ADP7142AUJZ-5.0-R7
更新时间:2024-09-18 18:01:47
品牌:ADI
描述:40 V, 200 mA, Low Noise, CMOS LDO Linear Regulator
ADP7142AUJZ-5.0-R7 概述
40 V, 200 mA, Low Noise, CMOS LDO Linear Regulator
ADP7142AUJZ-5.0-R7 数据手册
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PDF下载40 V, 200 mA, Low Noise,
CMOS LDO Linear Regulator
ADP7142
Data Sheet
FEATURES
TYPICAL APPLICATION CIRCUITS
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,
ADP7142
V
= 6V
V
= 5V
IN
OUT
VIN
VOUT
C
C
OUT
2.2µF
VOUT ≤ 5 V, VIN = 7 V
IN
2.2µF
Input voltage range: 2.7 V to 40 V
Maximum output current: 200 mA
Initial accuracy: 0.8%
Accuracy over line, load, and temperature
1.1%, TJ = −40°C to +85°C
SENSE/ADJ
ON
EN
SS
C
1nF
GND
SS
OFF
Figure 1. ADP7142 with Fixed Output Voltage, 5 V
1.8%, TJ = −40°C to +125°C
Low dropout voltage: 200 mV (typical) at a 200 mA load,
ADP7142
V
= 7V
V
= 6V
OUT
IN
VOUT = 5 V
VIN
VOUT
C
C
OUT
2.2µF
User programmable soft start (LFCSP and SOIC only)
Low quiescent current, IGND = 50 μA (typical) with no load
Low shutdown current: 1.8 μA at VIN = 5 V, 3.0 μA 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, and 5.0 V
16 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
IN
2kΩ
2.2µF
SENSE/ADJ
10kΩ
ON
EN
SS
C
GND
SS
OFF
1nF
Figure 2. ADP7142 with 5 V Output Adjusted to 6 V
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
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 40 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 μV rms independent of
the output voltage for the fixed options of 5 V or less.
3.8 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.
The ADP7142 is available in 16 fixed output voltage options.
The following voltages are available from stock: 1.2 V (adjustable),
1.8 V, 2.5 V, 3.3 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,
Rev. D
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Tel: 781.329.4700 ©2014–2017 Analog Devices, Inc. All rights reserved.
Technical Support
www.analog.com
ADP7142* PRODUCT PAGE QUICK LINKS
Last Content Update: 11/18/2017
COMPARABLE PARTS
View a parametric search of comparable parts.
REFERENCE MATERIALS
Solutions Bulletins & Brochures
• Ultralow Noise, High Rejection Low Dropout Regulators
EVALUATION KITS
• ADP7118/ADP7142 Evaluation Board
DESIGN RESOURCES
• ADP7142 Material Declaration
• PCN-PDN Information
DOCUMENTATION
Application Notes
• Quality And Reliability
• Symbols and Footprints
• AN-1359: Low Noise, Dual-Supply Solution Using the
ADP5070 for the Precision AD5761R Bipolar DAC in
Single-Supply Systems
DISCUSSIONS
View all ADP7142 EngineerZone Discussions.
Data Sheet
• ADP7142: 40 V, 200 mA, Low Noise, CMOS LDO Linear
Regulator Data Sheet
SAMPLE AND BUY
Visit the product page to see pricing options.
User Guides
• UG-616: Evaluating the ADP7118/ADP7142 20 V/40 V, 200
mA, Low Noise, CMOS LDOS
TECHNICAL SUPPORT
Submit a technical question or find your regional support
number.
TOOLS AND SIMULATIONS
• ADI Linear Regulator Design Tool and Parametric Search
• ADIsimPower™ Voltage Regulator Design Tool
DOCUMENT FEEDBACK
Submit feedback for this data sheet.
