ADP7142 Datasheet by Analog Devices Inc.

ANALOG DEVICES H4:
40 V, 200 mA, Low Noise,
CMOS LDO Linear Regulator
Data Sheet ADP7142
Rev. H Document Feedback
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FEATURES
Low noise: 11 µV rms independent of fixed output voltage
PSRR of 88 dB at 10 kHz, 68 dB at 100 kHz, 50 dB at 1 MHz,
VOUT ≤ 5 V, VIN = 7 V
Input voltage range: 2.7 V to 40 V
Maximum output current: 200 mA
Initial accuracy: ±0.8%
Accuracy over line, load, and temperature
−1.2% to +1.5%, TJ = −40°C to +85°C
±1.8%, TJ = −40°C to +125°C
Low dropout voltage: 200 mV (typical) at a 200 mA load,
VOUT = 5 V
User programmable soft start (LFCSP and SOIC only)
Low quiescent current, IGND = 50 A (typical) with no load
Low shutdown current: 1.8A at VIN = 5 V, 3.0 A at VIN = 40 V
Stable with a small 2.2 µF ceramic output capacitor
Fixed output voltage options: 1.8 V, 2.5 V, 3.3 V, 3.8 V, and 5.0 V
15 standard voltages between 1.2 V and 5.0 V are
available
Adjustable output from 1.2 V to VIN – VDO, output can be
adjusted above initial set point
Precision enable
2 mm × 2 mm, 6-lead LFCSP, 8-Lead SOIC, 5-Lead TSOT
Supported by ADIsimPower tool
APPLICATIONS
Regulation to noise sensitive applications
ADC, DAC circuits, precision amplifiers, power for
VCO VTUNE control
Communications and infrastructure
Medical and healthcare
Industrial and instrumentation
TYPICAL APPLICATION CIRCUITS
GND
EN SS
VIN VOUT
ADP7142
ON
OFF
V
IN
= 6V V
OUT
= 5V
SENSE/ADJ
C
IN
2.2µF
C
OUT
2.2µF
C
SS
1nF
11848-001
Figure 1. ADP7142 with Fixed Output Voltage, 5 V
GND
EN SS
VIN VOUT
ADP7142
ON
OFF
V
IN
= 7V V
OUT
= 6V
SENSE/ADJ
C
IN
2.2µF
C
OUT
2.2µF
C
SS
1nF
2kΩ
10kΩ
11848-002
Figure 2. ADP7142 with 5 V Output Adjusted to 6 V
GENERAL DESCRIPTION
The ADP7142 is a CMOS, low dropout (LDO) linear regulator
that operates from 2.7 V to 40 V and provides up to 200 mA of
output current. This high input voltage LDO is ideal for the
regulation of high performance analog and mixed signal
circuits operating from 39 V down to 1.2 V rails. Using an
advanced proprietary architecture, the device provides high
power supply rejection, low noise, and achieves excellent line and
load transient response with a small 2.2 µF ceramic output
capacitor. The ADP7142 regulator output noise is 11 V rms
independent of the output voltage for the fixed options of 5 V
or less.
The ADP7142 is available in 15 fixed output voltage options.
The following voltages are available from stock: 1.2 V
(adjustable), 1.8 V, 2.5 V, 3.3 V, 3.8 V, and 5.0 V. Additional
voltages available by special order are 1.5 V, 1.85 V, 2.0 V, 2.2 V,
2.75 V, 2.8 V, 2.85 V, 4.2 V, and 4.6 V.
Each fixed output voltage can be adjusted above the initial set
point with an external feedback divider. This allows the ADP7142
to provide an output voltage from 1.2 V to VIN − VDO with high
PSRR and low noise.
User programmable soft start with an external capacitor is
available in the LFCSP and SOIC packages.
The ADP7142 is available in a 6-lead, 2 mm × 2 mm LFCSP
making it not only a very compact solution, but it also provides
excellent thermal performance for applications requiring up to
200 mA of output current in a small, low profile footprint. The
ADP7142 is also available in a 5-lead TSOT and an 8-lead SOIC.
ADP7142 Data Sheet
Rev. H | Page 2 of 23
TABLE OF CONTENTS
Features .............................................................................................. 1
Applications ...................................................................................... 1
Typical Application Circuits ........................................................... 1
General Description ......................................................................... 1
Revision History ............................................................................... 2
Specifications .................................................................................... 3
Input and Output Capacitance, Recommended Specifications .. 4
Absolute Maximum Ratings ........................................................... 5
Thermal Data ................................................................................ 5
Thermal Resistance ...................................................................... 5
ESD Caution.................................................................................. 5
Pin Configurations and Function Descriptions ........................... 6
Typical Performance Characteristics ............................................. 7
Theory of Operation ...................................................................... 13
Applications Information ............................................................. 14
ADIsimPower Design Tool ...................................................... 14
Capacitor Selection .................................................................... 14
Programable Precision Enable ................................................. 15
Soft Start ...................................................................................... 15
Noise Reduction of the ADP7142 in Adjustable Mode ........ 16
Effect of Noise Reduction on Start-Up Time ......................... 16
Current-Limit and Thermal Overload Protection ................ 17
Thermal Considerations ........................................................... 17
Printed Circuit Board Layout Considerations ........................... 20
Outline Dimensions ....................................................................... 22
Ordering Guide .......................................................................... 23
REVISION HISTORY
3/2020—Rev. G to Rev. H
Changes to General Description Section ...................................... 1
Changes to Shutdown Current Parameter, Table 1 ..................... 3
Changes to Theory of Operation Section .................................... 13
Change to Figure 50 ....................................................................... 16
Changes to Current-Limit and Thermal Overload
Protection Section .......................................................................... 17
Changes to Table 8 and Table 9.................................................... 21
10/2019—Rev. F to Rev. G
Changes to Features Section and General Description Section ....... 1
Changes to Ordering Guide .......................................................... 23
9/2018—Rev. E to Rev. F
Changes to Ordering Guide .......................................................... 23
4/2018—Rev. D to Rev. E
Changes to Features Section ........................................................... 1
Changes to Ordering Guide .......................................................... 23
11/2017—Rev. C to Rev. D
Changes to Ordering Guide .......................................................... 22
Updated Outline Dimensions ...................................................... 23
6/2016—Rev. B to Rev. C
Changes to Figure 42 ..................................................................... 13
Changes to Programmable Precision Enable Section and Soft
Start Section .................................................................................... 15
Changes to Figure 50 ..................................................................... 16
Added Effect of Noise Reduction on Start-Up Time Section .. 16
4/2015—Rev. A to Rev. B
Changes to Ordering Guide .......................................................... 23
12/2014—Rev. 0 to Rev. A
Changes to Figure 36 to Figure 41 ............................................... 12
Changes to Figure 44 ..................................................................... 14
Updated Figure 67; Outline Dimensions .................................... 22
9/2014—Revision 0: Initial Version
Data Sheet ADP7142
Rev. H | Page 3 of 23
SPECIFICATIONS
VIN = VOUT +1 V or 2.7 V, whichever is greater, VOUT = 5 V, EN = VIN, IOUT = 10 mA, CIN = COUT = 2.2 µF, CSS = 0 pF, TA = 25°C for typical
specifications, TJ = −40°C to +125°C for minimum/maximum specifications, unless otherwise noted.
Table 1.
