacitor.
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, P
, and the actual dissipation, P , which must be less than
D(max)
D
or equal to P
.
D(max)
The maximum-power-dissipation limit is determined using the following equation:
T max
J
T
A
P
D(max)
R
JA
Where:
T max is the maximum allowable junction temperature.
J
R
is the thermal resistance junction-to-ambient for the package, see the dissipation rating table.
θJA
T is the ambient temperature.
A
The regulator dissipation is calculated using:
P
V
V
I
D
I
O
O
Power dissipation resulting from quiescent current is negligible. Excessive power dissipation will trigger the
thermal protection circuit.
regulator protection
The TPS789xx PMOS-pass transistor has a built-in back diode that conducts reverse current when the input
voltage drops below the output voltage (e.g., 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 might
be appropriate.
The TPS789xx features internal current limiting and thermal protection. During normal operation, the TPS789xx
limits output current to approximately 350 mA. 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 thedevice
exceeds approximately 165°C, thermal-protection circuitry shuts it down. Once the device has cooled down to
below approximately 140°C, regulator operation resumes.
14
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TPS78915, TPS78918, TPS78925, TPS78928, TPS78930
ULTRALOW-POWER LOW-NOISE 100-mA
LOW-DROPOUT LINEAR REGULATORS
SLVS300A – SEPTEMBER 2000 – REVISED MAY 2001
MECHANICAL DATA
DBV (R-PDSO-G5)
PLASTIC SMALL-OUTLINE
0,50
0,30
M
0,20
0,95
5
4
0,15 NOM
1,70
1,50
3,00
2,60
1
3
Gage Plane
3,00
2,80
0,25
0°–8°
0,55
0,35
Seating Plane
0,10
1,45
0,95
0,05 MIN
4073253-4/F 10/00
NOTES: A. All linear dimensions are in millimeters.
B. This drawing is subject to change without notice.
C. Body dimensions do not include mold flash or protrusion.
D. Falls within JEDEC MO-178
15
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