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ADP7142
Data Sheet
TABLE OF CONTENTS
Features .............................................................................................. 1
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
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
REVISION HISTORY
11/2017—Rev. C to Rev. D
4/2015—Rev. A to Rev. B
Changes to Ordering Guide .......................................................... 22
Updated Outline Dimensions ....................................................... 23
Changes to Ordering Guide.......................................................... 23
12/2014—Rev. 0 to Rev. A
6/2016—Rev. B to Rev. C
Changes to Figure 36 to Figure 41................................................ 12
Changes to Figure 44...................................................................... 14
Updated Figure 67; Outline Dimensions .................................... 22
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
9/2014—Revision 0: Initial Version
Rev. D | Page 2 of 23
Data Sheet
ADP7142
SPECIFICATIONS
VIN = VOUT +1 V or 2.7 V, whichever is greater, VOUT = 5 V, E N = 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
VIN
Test Conditions/Comments
Min
Typ
Max
40
Unit
V
INPUT VOLTAGE RANGE
OPERATING SUPPLY CURRENT
2.7
IGND
IOUT = 0 µA
50
80
180
1.8
3.0
140
190
320
µA
µA
µA
µA
µA
µA
IOUT = 10 mA
IOUT = 200 mA
EN = GND
EN = GND, VIN = 40 V
EN = GND
SHUTDOWN CURRENT
IGND-SD
10
OUTPUT VOLTAGE ACCURACY
Output Voltage Accuracy
VOUT
IOUT = 10 mA, TJ = 25°C
100 μA < IOUT < 200 mA, VIN = (VOUT + 1 V) to 40 V,
TJ = −40°C to +85°C
–0.8
–1.2
+0.8
+1.5
%
%
100 μA < IOUT < 200 mA, VIN = (VOUT + 1 V) to 40 V
–1.8
+1.8
%
LINE REGULATION
∆VOUT/∆VIN VIN = (VOUT + 1 V) to 40 V
∆VOUT/∆IOUT IOUT = 100 μA to 200 mA
–0.01
+0.01 %/V
0.002 0.004 %/mA
LOAD REGULATION1
SENSE INPUT BIAS CURRENT
DROPOUT VOLTAGE2
SENSEI-BIAS
VDROPOUT
100 μA < IOUT < 200 mA VIN = (VOUT + 1 V) to 40 V
10
1000
60
420
nA
mV
mV
µs
IOUT = 10 mA
IOUT = 200 mA
VOUT = 5 V
30
200
380
1.15
360
START-UP TIME3
tSTART-UP
SSI-SOURCE
ILIMIT
SOFT START SOURCE CURRENT
CURRENT-LIMIT THRESHOLD4
THERMAL SHUTDOWN
Thermal Shutdown Threshold
Thermal Shutdown Hysteresis
UNDERVOLTAGE THRESHOLDS
Input Voltage Rising
Input Voltage Falling
Hysteresis
SS = GND
µA
mA
250
2.2
460
TSSD
TJ rising
150
15
°C
°C
TSSD-HYS
UVLORISE
UVLOFALL
UVLOHYS
2.69
V
V
230
mV
PRECISION EN INPUT
Logic High
Logic Low
Logic Hysteresis
Leakage Current
2.7 V ≤ VIN ≤ 40 V
ENHIGH
ENLOW
ENHYS
IEN-LKG
tEN-DLY
1.15
1.06
1.22
1.12
100
0.04
80
1.30
1.18
V
V
mV
µA
μs
EN = VIN or GND
1
Delay Time
From EN rising from 0 V to VIN to 0.1 × VOUT
10 Hz to 100 kHz, all output voltage options
1 MHz, VIN = 7 V, VOUT = 5 V
100 kHz, VIN = 7 V, VOUT = 5 V
10 kHz, VIN = 7 V, VOUT = 5 V
OUTPUT NOISE
OUTNOISE
PSRR
11
µV rms
dB
dB
dB
POWER SUPPLY REJECTION RATIO
50
68
88
1 Based on an endpoint calculation using 100 μA 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.
Rev. D | Page 3 of 23
ADP7142
Data Sheet
INPUT AND OUTPUT CAPACITANCE, RECOMMENDED SPECIFICATIONS
Table 2.
Parameter
Symbol
Test Conditions/Comments
Min
Typ
Max
Unit
INPUT AND OUTPUT CAPACITANCE
Minimum Capacitance1
Capacitor Effective Series Resistance (ESR)
CMIN
RESR
TA = −40°C to +125°C
TA = −40°C to +125°C
1.5
0.001
µF
Ω
0.3
1 The minimum input and output capacitance must be greater than 1.5 μF 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.
Rev. D | Page 4 of 23
Data Sheet
ADP7142
ABSOLUTE MAXIMUM RATINGS
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
Table 3.