Parameter Symbol Test Conditions/Comments Min Typ Max Unit
INPUT VOLTAGE RANGE VIN 2.7 40 V
OPERATING SUPPLY CURRENT IGND I
OUT = 0 µA 50 140 µA
I
OUT = 10 mA 80 190 µA
I
OUT = 200 mA 180 320 µA
SHUTDOWN CURRENT IGND-SD EN = GND 1.8 µA
EN = GND, VIN = 40 V 3.0 10 µA
OUTPUT VOLTAGE ACCURACY
Output Voltage Accuracy VOUT I
OUT = 10 mA, TJ = 25°C –0.8 +0.8 %
100 A < IOUT < 200 mA, VIN = (VOUT + 1 V) to 40 V,
TJ = −40°C to +85°C
–1.2 +1.5 %
100 A < IOUT < 200 mA, VIN = (VOUT + 1 V) to 40 V –1.8 +1.8 %
LINE REGULATION VOUT/VIN V
IN = (VOUT + 1 V) to 40 V –0.01 +0.01 %/V
LOAD REGULATION1 VOUT/IOUT I
OUT = 100 A to 200 mA 0.002 0.004 %/mA
SENSE INPUT BIAS CURRENT SENSEI-BIAS 100 A < IOUT < 200 mA VIN = (VOUT + 1 V) to 40 V 10 1000 nA
DROPOUT VOLTAGE2 V
DROPOUT I
OUT = 10 mA 30 60 mV
I
OUT = 200 mA 200 420 mV
START-UP TIME3 t
START-UP V
OUT = 5 V 380 µs
SOFT START SOURCE CURRENT SSI-SOURCE SS = GND 1.15 µA
CURRENT-LIMIT THRESHOLD4 I
LIMIT 250 360 460 mA
THERMAL SHUTDOWN
Thermal Shutdown Threshold TSSD T
J rising 150 °C
Thermal Shutdown Hysteresis TSSD-HYS 15 °C
UNDERVOLTAGE THRESHOLDS
Input Voltage Rising UVLORISE 2.69 V
Input Voltage Falling UVLOFALL 2.2 V
Hysteresis UVLOHYS 230 mV
PRECISION EN INPUT 2.7 V ≤ VIN ≤ 40 V
Logic High ENHIGH 1.15 1.22 1.30 V
Logic Low ENLOW 1.06 1.12 1.18 V
Logic Hysteresis ENHYS 100 mV
Leakage Current IEN-LKG EN = VIN or GND 0.04 1 µA
Delay Time tEN-DLY From EN rising from 0 V to VIN to 0.1 × VOUT 80 s
OUTPUT NOISE OUTNOISE 10 Hz to 100 kHz, all output voltage options 11 µV rms
POWER SUPPLY REJECTION RATIO PSRR 1 MHz, VIN = 7 V, VOUT = 5 V 50 dB
100 kHz, VIN = 7 V, VOUT = 5 V 68 dB
10 kHz, VIN = 7 V, VOUT = 5 V 88 dB
1 Based on an endpoint calculation using 100 A and 200 mA loads. See Figure 7 for typical load regulation performance for loads less than 1 mA.
2 Dropout voltage is defined as the input-to-output voltage differential when the input voltage is set to the nominal output voltage. Dropout applies only for output
voltages above 2.7 V.
3 Start-up time is defined as the time between the rising edge of EN to OUT being at 90% of its nominal value.
4 Current-limit threshold is defined as the current at which the output voltage drops to 90% of the specified typical value. For example, the current limit for a 5.0 V
output voltage is defined as the current that causes the output voltage to drop to 90% of 5.0 V or 4.5 V.
ADP7142 Data Sheet
Rev. H | Page 4 of 23
INPUT AND OUTPUT CAPACITANCE, RECOMMENDED SPECIFICATIONS
Table 2.
Parameter Symbol Test Conditions/Comments Min Typ Max Unit
INPUT AND OUTPUT CAPACITANCE
Minimum Capacitance1 C
MIN T
A = −40°C to +125°C 1.5 µF
Capacitor Effective Series Resistance (ESR) RESR T
A = −40°C to +125°C 0.001 0.3 Ω
1 The minimum input and output capacitance must be greater than 1.5 F over the full range of operating conditions. The full range of operating conditions in the
application must be considered during device selection to ensure that the minimum capacitance specification is met. X7R and X5R type capacitors are recommended,
while Y5V and Z5U capacitors are not recommended for use with any LDO.
m ESD (electrostatic discharge) sensitive devize. Charged dame; and (mm! board: an mschayge wimoux dexemon Ahhough m: pvodun reaxuves mama m pmpnflavy pvmenmn (mum, damage may om" on dewex subjeued \o mgh enevgy ESD. Thevefave, plopev ESD pvecauhon: shou‘d be ‘aken m mm pefiovmance degvadauon 0v losx oi mncncnalwy.
Data Sheet ADP7142
Rev. H | Page 5 of 23
ABSOLUTE MAXIMUM RATINGS
Table 3.
Parameter Rating
VIN to GND –0.3 V to +44 V
VOUT to GND –0.3 V to VIN
EN to GND –0.3 V to +44 V
SENSE/ADJ to GND –0.3 V to +6 V
SS to GND –0.3 V to VIN or +6 V
(whichever is less)
Storage Temperature Range –65°C to +150°C
Junction Temperature (TJ) 150°C
Operating Ambient Temperature
(TA) Range
–40°C to +125°C
Soldering Conditions JEDEC J-STD-020
Stresses at or above those listed under Absolute Maximum
Ratings may cause permanent damage to the product. This is a
stress rating only; functional operation of the product at these
or any other conditions above those indicated in the
operational section of this specification is not implied.
Operation beyond the maximum operating conditions for
extended periods may affect product reliability.
THERMAL DATA
Absolute maximum ratings apply individually only, not in
combination. The ADP7142 can be damaged when the junction
temperature limits are exceeded. Monitoring ambient temperature
does not guarantee that TJ is within the specified temperature
limits. In applications with high power dissipation and poor
thermal resistance, the maximum ambient temperature may
have to be derated.
In applications with moderate power dissipation and low printed
circuit board (PCB) thermal resistance, the maximum ambient
temperature can exceed the maximum limit as long as the
junction temperature is within specification limits. The
junction temperature of the device is dependent on the ambient
temperature, the power dissipation (PD) of the device, and the
junction-to-ambient thermal resistance of the package (θJA).
Maximum TJ is calculated from the TA and PD using the
formula
TJ = TA + (PD × θJA) (1)
θJA of the package is based on modeling and calculation using a
4-layer board. The θJA is highly dependent on the application
and board layout. In applications where high maximum power
dissipation exists, close attention to thermal board design is
required. The value of θJA may vary, depending on PCB material,
layout, and environmental conditions. The specified values of θJA
are based on a 4-layer, 4 inches × 3 inches circuit board. See
JESD51-7 and JESD51-9 for detailed information on the board
construction.
ΨJB is the junction-to-board thermal characterization parameter
with units of °C/W. The ΨJB of the package is based on
modeling and calculation using a 4-layer board. The JESD51-12,
Guidelines for Reporting and Using Electronic Package Thermal
Information, states that thermal characterization parameters are
not the same as thermal resistances. ΨJB measures the component
power flowing through multiple thermal paths rather than a
single path as in thermal resistance (θJB). Therefore, ΨJB thermal
paths include convection from the top of the package as well as
radiation from the package, factors that make ΨJB more useful
in real-world applications. Maximum TJ is calculated from the
board temperature (TB) and PD using the formula
TJ = TB + (PD × ΨJB) (2)
See JESD51-8 and JESD51-12 for more detailed information
about ΨJB.
THERMAL RESISTANCE
θJA, θJC, and ΨJB are specified for the worst-case conditions, that
is, a device soldered in a circuit board for surface-mount packages.
Table 4. Thermal Resistance
Package Type θJA θ
JC Ψ
JB Unit
6-Lead LFCSP 72.1 42.3 47.1 °C/W
8-Lead SOIC 52.7 41.5 32.7 °C/W
5-Lead TSOT 170 N/A1 43 °C/W
1 N/A means not applicable.
ESD CAUTION
ADP7142 Data Sheet
Rev. H | Page 6 of 23
PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS
3GND
1VOUT
2SENSE/ADJ
4EN
6VIN
5SS
ADP7142
TOP VIEW
(Not to Scale)
EXPOSED PAD
NOTES
1. THE EXPOSED PAD ON THE BOTTOM OF THE PACKAGE
ENHANCES THERMAL PERFORMANCE AND IS
ELECTRICALLY CONNECTED TO GND INSIDE THE
PACKAGE. IT IS RECOMMENDED THAT THE EXPOSED
PAD CONNECT TO THE GROUND PLANE ON THE BOARD.
11848-003
Figure 3. 6-Lead LFCSP Pin Configuration
11848-104
ADP7142
TOP VIEW
(Not to Scale)
1
VIN
2
GND
3
EN
5
VOUT
4
SENSE/ADJ
Figure 4. 5-Lead TSOT Pin Configuration
11848-105
ADP7142
TOP VIEW
(Not to Scale)
VOUT
1
VOUT
2
SENSE/ADJ
3
GND
4
VIN
8
VIN
7
SS
6
EN
5
NOTES
1. THE EXPOSED PAD ON THE BOTTOM OF THE PACKAGE
ENHANCES THERMAL PERFORMANCE AND IS
ELECTRICALLY CONNECTED TO GND INSIDE THE
PACKAGE. IT IS RECOMMENDED THAT THE EXPOSED
PAD CONNECT TO THE GROUND PLANE ON THE BOARD.
Figure 5. 8-Lead SOIC Pin Configuration
Table 5. Pin Function Descriptions
Pin No.
6-Lead
LFCSP
8-Lead
SOIC
5-Lead
TSOT Mnemonic Description
1 1, 2 5 VOUT Regulated Output Voltage. Bypass VOUT to GND with a 2.2 µF or greater capacitor.
2 3 4 SENSE/ADJ
Sense Input (SENSE). Connect to load. An external resistor divider may also be used to
set the output voltage higher than the fixed output voltage (ADJ).
3 4 2 GND Ground.
4 5 3 EN
The enable pin controls the operation of the LDO. Drive EN high to turn on the
regulator. Drive EN low to turn off the regulator. For automatic startup, connect
EN to VIN.
5 6
Not
applicable
SS Soft Start. An external capacitor connected to this pin determines the soft-start
time. Leave this pin open for a typical 380 s start-up time. Do not ground this pin.
6 7, 8 1 VIN Regulator Input Supply. Bypass VIN to GND with a 2.2 µF or greater capacitor.
EP
Exposed Pad. The exposed pad on the bottom of the package enhances thermal
performance and is electrically connected to GND inside the package. It is
recommended that the exposed pad connect to the ground plane on the board.
Data Sheet ADP7142
Rev. H | Page 7 of 23
TYPICAL PERFORMANCE CHARACTERISTICS
VIN = VOUT + 1 V or 2.7 V, whichever is greater, VOUT = 5 V, IOUT = 10 mA, CIN = COUT = 2.2 µF, TA = 25°C, unless otherwise noted.
–40 –5 25 85 125
V
OUT
(V)
JUNCTION TEMPERATURE (°C)
4.95
4.96
4.97
4.98
4.99
5.00
5.01
5.02
5.03
5.04
5.05 LOAD = 100µA
LOAD = 1mA
LOAD = 10mA
LOAD = 50mA
LOAD = 100mA
LOAD = 200mA
11848-004
Figure 6. Output Voltage (VOUT) vs. Junction Temperature
0.1 1 10 100 1000
V
OUT
(V)
I
LOAD
(mA)
4.95
4.96
4.97
4.98
4.99
5.00
5.01
5.02
5.03
5.04
5.05
11848-005
Figure 7. Output Voltage (VOUT) vs. Load Current (ILOAD)
5 10152025303540
V
OUT
(V)
V
IN
(V)
4.95
4.96
4.97
4.98
4.99
5.00
5.01
5.02
5.03
5.04
5.05 LOAD = 100µA
LOAD = 1mA
LOAD = 10mA
LOAD = 50mA
LOAD = 100mA
LOAD = 200mA
11848-006
Figure 8. Output Voltage (VOUT) vs. Input Voltage (VIN)
–40 –5 25 85 125
GROUND CURRENT (µA)
JUNCTION TEMPERATURE (°C)
0
50
100
150
200
250
300 LOAD = 100µA
LOAD = 1mA
LOAD = 10mA
LOAD = 50mA
LOAD = 100mA
LOAD = 200mA
11848-007
Figure 9. Ground Current vs. Junction Temperature
0.1 1 10 100 1000
GROUND CURRENT (µA)
I
LOAD
(mA)
0
20
40
60
80
100
120
140
160
180
200
11848-008
Figure 10. Ground Current vs. Load Current (ILOAD)
5 10152025303540
GROUND CURRENT (µA)
V
IN
(V)
0
50
100
150
200
250
300 LOAD = 100µA
LOAD = 1mA
LOAD = 10mA
LOAD = 50mA
LOAD = 100mA
LOAD = 200mA
11848-009
Figure 11. Ground Current vs. Input Voltage (VIN)
ADP7142 Data Sheet
Rev. H | Page 8 of 23
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0
–50 –25 0 25 50 75 100 125
SHUTDOWN CURRENT (µA)
TEMPERATURE (°C)
VIN = 2.7V
VIN = 3V
VIN = 5V
VIN = 6V
VIN = 10V
VIN = 40V
11848-010
Figure 12. Shutdown Current vs. Temperature at Various Input Voltages (VIN)
1 10 100 1000
DROPOUT (mV)
I
LOAD
(mA)
0
50
100
150
200
250
11848-011
Figure 13. Dropout Voltage vs. Load Current (ILOAD), VOUT = 5 V
4.8 5.0 5.4 5.65.2
V
OUT
(V)
V
IN
(V)
4.60
4.65
4.70
4.75
4.80
4.85
4.90
4.95
5.00
5.05
LOAD = 5mA
LOAD = 10mA
LOAD = 50mA
LOAD = 100mA
LOAD = 150mA
LOAD = 200mA
11848-012
Figure 14. Output Voltage (VOUT) vs. Input Voltage (VIN) in Dropout, VOUT = 5 V
4.85.0 5.45.65.2
GROUND CURRENT (µA)
V
IN
(V)
0
100
200
300
400
500
600
700
800
1000
900
LOAD = 5mA
LOAD = 10mA
LOAD = 50mA
LOAD = 100mA
LOAD = 150mA
LOAD = 200mA
11848-013
Figure 15. Ground Current vs. Input Voltage (VIN) in Dropout, VOUT = 5 V
–40–52585125
V
OUT
(V)
JUNCTION TEMPERATURE (°C)
3.25
3.35
3.33
3.31
3.29
3.27
LOAD = 100µA
LOAD = 1mA
LOAD = 10mA
LOAD = 50mA
LOAD = 100mA
LOAD = 200mA
11848-014
Figure 16. Output Voltage (VOUT) vs. Junction Temperature, VOUT = 3.3 V
0.1 1 10 100 1000
V
OUT
(V)
I
LOAD
(mA)
3.25
3.27
3.29
3.31
3.33
3.35
11848-015
Figure 17. Output Voltage (VOUT) vs. Load Current (ILOAD), VOUT = 3.3 V
Data Sheet ADP7142
Rev. H | Page 9 of 23
0 102030405 152535
V
OUT
(V)
V
IN
(V)
3.25
3.27
3.29
3.31
3.33
3.35 LOAD = 100µA
LOAD = 1mA
LOAD = 10mA
LOAD = 50mA
LOAD = 100mA
LOAD = 200mA
11848-016
Figure 18. Output Voltage (VOUT) vs. Input Voltage (VIN), VOUT = 3.3 V
–40 –5 25 85 125
GROUND CURRENT (µA)
JUNCTION TEMPERATURE (°C)
0
300
250
200
150
100
50
LOAD = 100µA
LOAD = 1mA
LOAD = 10mA
LOAD = 50mA
LOAD = 100mA
LOAD = 200mA
11848-017
Figure 19. Ground Current vs. Junction Temperature, VOUT = 3.3 V
0.1 1 10 100 1000
GROUND CURRENT (µA)
I
LOAD
(mA)
0
40
80
120
160
200
20
60
100
140
180
11848-018
Figure 20. Ground Current vs. Load Current (ILOAD), VOUT = 3.3 V
0 102030405152535
GROUND CURRENT (µA)
V
IN
(V)
0
300
250
200
150
100
50
LOAD = 100µA
LOAD = 1mA
LOAD = 10mA
LOAD = 50mA
LOAD = 100mA
LOAD = 200mA
11848-019
Figure 21. Ground Current vs. Input Voltage (VIN), VOUT = 3.3 V
1 10 100 1000
DROPOUT (mV)
I
LOAD
(mA)
0
50
100
150
200
300
250
11848-020
Figure 22. Dropout Voltage vs. Load Current (ILOAD), VOUT = 3.3 V
3.1 3.3 3.73.5 3.9
V
OUT
(V)
V
IN
(V)
2.8