Parameter
Rating
VIN to GND
VOUT to GND
EN to GND
SENSE/ADJ to GND
SS to GND
–0.3 V to +44 V
–0.3 V to VIN
–0.3 V to +44 V
–0.3 V to +6 V
–0.3 V to VIN or +6 V
(whichever is less)
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.
Storage Temperature Range
Junction Temperature (TJ)
–65°C to +150°C
150°C
Ψ
JB 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
Operating Ambient Temperature
(TA) Range
Soldering Conditions
–40°C to +125°C
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
TJ = TB + (PD × ΨJB)
(2)
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.
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
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
Package Type
6-Lead LFCSP
8-Lead SOIC
5-Lead TSOT
θJA
θJC
ΨJB
47.1
32.7
43
Unit
°C/W
°C/W
°C/W
72.1
52.7
170
42.3
41.5
N/A1
1 N/A means not applicable.
temperature, the power dissipation (PD) of the device, and the
junction-to-ambient thermal resistance of the package (θJA).
ESD CAUTION
Maximum TJ is calculated from the TA and PD using the formula
TJ = TA + (PD × θJA)
(1)
Rev. D | Page 5 of 23
ADP7142
Data Sheet
PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS
VOUT
SENSE/ADJ
GND
1
2
3
6
5
4
VIN
VOUT
VOUT
1
2
3
4
8
7
6
5
VIN
VIN
SS
ADP7142
SS
ADP7142
TOP VIEW
(Not to Scale)
TOP VIEW
(Not to Scale)
SENSE/ADJ
GND
EXPOSED PAD
EN
EN
NOTES
NOTES
1. THE EXPOSED PAD ON THE BOTTOM OF THE PACKAGE
ENHANCES THERMAL PERFORMANCE AND IS
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.
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
Figure 3. 6-Lead LFCSP Pin Configuration
1
2
3
5
4
VIN
GND
EN
VOUT
ADP7142
TOP VIEW
(Not to Scale)
SENSE/ADJ
Figure 4. 5-Lead TSOT Pin Configuration
Table 5. Pin Function Descriptions
Pin No.
6-Lead
LFCSP
8-Lead
SOIC
5-Lead
TSOT
Mnemonic Description
VOUT Regulated Output Voltage. Bypass VOUT to GND with a 2.2 µF or greater capacitor.
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).
1
2
1, 2
3
5
4
3
4
4
5
2
3
GND
EN
Ground.
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
6
Not
applicable
1
SS
Soft Start. An external capacitor connected to this pin determines the soft-start
time. Leave this pin open for a typical 380 μs start-up time. Do not ground this pin.
Regulator Input Supply. Bypass VIN to GND with a 2.2 µF or greater capacitor.
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.
7, 8
VIN
EP
Rev. D | Page 6 of 23
Data Sheet
ADP7142
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.
5.05
5.04
5.03
5.02
5.01
5.00
4.99
4.98
4.97
4.96
4.95
300
250
200
150
100
50
LOAD = 100µA
LOAD = 1mA
LOAD = 10mA
LOAD = 50mA
LOAD = 100mA
LOAD = 200mA
LOAD = 100µA
LOAD = 1mA
LOAD = 10mA
LOAD = 50mA
LOAD = 100mA
LOAD = 200mA
0
–40
–5
25
85
125
–40
–5
25
85
125
JUNCTION TEMPERATURE (°C)
JUNCTION TEMPERATURE (°C)
Figure 6. Output Voltage (VOUT) vs. Junction Temperature
Figure 9. Ground Current vs. Junction Temperature