2.9
3.0
3.1
3.2
3.4
3.3
LOAD = 5mA
LOAD = 10mA
LOAD = 50mA
LOAD = 100mA
LOAD = 150mA
LOAD = 200mA
11848-021
Figure 23. Output Voltage (VOUT) vs. Input Voltage (VIN) in Dropout,
VOUT = 3.3 V
ADP7142 Data Sheet
Rev. H | Page 10 of 23
3.1 3.3 3.73.5 3.9
GROUND CURRENT (µA)
V
IN
(V)
0
100
200
300
400
700
500
600
LOAD = 5mA
LOAD = 10mA
LOAD = 50mA
LOAD = 100mA
LOAD = 150mA
LOAD = 200mA
11848-022
Figure 24. Ground Current vs. Input Voltage (VIN) in Dropout, VOUT = 3.3 V
–40 –5 25 85 125
SS CURRENT (µA)
TEMPERATURE (°C)
0
300
250
200
150
100
50
V
IN
= 2.7V
V
IN
= 5.0V
V
IN
= 10V
V
IN
= 20V
V
IN
= 40V
11848-023
Figure 25. Soft Start (SS) Current vs. Temperature, Multiple Input Voltages (VIN),
VOUT = 5 V
110M1M100k10k1k10010
PSRR (dB)
FREQUENCY (Hz)
–100
–90
–80
–70
–60
–50
–40
–30
–20
–10
03.0V
2.0V
1.6V
1.4V
1.2V
1.0V
800mV
700mV
600mV
11848-024
Figure 26. Power Supply Rejection Ratio (PSRR) vs. Frequency, VOUT = 1.8 V,
for Various Headroom Voltages
0.2 3.02.62.21.81.41.00.6
PSRR (dB)
HEADROOM VOLTAGE (V)
–100
–90
–80
–70
–60
–50
–40
–30
–20
–10
0
10Hz
100Hz
1kHz
10kHz
100kHz
1MHz
10MHz
11848 -025
Figure 27. Power Supply Rejection Ratio (PSRR) vs. Headroom Voltage,
VOUT = 1.8 V, for Different Frequencies
10 10M1M100k10k1k100
PSRR (dB)
FREQUENCY (Hz)
–120
–100
–80
–60
–40
–20
0
3.0V
2.0V
1.6V
1.4V
1.2V
1.0V
800mV
700mV
600mV
500mV
11848-026
Figure 28. Power Supply Rejection Ratio (PSRR) vs. Frequency, VOUT = 3.3 V,
for Various Headroom Voltages
0.40.60.81.01.21.41.61.82.02.22.42.62.83.0
PSRR (dB)
HEADROOM VOLTAGE (V)
–100
–90
–80
–70
–60
–50
–40
–30
–20
–10
010Hz
100Hz
1kHz
10kHz
100kHz
1MHz
10MHz
11848-027
Figure 29. Power Supply Rejection Ratio (PSRR) vs. Headroom Voltage,
VOUT = 3.3 V, for Different Frequencies
/ w A
Data Sheet ADP7142
Rev. H | Page 11 of 23
10 10M1M100k10k1k100
PSRR (dB)
FREQUENCY (Hz)
–120
–100
–80
–60
–40
–20
0
3.0V
2.0V
1.6V
1.4V
1.2V
1.0V
800mV
700mV
600mV
500mV
11848-028
Figure 30. Power Supply Rejection Ratio (PSRR) vs. Frequency, VOUT = 5 V,
for Various Headroom Voltages
0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 2.8 3.0
PSRR (dB)
HEADROOM VOLTAGE (V)
–100
–90
–80
–70
–60
–50
–40
–30
–20
–10
010Hz
100Hz
1kHz
10kHz
100kHz
1MHz
10MHz
11848-029
Figure 31. Power Supply Rejection Ratio (PSRR) vs. Headroom Voltage,
VOUT = 5 V, for Different Frequencies
1 10 100 1000
RMS OUTPUT NOISE (µV rms)
LOAD CURRENT (mA)
0
4
8
12
16
20 10Hz TO 100kHz
100Hz TO 100kHz
11848-030
Figure 32. RMS Output Noise vs. Load Current (ILOAD)
NOISE SPECTRAL DENSITY (nV/
√
Hz)
FREQUENCY (Hz)
10M1 10 100 1k 10k 100k 1M
1
10
100
1k
10k
11848-031
Figure 33. Output Noise Spectral Density vs. Frequency, ILOAD = 10 mA
NOISE SPECTRAL DENSITY (nV/
√
Hz)
FREQUENCY (Hz)
10M1 10 100 1k 10k 100k 1M
1
10
100
1k
10k
100k 100µA
1mA
10mA
100mA
200mA
11848-032
Figure 34. Output Noise Spectral Density vs. Frequency, for Different Loads
NOISE SPECTRAL DENSITY (nV/
√
Hz)
FREQUENCY (Hz)
10M1 10 100 1k 10k 100k 1M
1
10
100
1k
10k
100k 1.8V
3.3V
5.0V
11848-033
Figure 35. Output Noise Spectral Density vs. Frequency, for Different Output
Voltages (VOUT)
ADP7142 Data Sheet
Rev. H | Page 12 of 23
11848-034
CH1 200mA Ω
BW
CH2 20mV
BW
M20µs A CH1 1000mA
T 10.2%
1
2
T
Figure 36. Load Transient Response, ILOAD = 1 mA to 200 mA,
VOUT = 5 V, VIN = 7 V, CH1 Load Current (ILOAD), CH2 VOUT
11848-035
CH1 2V
BW
CH2 2.0mV
BW
M4µs A CH4 1.84V
T 10.2%
1
2
T
Figure 37. Line Transient Response, ILOAD = 200 mA,
VOUT = 5 V, CH1 VIN, CH2 VOUT
11848-036
CH1 200mA Ω
BW
CH2 20mV
BW
M20µs A CH1 148mA
T 10.4%
1
2
T
Figure 38. Load Transient Response, ILOAD = 1 mA to 200 mA,
VOUT = 3.3 V, VIN = 5 V, CH1 Load Current (ILOAD), CH2 VOUT
11848-037
CH1 1V
BW
CH2 2mV
BW
M4µs A CH4 1.84V
T 10.2%
1
2
T
Figure 39. Line Transient Response, ILOAD = 200 mA,
VOUT = 3.3 V, CH1 VIN, CH2 VOUT
11848-038
CH1 200mA Ω
BW
M20µs A CH1 84mA
T 10.2%
1
2
CH2 20mV
BW
T
Figure 40. Load Transient Response, ILOAD = 1 mA to 200 mA,
VOUT = 1.8 V, VIN = 3 V, CH1 Load Current (ILOAD), CH2 VOUT
11848-039
CH1 1V
BW
M4.0µs A CH4 2.08V
T 93.4%
1
2
CH2 5mV
T
Figure 41. Line Transient Response, ILOAD = 200 mA,
VOUT = 1.8 V, CH1 VIN, CH2 VOUT
«#W
Data Sheet ADP7142
Rev. H | Page 13 of 23
THEORY OF OPERATION
The ADP7142 is a low quiescent current, LDO linear regulator
that operates from 2.7 V to 40 V and provides up to 200 mA of
output current. Drawing a low 180 A of quiescent current
(typical) at full load makes the ADP7142 ideal for portable
equipment. Typical shutdown current consumption is less than
3 A at room temperature.
Optimized for use with small 2.2 µF ceramic capacitors, the
ADP7142 provides excellent transient performance.
VOUT
SENSE/
ADJ
GND
SHORT-CIRCUIT,
THERMAL
PROTECTION
REFERENCE
SHUTDOWN
EN
VIN
11848-040
Figure 42. Internal Block Diagram
Internally, the ADP7142 consists of a reference, an error amplifier,
and a PMOS pass transistor. Output current is delivered via the
PMOS pass device, which is controlled by the error amplifier. The
error amplifier compares the reference voltage with the feedback
voltage from the output and amplifies the difference. If the
feedback voltage is lower than the reference voltage, the gate of
the PMOS device is pulled lower, allowing more current to pass
and increasing the output voltage. If the feedback voltage is
higher than the reference voltage, the gate of the PMOS device
is pulled higher, allowing less current to pass and decreasing
the output voltage.