5.05
200
5.04
5.03
5.02
5.01
5.00
4.99
4.98
4.97
4.96
4.95
180
160
140
120
100
80
60
40
20
0
0.1
1
10
(mA)
100
1000
0.1
1
10
(mA)
100
1000
I
I
LOAD
LOAD
Figure 7. Output Voltage (VOUT) vs. Load Current (ILOAD
)
Figure 10. Ground Current vs. Load Current (ILOAD)
5.05
5.04
5.03
5.02
5.01
5.00
4.99
4.98
4.97
4.96
4.95
300
250
200
150
100
50
LOAD = 100µA
LOAD = 1mA
LOAD = 10mA
LOAD = 50mA
LOAD = 100mA
LOAD = 200mA
LOAD = 100µA
LOAD = 1mA
LOAD = 10mA
LOAD = 50mA
LOAD = 100mA
LOAD = 200mA
0
5
10
15
20
25
(V)
30
35
40
5
10
15
20
25
(V)
30
35
40
V
V
IN
IN
Figure 8. Output Voltage (VOUT) vs. Input Voltage (VIN)
Figure 11. Ground Current vs. Input Voltage (VIN)
Rev. D | Page 7 of 23
ADP7142
Data Sheet
3.5
3.0
2.5
2.0
1.5
1.0
0.5
1000
900
800
700
600
500
400
300
200
100
0
LOAD = 5mA
V
V
V
V
V
V
= 2.7V
= 3V
= 5V
= 6V
= 10V
= 40V
IN
IN
IN
IN
IN
IN
LOAD = 10mA
LOAD = 50mA
LOAD = 100mA
LOAD = 150mA
LOAD = 200mA
0
–50
4.8
5.0
5.2
(V)
5.4
5.6
–25
0
25
50
75
100
125
V
TEMPERATURE (°C)
IN
Figure 12. Shutdown Current vs. Temperature at Various Input Voltages (VIN)
Figure 15. Ground Current vs. Input Voltage (VIN) in Dropout, VOUT = 5 V
250
3.35
LOAD = 100µA
LOAD = 1mA
LOAD = 10mA
LOAD = 50mA
LOAD = 100mA
LOAD = 200mA
200
150
100
50
3.33
3.31
3.29
3.27
3.25
0
1
10
100
1000
–40
–5
25
85
125
I
(mA)
JUNCTION TEMPERATURE (°C)
LOAD
Figure 16. Output Voltage (VOUT) vs. Junction Temperature, VOUT = 3.3 V
Figure 13. Dropout Voltage vs. Load Current (ILOAD), VOUT = 5 V
3.35
5.05
5.00
4.95
4.90
4.85
4.80
3.33
3.31
3.29
3.27
3.25
4.75
LOAD = 5mA
LOAD = 10mA
LOAD = 50mA
LOAD = 100mA
LOAD = 150mA
LOAD = 200mA
4.70
4.65
4.60
4.8
5.0
5.2
(V)
5.4 5.6
0.1
1
10
(mA)
100
1000
V
I
LOAD
IN
Figure 14. Output Voltage (VOUT) vs. Input Voltage (VIN) in Dropout, VOUT = 5 V
Figure 17. Output Voltage (VOUT) vs. Load Current (ILOAD), VOUT = 3.3 V
Rev. D | Page 8 of 23
Data Sheet
ADP7142
3.35
300
250
200
150
100
50
LOAD = 100µA
LOAD = 100µA
LOAD = 1mA
LOAD = 10mA
LOAD = 50mA
LOAD = 100mA
LOAD = 200mA
LOAD = 1mA
LOAD = 10mA
LOAD = 50mA
LOAD = 100mA
LOAD = 200mA
3.33
3.31
3.29
3.27
3.25
0
0
5
10
15
20
(V)
25
30
35
40
0
5
10
15
20
(V)
25
30
35
40
V
V
IN
IN
Figure 18. Output Voltage (VOUT) vs. Input Voltage (VIN), VOUT = 3.3 V
Figure 21. Ground Current vs. Input Voltage (VIN), VOUT = 3.3 V
300
300
250
200
150
100
50
LOAD = 100µA
LOAD = 1mA
LOAD = 10mA
LOAD = 50mA
LOAD = 100mA
250
LOAD = 200mA
200
150
100
50
0
0
1
10
100
1000
–40
–5
25
85
125
I
(mA)
JUNCTION TEMPERATURE (°C)
LOAD
Figure 19. Ground Current vs. Junction Temperature, VOUT = 3.3 V
Figure 22. Dropout Voltage vs. Load Current (ILOAD), VOUT = 3.3 V
200
180
160
140
120
100
80
3.4
3.3
3.2
3.1
3.0
60
LOAD = 5mA
LOAD = 10mA
LOAD = 50mA
LOAD = 100mA
40
2.9
20
LOAD = 150mA
LOAD = 200mA
3.7 3.9
0
0.1
2.8
3.1
1
10
(mA)
100
1000
3.3
3.5
(V)
I
V
LOAD
IN