The ADP7142 is available in 15 fixed output voltage options,
ranging from 1.2 V to 5.0 V. The ADP7142 architecture allows
any fixed output voltage to be set to a higher voltage with an
external voltage divider. For example, a fixed 5 V output can be
set to a 6 V output according to the following equation:
VOUT = 5 V (1 + R1/R2) (3)
where R1 and R2 are the resistors in the output voltage divider
shown in Figure 43.
To set the output voltage of the adjustable ADP7142, replace 5 V
in Equation 3 with 1.2 V.
VOUT
SENSE/ADJ
VIN
ADP7142
GND SS C
SS
1nF
C
IN
2.2µF
C
OUT
2.2µF
EN
OFF
ON
V
IN
= 7V V
OUT
= 6V
R1
2kΩ
R2
10kΩ
11848-041
Figure 43. Typical Adjustable Output Voltage Application Schematic
It is recommended that the R2 value be less than 200 k
to minimize errors in the output voltage caused by the
SENSE/ADJ pin input current. For example, when R1 and R2
each equal 200 k and the default output voltage is 1.2 V, the
adjusted output voltage is 2.4 V. The output voltage error
introduced by the SENSE/ADJ pin input current is 1 mV or 0.04%,
assuming a typical SENSE/ ADJ pin input current of 10 nA at
25°C.
The ADP7142 uses the EN pin to enable and disable the
VOUT pin under normal operating conditions. When EN is
high, VOUT turns on, and when EN is low, VOUT turns off.
For automatic startup, EN can be tied to VIN.
ADP7142 Data Sheet
Rev. H | Page 14 of 23
APPLICATIONS INFORMATION
ADIsimPOWER DESIGN TOOL
The ADP7142 is supported by the ADIsimPower™ design tool
set. ADIsimPower is a collection of tools that produce complete
power designs optimized for a specific design goal. The tools
enable the user to generate a full schematic, bill of materials, and
calculate performance in minutes. ADIsimPower can optimize
designs for cost, area, efficiency, and parts count, taking into
consideration the operating conditions and limitations of the IC
and all real external components. For more information about,
and to obtain ADIsimPower design tools, visit
www.analog.com/ADIsimPower.
CAPACITOR SELECTION
Output Capacitor
The ADP7142 is designed for operation with small, space-saving
ceramic capacitors, but functions with general-purpose capacitors
as long as care is taken with regard to the effective series resistance
(ESR) value. The ESR of the output capacitor affects the stability
of the LDO control loop. A minimum of 2.2 µF capacitance with
an ESR of 0.3 Ω or less is recommended to ensure the stability of
the ADP7142. Transient response to changes in load current is
also affected by output capacitance. Using a larger value of output
capacitance improves the transient response of the ADP7142 to
large changes in load current. Figure 44 shows the transient
responses for an output capacitance value of 2.2 µF.
11848-042
CH1 200mA Ω
BW
M20µs A CH1 100mA
T 10.2%
1
2
CH2 20mV
BW
T
Figure 44. Output Transient Response, VOUT = 5 V, COUT = 2.2 μF, CH1 Load
Current, CH2 VOUT
Input Bypass Capacitor
Connecting a 2.2 µF capacitor from VIN to GND reduces the
circuit sensitivity to the PCB layout, especially when long input
traces or high source impedance is encountered. If greater than
2.2 µF of output capacitance is required, increase the input
capacitor to match it.
Input and Output Capacitor Properties
Any good quality ceramic capacitors can be used with the
ADP7142, as long as they meet the minimum capacitance and
maximum ESR requirements. Ceramic capacitors are manufac-
tured with a variety of dielectrics, each with different behavior
over temperature and applied voltage. Capacitors must have a
dielectric adequate to ensure the minimum capacitance over
the necessary temperature range and dc bias conditions. X5R or
X7R dielectrics with a voltage rating of 6.3 V to 100 V are
recommended. Y5V and Z5U dielectrics are not recommended,
due to their poor temperature and dc bias characteristics.
Figure 45 depicts the capacitance vs. voltage bias characteristic of
an 0805, 2.2 µF, 10 V, X5R capacitor. The voltage stability of a
capacitor is strongly influenced by the capacitor size and voltage
rating. In general, a capacitor in a larger package or higher voltage
rating exhibits better stability. The temperature variation of the
X5R dielectric is ~±15% over the −40°C to +85°C temperature
range and is not a function of package or voltage rating.
CAPACITANCE (µF)
DC BIAS VOLTAGE (V)
121086420
0
0.5
1.0
1.5
2.0
2.5
11848-043
Figure 45. Capacitance vs. Voltage Characteristic
Use Equation 1 to determine the worst-case capacitance
accounting for capacitor variation over temperature, component
tolerance, and voltage.
CEFF = CBIAS × (1 − TEMPCO) × (1 − TOL) (4)
where:
CBIAS is the effective capacitance at the operating voltage.
TEMPCO is the worst-case capacitor temperature coefficient.
TOL is the worst-case component tolerance.
In this example, the worst-case temperature coefficient
(TEMPCO) over −40°C to +85°C is assumed to be 15% for an
X5R dielectric. The tolerance of the capacitor (TOL) is assumed
to be 10%, and CBIAS is 2.09 F at 5 V, as shown in Figure 45.
These values in Equation 1 yield
CEFF = 2.09 F × (1 − 0.15) × (1 − 0.1) = 1.59 F (5)
Therefore, the capacitor chosen in this example meets the
minimum capacitance requirement of the LDO over temper-
ature and tolerance at the chosen output voltage.
To guarantee the performance of the ADP7142, it is imperative
that the effects of dc bias, temperature, and tolerances on the
behavior of the capacitors be evaluated for each application.
Data Sheet ADP7142
Rev. H | Page 15 of 23
PROGRAMABLE PRECISION ENABLE
The ADP7142 uses the EN pin to enable and disable the
VOUT pin under normal operating conditions. As shown in
Figure 46, when a rising voltage on EN crosses the upper threshold,
nominally 1.2 V, VOUT turns on. When a falling voltage on EN
crosses the lower threshold, nominally 1.1 V, VOUT turns off.
The hysteresis of the EN threshold is approximately 100 mV.
V
OUT
(V)
V
EN
(V)
1.301.251.201.151.101.05
0
0.5
1.0
1.5
2.0
2.5
3.5
3.0
–40°C
+25°C
+125°C
11848-044
Figure 46. Typical VOUT Response to EN Pin Operation
The upper and lower thresholds are user programmable and
can be set higher than the nominal 1.2 V threshold by using
two resistors. The resistance values, REN1 and REN2, can be
determined from
REN2 = nominally 10 k to 100 k (6)
REN1 = REN2 × (VIN − 1.2 V)/1.2 V (7)
where:
VIN is the desired turn-on voltage.
The hysteresis voltage increases by the factor (REN1 + REN2)/ REN2.
For the example shown in Figure 47, the enable threshold is 3.6 V
with a hysteresis of 300 mV.
VOUT
SENSE/ADJ
VIN
ADP7142
GND
C
IN
2.2µF
C
OUT
2.2µF
EN
OFF
ON
V
IN
= 8V V
OUT
= 6V
R1
10kΩ
R2
20kΩ
R
EN1
200kΩ
R
EN2
100kΩ
11848-045
Figure 47. Typical EN Pin Voltage Divider
Figure 46 shows the typical hysteresis of the EN pin. This prevents
on/off oscillations that can occur due to noise on the EN pin as
it passes through the threshold points.
SOFT START
The ADP7142 uses an internal soft start (when the SS pin is left
open) to limit the inrush current when the output is enabled. The
start-up time for the 3.3 V option is approximately 380 s from
the time the EN active threshold is crossed to when the output
reaches 90% of its final value. As shown in Figure 48, the start-up
time is dependent on the output voltage setting.