Figure 20. Ground Current vs. Load Current (ILOAD), VOUT = 3.3 V
Figure 23. Output Voltage (VOUT) vs. Input Voltage (VIN) in Dropout,
VOUT = 3.3 V
Rev. D | Page 9 of 23
ADP7142
Data Sheet
700
600
500
400
300
200
100
0
–10
–20
–30
–40
–50
–60
–70
–80
–90
–100
LOAD = 5mA
LOAD = 10mA
LOAD = 50mA
LOAD = 100mA
LOAD = 150mA
LOAD = 200mA
10Hz
100Hz
1kHz
10kHz
100kHz
1MHz
10MHz
0
3.1
3.3
3.5
(V)
3.7
3.9
0.2
0.6
1.0
1.4
1.8
2.2
2.6
3.0
V
HEADROOM VOLTAGE (V)
IN
Figure 24. Ground Current vs. Input Voltage (VIN) in Dropout, VOUT = 3.3 V
Figure 27. Power Supply Rejection Ratio (PSRR) vs. Headroom Voltage,
VOUT = 1.8 V, for Different Frequencies
300
0
–20
–40
–60
V
V
V
V
V
= 2.7V
= 5.0V
= 10V
= 20V
= 40V
IN
IN
IN
IN
IN
250
200
150
100
50
3.0V
2.0V
1.6V
1.4V
1.2V
1.0V
800mV
700mV
600mV
500mV
–80
–100
–120
0
–40
–5
25
85
125
10
100
1k
10k
100k
1M
10M
TEMPERATURE (°C)
FREQUENCY (Hz)
Figure 28. Power Supply Rejection Ratio (PSRR) vs. Frequency, VOUT = 3.3 V, for
Various Headroom Voltages
Figure 25. Soft Start (SS) Current vs. Temperature, Multiple Input Voltages (VIN),
VOUT = 5 V
0
0
10Hz
100Hz
1kHz
10kHz
100kHz
1MHz
10MHz
3.0V
2.0V
1.6V
1.4V
1.2V
1.0V
800mV
–10
–10
–20
–20
–30
–30
700mV
600mV
–40
–50
–60
–70
–80
–90
–40
–50
–60
–70
–80
–90
–100
–100
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
1
10
100
1k
10k
100k
1M
10M
HEADROOM VOLTAGE (V)
FREQUENCY (Hz)
Figure 29. Power Supply Rejection Ratio (PSRR) vs. Headroom Voltage,
Figure 26. Power Supply Rejection Ratio (PSRR) vs. Frequency, VOUT = 1.8 V, for
Various Headroom Voltages
V
OUT = 3.3 V, for Different Frequencies
Rev. D | Page 10 of 23
Data Sheet
ADP7142
0
10k
1k
100
10
1
–20
–40
–60
3.0V
2.0V
1.6V
–80
1.4V
1.2V
1.0V
800mV
700mV
600mV
500mV
–100
–120
1
10
100
1k
10k
100k
1M
10M
10
100
1k
10k
100k
1M
10M
FREQUENCY (Hz)
FREQUENCY (Hz)
Figure 33. Output Noise Spectral Density vs. Frequency, ILOAD = 10 mA
Figure 30. Power Supply Rejection Ratio (PSRR) vs. Frequency, VOUT = 5 V, for
Various Headroom Voltages
0
100k
10Hz
100µA
100Hz
1kHz
10kHz
100kHz
1MHz
10MHz
1mA
10mA
100mA
200mA
–10
–20
10k
–30
–40
–50
–60
–70
–80
–90
1k
100
10
1
–100
1
10
100
1k
10k
100k
1M
10M
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
FREQUENCY (Hz)
HEADROOM VOLTAGE (V)
Figure 34. Output Noise Spectral Density vs. Frequency, for Different Loads
Figure 31. Power Supply Rejection Ratio (PSRR) vs. Headroom Voltage,
V
OUT = 5 V, for Different Frequencies
20
16
12
8
100k
1.8V
3.3V
5.0V
10Hz TO 100kHz
100Hz TO 100kHz
10k
1k
100
10
1
4
0
1
10
100
1k
10k
100k
1M
10M
1
10
100
1000
FREQUENCY (Hz)
LOAD CURRENT (mA)
Figure 35. Output Noise Spectral Density vs. Frequency, for Different Output
Voltages (VOUT
Figure 32. RMS Output Noise vs. Load Current (ILOAD
)
)
Rev. D | Page 11 of 23
ADP7142
Data Sheet
T
T
1
2
2
1
B
B
W
CH1 200mA Ω
CH2 20mV
M20µs
A
CH1
1000mA
W
B
B
CH1 1V
CH2 2mV
M4µs
10.2%
A
CH4
1.84V
W
W
T
10.2%