V
OUT
(V)
TIME (ms)
1.00.90.80.70.60.50.40.30.20.10
0
1
2
3
4
6
5
V
EN
V
IN
= 1.8V
V
IN
= 3.3V
V
IN
= 5.0V
11848-046
Figure 48. Typical Start-Up Behavior
An external capacitor connected to the SS pin determines the
soft start time. The SS pin can be left open for a typical 380 s
start-up time. Do not ground this pin. When an external soft
start capacitor (CSS) is used, the soft start time is determined by
the following equation:
SSTIME (sec) = tSTARTUP (0 pF) + (0.6 × CSS)/ISS (8)
where:
tSTARTUP (at 0 pF) is the start-up time at CSS = 0 pF (typically 380 µs).
CSS is the soft start capacitor (F).
ISS is the soft start current (typically 1.15 µA).
V
OUT
(V)
TIME (ms)
109876543210
0
0.5
1.0
2.0
3.0
3.5
1.5
2.5
V
EN
NO SS CAP
1nF
2nF
4.7nF
6.8nF
10nF
11848-047
Figure 49. Typical Soft Start Behavior, Different CSS
ADP7142 Data Sheet
Rev. H | Page 16 of 23
NOISE REDUCTION OF THE ADP7142 IN
ADJUSTABLE MODE
The ultralow output noise of the ADP7142 is achieved by
keeping the LDO error amplifier in unity gain and setting the
reference voltage equal to the output voltage. This architecture
does not work for an adjustable output voltage LDO in the
conventional sense. However, the ADP7142 architecture allows
any fixed output voltage to be set to a higher voltage with an
external voltage divider. For example, a fixed 5 V output can be
set to a 10 V output according to Equation 3 (see Figure 50):
VOUT = 5 V (1 + R1/R2)
The disadvantage in using the ADP7142 in this manner is that
the output voltage noise is proportional to the output voltage.
Therefore, it is best to choose a fixed output voltage that is close
to the target voltage to minimize the increase in output noise.
The adjustable LDO circuit can be modified to reduce the
output voltage noise to levels close to that of the fixed output
ADP7142. The circuit shown in Figure 50 adds two additional
components to the output voltage setting resistor divider. CNR
and RNR are added in parallel with R1 to reduce the ac gain of
the error amplifier. RNR is chosen to be small with respect to R2.
If RNR is 1% to 10% of the value of R2, the minimum ac gain of
the error amplifier is approximately 0.1 dB to 0.8 dB. The actual
gain is determined by the parallel combination of RNR and R1.
This gain ensures that the error amplifier always operates at
slightly greater than unity gain.
CNR is chosen by setting the reactance of CNR equal to R1 − RNR
at a frequency between 1 Hz and 50 Hz. This setting places the
frequency where the ac gain of the error amplifier is 3 dB down
from its dc gain.
V
OUT
= 12V
V
IN
= 14V VOUTVIN
GND
SENSE/ADJ
EN
100kΩ
200kΩ
C
OUT
2.2µF
C
IN
2.2µF
ON
OFF
R
NR
1kΩ
R2
10kΩ
R1
91kΩ C
NR
1µF
11848-048
Figure 50. Noise Reduction Modification
The noise of the adjustable LDO is found by using the
following formula, assuming the noise of a fixed output LDO is
approximately 11 V.
Noise = 11 V × (RPAR + R2)/R2 (9)
where RPAR is a parallel combination of R1 and RNR.
Based on the component values shown in Figure 50, the ADP7142
has the following characteristics:
DC gain of 10 (20 dB)
3 dB roll-off frequency of 1.75 Hz
High frequency ac gain of 1.099 (0.82 dB)
Theoretical noise reduction factor of 9.1 (19.2 dB)
Measured rms noise of the adjustable LDO without noise
reduction is 70 µV rms
Measured rms noise of the adjustable LDO with noise
reduction is 12 µV rms
Measured noise reduction of approximately 15.3 dB
Note that the measured noise reduction is less than the
theoretical noise reduction. Figure 51 shows the noise spectral
density of an adjustable ADP7142 set to 6 V and 12 V with and
without the noise reduction network. The output noise with the
noise reduction network is approximately the same for both
voltages, especially beyond 100 Hz. The noise of the 6 V and 12 V
outputs without the noise reduction network differs by a factor
of 2 up to approximately 20 kHz. Above 40 kHz, the closed
loop gain of the error amplifier is limited by its open loop gain
characteristic. Therefore, the noise contribution from 20 kHz to
100 kHz is less than what it would be if the error amplifier had
infinite bandwidth. This is also the reason why the noise is less
than what might be expected simply based on the dc gain, that
is, 70 µV rms vs. 110 µV rms.
NOISE SPECTRAL DENSITY (nV/
√
Hz)
FREQUENCY (Hz)
10M1M100k10k1k100101
1
10
100
10k
100k
1k
11848-100
12V NOISE REDUCTION
12V NO NOISE REDUCTION
6V NOISE REDUCTION
6V NO NOISE REDUCTION
Figure 51. 6 V and 12 V Output Voltage with and Without Noise Reduction
Network
EFFECT OF NOISE REDUCTION ON START-UP TIME
The start-up time of the ADP7142 is affected by the noise
reduction network and must be considered in applications
where power supply sequencing is critical.
The noise reduction circuit adds a pole in the feedback loop,
slowing down the start-up time. The start-up time for an adjustable
model with a noise reduction network can be approximated
using the following equation:
SSNRTIME (sec) = 5.5 × CNR × (RNR + R1)
For a CNR, RNR, and R1 combination of 1 µF, 1 k, and 91 k as
shown in Figure 50, the start-up time is approximately 0.5 sec.
When SSNRTIME is greater than SSTIME, SSNRTIME dictates the
length of the start-up time instead of the soft start capacitor.
Data Sheet ADP7142
Rev. H | Page 17 of 23
CURRENT-LIMIT AND THERMAL OVERLOAD
PROTECTION
The ADP7142 is protected against damage due to excessive
power dissipation by current and thermal overload protection
circuits. The ADP7142 is designed to current limit when the
output load reaches 360 mA (typical). When the output load
exceeds 360 mA, the output voltage is reduced to maintain a
constant current limit.
Thermal overload protection is included, which limits the
junction temperature to a maximum of 150°C (typical). Under
extreme conditions (that is, high ambient temperature and/or
high power dissipation) when the junction temperature starts
to rise above 150°C, the output is turned off, reducing the
output current to zero. When the junction temperature drops
below 135°C, the output is turned on again, and output current
is restored to its operating value.
Consider the case where a hard short from VOUT to ground
occurs. At first, the ADP7142 current limits, so that only 360 mA
is conducted into the short. If self heating of the junction is great
enough to cause its temperature to rise above 150°C, thermal
shutdown activates, turning off the output and reducing the
output current to zero. As the junction temperature cools and
drops below 135°C, the output turns on and conducts 360 mA
into the short, again causing the junction temperature to rise
above 150°C. This thermal oscillation between 135°C and 150°C
causes a current oscillation between 360 mA and 0 mA that
continues as long as the short remains at the output.
Current and thermal limit protections protect the device
against accidental overload conditions. For reliable operation,
device power dissipation must be externally limited so that the
junction temperature does not exceed 125°C.
THERMAL CONSIDERATIONS
In applications with a low input-to-output voltage differential,
the ADP7142 does not dissipate much heat. However, in appli-
cations with high ambient temperature and/or high input voltage,
the heat dissipated in the package may become large enough to
cause the junction temperature of the die to exceed the
maximum junction temperature of 125°C.
When the junction temperature exceeds 150°C, the converter
enters thermal shutdown. It recovers only after the junction
temperature has decreased below 135°C to prevent any permanent
damage. Therefore, thermal analysis for the chosen application
is very important to guarantee reliable performance over all
conditions. The junction temperature of the die is the sum of
the ambient temperature of the environment and the temperature
rise of the package due to the power dissipation, as shown in
Equation 2.
To guarantee reliable operation, the junction temperature of
the ADP7142 must not exceed 125°C. To ensure that the
junction temperature stays below this maximum value, the user
must be aware of the parameters that contribute to junction
temperature changes. These parameters include ambient
temperature, power dissipation in the power device, and
thermal resistances between the junction and ambient air (θJA).
The θJA number is dependent on the package assembly
compounds that are used and the amount of copper used to
solder the package GND pins to the PCB.
Table 6 shows typical θJA values of the 8-lead SOIC, 6-lead LFCSP,
and 5-Lead TSOT packages for various PCB copper sizes. Table 7
shows the typical ΨJB values of the 8-lead SOIC, 6-lead LFCSP,
and 5-lead TSOT.
Table 6. Typical θJA Values
Copper Size (mm2)
θJA (°C/W)
LFCSP SOIC TSOT
251 182.8 N/A2 N/A2
50 N/A2 181.4 152
100 142.6 145.4 146
500 83.9 89.3 131
1000 71.7 77.5 N/A2
6400 57.4 63.2 N/A2
1 Device soldered to minimum size pin traces.
2 N/A means not applicable.
Table 7. Typical ΨJB Values
Model ΨJB (°C/W)
6-Lead LFCSP 24
8-Lead SOIC 38.8
5-Lead TSOT 43
To calculate the junction temperature of the ADP7142, use
Equation 1:
TJ = TA + (PD × θJA)
where:
TA is the ambient temperature.
PD is the power dissipation in the die, given by
PD = [(VIN − VOUT) × ILOAD] + (VIN × IGND) (10)
where:
VIN and VOUT are input and output voltages, respectively.
ILOAD is the load current.
IGND is the ground current.
Power dissipation due to ground current is quite small and can
be ignored. Therefore, the junction temperature equation
simplifies to the following:
TJ = TA + {[(VIN − VOUT) × ILOAD] × θJA} (11)
As shown in Equation 4, for a given ambient temperature, input-
to-output voltage differential, and continuous load current, there
exists a minimum copper size requirement for the PCB to ensure
that the junction temperature does not rise above 125°C. Figure 52
to Figure 60 show junction temperature calculations for different
ambient temperatures, power dissipation, and areas of PCB
copper.
ERA RA \\
ADP7142 Data Sheet
Rev. H | Page 18 of 23
25
35
45
55
65
75
85
95
105
115
125
135
145
0
JUNCTION TEMPE
R
A
TURE (°C)
TOTAL POWER DISSIPATION (W)
0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4
6400mm
2
500mm
2
25mm
2
T
J
MAX
11848-049
Figure 52. LFCSP, TA = 25°C
50
60
70
80
90
100
110
120
130
140
0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8
JUNCTION TEMPERATURE (°C)
TOTAL POWER DISSIPATION (W)
6400mm
2
500mm
2
25mm
2
T
J
MAX
11848-050
Figure 53. LFCSP, TA = 50°C
50
60
70
80
90
100
110
120
130
140
0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8
JUNCTION TEMPERATURE (°C)
TOTAL POWER DISSIPATION (W)
6400mm
2
500mm
2
25mm
2
T
J
MAX
11848-051
Figure 54. LFCSP, TA = 85°C
JUNCTION TEMPE
R
A
TURE (°C)
TOTAL POWER DISSIPATION (W)
0
20
40
60
80
100
120
140
0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5
T
B
= 25°C
T
B
= 50°C
T
B
= 65°C
T
B
= 85°C
T
J
MAX
11848-052
Figure 55. SOIC, TA = 25°C
50
60
70
80
90
100
110
120
130
140
0 0.2 0.4 0.6 0.8 1.0 1.2
JUNCTION TEMPERATURE (°C)
TOTAL POWER DISSIPATION (W)
6400mm
2
500mm
2
50mm
2
T
J
MAX
11848-155
Figure 56. SOIC, TA = 50°C
65
145
135
125
115
105
95
85
75
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8
JUNCTION TEMPERATURE (°C)
TOTAL POWER DISSIPATION (W)
6400mm
2
500mm
2
50mm
2
T
J
MAX
11848-156
Figure 57. SOIC, TA = 85°C
RA RA
Data Sheet ADP7142
Rev. H | Page 19 of 23
25
35
45
55
65
75
85
95
105
115
125
135
145
0 0.1 0.2 0.3 0.4 0.5 0.6 0.8 1.00.7 0.9
JUNCTION TEMPERATURE (°C)
TOTAL POWER DISSIPATION (W)
500mm
2
100mm
2
50mm
2
T
J
MAX
11848-157
Figure 58. TSOT, TA = 25°C
50
140
130
120
110
100
90
80
70
60
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7
JUNCTION TEMPERATURE (°C)
TOTAL POWER DISSIPATION (W)
500mm
2
100mm
2
50mm
2
T
J
MAX
11848-158
Figure 59. TSOT, TA = 50°C
65
145
75
85
95
105
115
125
135
00.400.350.300.250.200.150.100.05
JUNCTION TEMPERATURE (°C)
TOTAL POWER DISSIPATION (W)
500mm
2
100mm
2
50mm
2
T
J
MAX
11848-159
Figure 60. TSOT, TA = 85°C
In the case where the board temperature is known, use the
thermal characterization parameter, ΨJB, to estimate the
junction temperature rise (see Figure 61, Figure 62, and
Figure 63). Calculate the maximum junction temperature by
using Equation 2.
TJ = TB + (PD × ΨJB)
The typical value of ΨJB is 24°C/W for the 8-lead LFCSP package,
38.8°C/W for the 8-lead SOIC package, and 43°C/W for the 5-lead
TSOT package.
JUNCTION TEMPE
R
A
TURE (°C)
TOTAL POWER DISSIPATION (W)
0
20
40
60
80
100
120
140
0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5
T
B
= 25°C
T
B
= 50°C
T
B
= 65°C
T
B
= 85°C
T
J
MAX
11848-160
Figure 61. LFCSP Junction Temperature Rise, Different Board Temperatures
JUNCTION TEMPE
R
A
TURE (°C)
TOTAL POWER DISSIPATION (W)
0
20
40
60
80
100
120
140
0 0.5 1.0 1.5 2.0 2.5 3.0
T
B
= 25°C
T
B
= 50°C
T
B
= 65°C
T
B
= 85°C
T
J
MAX
11848-161
Figure 62. SOIC Junction Temperature Rise, Different Board Temperatures
JUNCTION TEMPE
R
A
TURE (°C)
TOTAL POWER DISSIPATION (W)
0
20
40
60
80
100
120
140
0 0.5 1.0 1.5 2.0 2.5
T
B
= 25°C
T
B
= 50°C
T
B
= 65°C
T
B
= 85°C
T
J
MAX
11848-162
Figure 63. TSOT Junction Temperature Rise, Different Board Temperatures
«A» ’L/kd ("7“ \IL/ \:\1 »y\!\r\ L (\vwr\r\ \)\45/§J rxr f\i\ k/xzxzxx 5%
ADP7142 Data Sheet
Rev. H | Page 20 of 23
PRINTED CIRCUIT BOARD LAYOUT CONSIDERATIONS
Heat dissipation from the package can be improved by increasing
the amount of copper attached to the pins of the ADP7142.
However, as listed in Table 6, a point of diminishing returns is
eventually reached, beyond which an increase in the copper size
does not yield significant heat dissipation benefits.
Place the input capacitor as close as possible to the VIN pin and
GND pin. Place the output capacitor as close as possible to the
VOUT and GND pins. Use of 0805 or 1206 size capacitors and
resistors achieves the smallest possible footprint solution on
boards where area is limited.
11848-054
Figure 64. Example LFCSP PCB Layout
11848-164
Figure 65. Example SOIC PCB Layout
6ND ANALOG 6ND DEVICES ADP7142/71187EVALZ J1 :1 ll U1 [F c2 - " I vow ca .0 JPlfl flwzvow SENSE/ADJ O. .0 N to
Data Sheet ADP7142
Rev. H | Page 21 of 23
11848-165
Figure 66. Example TSOT PCB Layout
Table 8. Recommended LDOs for Very Low Noise Operation
Device
Number
VIN
Range (V)
VOUT
Fixed (V)
VOUT
Adjust
(V)
IOUT
(mA)
IQ at
IOUT
(µA)
IGND-SD
Max
(µA)
Soft
Start PGOOD
Noise
(Fixed)
10 Hz to
100 kHz
(µV rms)
PSRR
100 kHz
(dB)
PSRR
1 MHz Package
ADP7102 3.3 to 20 1.5 to 9 1.22 to
19
300 750 75 No Yes 15 60 40 dB 3 mm × 3 mm
8-lead LFCSP,
8-lead SOIC
ADP7104 3.3 to 20 1.5 to 9 1.22 to
19
500 900 75 No Yes 15 60 40 dB 3 mm × 3 mm
8-lead LFCSP,
8-lead SOIC
ADP7105 3.3 to 20 1.8, 3.3, 5 1.22 to
19
500 900 75 Yes Yes 15 60 40 dB 3 mm × 3 mm
8-lead LFCSP,
8-lead SOIC
ADP7112 2.7 to 20 1.2 to 5 1.2 to 19 200 180 10 Yes No 11 68 50 dB 1 mm ×
1.2 mm
6-ball WLCSP
ADP7118 2.7 to 20 1.2 to 5 1.2 to 19 200 180 10 Yes No 11 68 50 dB 2 mm × 2 mm
6-lead LFCSP,
8-lead SOIC,
5-lead TSOT
ADP7142 2.7 to 40 1.2 to 5 1.2 to 39 200 180 10 Yes No 11 68 50 dB 2 mm × 2 mm
6-lead LFCSP,
8-lead SOIC,
5-lead TSOT
ADP7182 −2.7 to
−28
−1.8 to
−5
−1.22 to
−27
−200 −650 −8 No No 18 45 45 dB 2 mm × 2 mm
6-lead LFCSP,
3 mm × 3 mm
8-lead LFCSP,
5-lead TSOT
Table 9. Related Devices
Model Input Voltage (V) Output Current (mA) Package
ADP7118CP 2.7 to 20 200 6-lead LFCSP
ADP7118RD 2.7 to 20 200 8-lead SOIC
ADP7118UJ 2.7 to 20 200 5-lead TSOT
ADP7112CB 2.7 to 20 200 6-ball WLCSP
ADP7142 Data Sheet
Rev. H | Page 22 of 23
OUTLINE DIMENSIONS
1.70
1.60
1.50
0.425
0.350
0.275
TOP VIEW
6
1
4
3
0.35
0.30
0.25
BOTTOM VIEW
PIN 1 INDEX
AREA
0.60
0.55
0.50
1.10
1.00
0.90
0.20 REF
0.05 MAX
0.02 NOM
0.65 BSC
EXPOSED
PAD
FOR PROPER CONNECTION OF
THE EXPOSED PAD, REFER TO
THE PIN CONFIGURATION AND
FUNCTION DESCRIPTIONS
SECTION OF THIS DATA SHEET.
2.10
2.00 SQ
1.90
0.15 MIN
08-17-2018-D
SEATING
PLANE
PIN 1
INDICATORAREAOPTIONS
(SEEDETAILA)
DETAIL A
(JEDEC 95)
PKG-003581
Figure 67. 6-Lead Lead Frame Chip Scale Package [LFCSP]
2.00 mm × 2.00 mm Body and 0.55 mm Package Height
(CP-6-3)
Dimensions shown in millimeters
COMPLIANT TO JEDEC STANDARDS MS-012-AA
06-02-2011-B
1.27
0.40
1.75
1.35
2.29
2.29
0.356
0.457
4.00
3.90
3.80
6.20
6.00
5.80
5.00
4.90
4.80
0.10 MAX
0.05 NOM
3.81 REF
0.25
0.17
8°
0°
0.50
0.25
45°
COPLANARITY
0.10
1.04 REF
8
14
5
1.27 BSC
S
EATING
PLANE
FOR PROPER CONNECTION OF
THE EXPOSED PAD, REFER TO
THE PIN CONFIGURATION AND
FUNCTION DESCRIPTIONS
SECTION OF THIS DATA SHEET.
BOTTOM VIEW
TOP VIEW
0.51
0.31
1.65
1.25
Figure 68. 8-Lead Standard Small Outline Package, with Exposed Pad [SOIC_N_EP]
Narrow Body
(RD-8-1)
Dimensions shown in millimeters
ANALOG DEVICES www.ana|og.oum
Data Sheet ADP7142
Rev. H | Page 23 of 23
COMPLIANT TO JEDEC STANDARDS MO-193-AB
0.95 BSC
1.90 REF
0.90
0.70
0.20
0.08
0.60
0.45
0.30
8°
4°
0°
0.50
0.30
0.10 MAX
1.00 MAX
54
123
END VIEW
TOP VIEW
SIDE VIEW
04-05-2017-B
PKG-000882
3.05
2.90
2.75
3.05
2.80
2.55
1.75
1.60
1.45
SEATING
PLANE
Figure 69. 5-Lead Thin Small Outline Transistor Package [TSOT]
(UJ-5)
Dimensions shown in millimeters
ORDERING GUIDE
Model1
Temperature
Range Output Voltage (V)2, 3 Package Description Package Option
Marking
Code
ADP7142ACPZN-R7 −40°C to +125°C Adjustable (1.2 V) 6-Lead LFCSP CP-6-3 LP4
ADP7142ACPZN1.8-R7 −40°C to +125°C 1.8 6-Lead LFCSP CP-6-3 LP5
ADP7142ACPZN2.5-R7 −40°C to +125°C 2.5 6-Lead LFCSP CP-6-3 LP7
ADP7142ACPZN3.3-R7 −40°C to +125°C 3.3 6-Lead LFCSP CP-6-3 LP6
ADP7142ACPZN3.8-R7 −40°C to +125°C 3.8 6-Lead LFCSP CP-6-3 LVK
ADP7142ACPZN5.0-R7 −40°C to +125°C 5 6-Lead LFCSP CP-6-3 LP8
ADP7142ARDZ −40°C to +125°C Adjustable (1.2 V) 8-Lead SOIC_N_EP RD-8-1
ADP7142ARDZ-R7 −40°C to +125°C Adjustable (1.2 V) 8-Lead SOIC_N_EP RD-8-1
ADP7142ARDZ-1.8 −40°C to +125°C 1.8 8-Lead SOIC_N_EP RD-8-1
ADP7142ARDZ-1.8-R7 −40°C to +125°C 1.8 8-Lead SOIC_N_EP RD-8-1
ADP7142ARDZ-2.5 −40°C to +125°C 2.5 8-Lead SOIC_N_EP RD-8-1
ADP7142ARDZ-2.5-R7 −40°C to +125°C 2.5 8-Lead SOIC_N_EP RD-8-1
ADP7142ARDZ-3.3 −40°C to +125°C 3.3 8-Lead SOIC_N_EP RD-8-1
ADP7142ARDZ-3.3-R7 −40°C to +125°C 3.3 8-Lead SOIC_N_EP RD-8-1
ADP7142ARDZ-5.0 −40°C to +125°C 5 8-Lead SOIC_N_EP RD-8-1
ADP7142ARDZ-5.0-R7 −40°C to +125°C 5 8-Lead SOIC_N_EP RD-8-1
ADP7142AUJZ-R2 −40°C to +125°C Adjustable (1.2 V) 5-Lead TSOT UJ-5 LP4
ADP7142AUJZ-R7 −40°C to +125°C Adjustable (1.2 V) 5-Lead TSOT UJ-5 LP4
ADP7142AUJZ-1.8-R7 −40°C to +125°C 1.8 5-Lead TSOT UJ-5 LP5
ADP7142AUJZ-2.5-R7 −40°C to +125°C 2.5 5-Lead TSOT UJ-5 LP7
ADP7142AUJZ-3.3-R7 −40°C to +125°C 3.3 5-Lead TSOT UJ-5 LP6
ADP7142AUJZ-5.0-R7 −40°C to +125°C 5 5-Lead TSOT UJ-5 LP8
ADP7142UJ-EVALZ TSOT Evaluation Board
ADP7142CP-EVALZ LFCSP Evaluation Board
ADP7142RD-EVALZ SOIC Evaluation Board
1 Z = RoHS Compliant Part.
2 For additional voltage options, contact a local Analog Devices, Inc., sales or distribution representative.
3 The evaluation boards are preconfigured with an adjustable ADP7142.
©2014–2020 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D11848-3/20(H)