T
Figure 36. Load Transient Response, ILOAD = 1 mA to 200 mA,
VOUT = 5 V, VIN = 7 V, CH1 Load Current (ILOAD), CH2 VOUT
Figure 39. Line Transient Response, ILOAD = 200 mA,
VOUT = 3.3 V, CH1 VIN, CH2 VOUT
T
T
1
2
1
2
B
B
B
B
CH1 2V
CH2 2.0mV
M4µs
10.2%
A
CH4
1.84V
CH1 200mA
Ω
CH2 20mV
M20µs
W
A
CH1
84mA
W
W
W
T
T
10.2%
Figure 37. Line Transient Response, ILOAD = 200 mA,
VOUT = 5 V, CH1 VIN, CH2 VOUT
Figure 40. Load Transient Response, ILOAD = 1 mA to 200 mA,
VOUT = 1.8 V, VIN = 3 V, CH1 Load Current (ILOAD), CH2 VOUT
T
T
1
2
1
2
B
B
W
CH1 200mA Ω
CH2 20mV
M20µs
A
CH1
148mA
W
B
CH1 1V
CH2 5mV
M4.0µs
93.4%
A
CH4
2.08V
W
T
10.4%
T
Figure 38. Load Transient Response, ILOAD = 1 mA to 200 mA,
OUT = 3.3 V, VIN = 5 V, CH1 Load Current (ILOAD), CH2 VOUT
Figure 41. Line Transient Response, ILOAD = 200 mA,
OUT = 1.8 V, CH1 VIN, CH2 VOUT
V
V
Rev. D | Page 12 of 23
Data Sheet
ADP7142
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 μA of quiescent current
(typical) at full load makes the ADP7142 ideal for portable
equipment. Typical shutdown current consumption is less than
3 μA at room temperature.
The ADP7142 is available in 16 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:
V
OUT = 5 V(1 + R1/R2)
(3)
Optimized for use with small 2.2 µF ceramic capacitors, the
ADP7142 provides excellent transient performance.
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.
VIN
VOUT
SENSE/
ADJ
SHORT-CIRCUIT,
THERMAL
PROTECTION
GND
ADP7142
V
= 7V
V
= 6V
OUT
IN
VIN
VOUT
REFERENCE
C
2.2µF
R1
C
OUT
2.2µF
IN
2kΩ
SENSE/ADJ
R2
10kΩ
EN
SHUTDOWN
ON
Figure 42. Internal Block Diagram
EN
SS
GND
C
1nF
SS
OFF
Internally, the ADP7142 consists of a reference, an error amplifier, a
feedback voltage divider, 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.
Figure 43. Typical Adjustable Output Voltage Application Schematic
It is recommended that the R2 value be less than 200 kΩ to
minimize errors in the output voltage caused by the SENSE/ADJ
pin input current. For example, when R1 and R2 each equal 200 kΩ
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.
Rev. D | Page 13 of 23
ADP7142
Data Sheet
APPLICATIONS INFORMATION
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.
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
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.
2.5
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.
2.0
1.5
1.0
0.5
0
T
0
2
4
6
8
10
12
DC BIAS VOLTAGE (V)
1
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.
2
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.
B
B
CH1 200mA Ω
CH2 20mV
M20µs A CH1
T 10.2%
100mA
W
W
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
Figure 44. Output Transient Response, VOUT = 5 V, COUT = 2.2 µF, CH1 Load
Current, CH2 VOUT
Input Bypass Capacitor
C
BIAS is 2.09 μF at 5 V, as shown in Figure 45.
These values in Equation 1 yield
EFF = 2.09 μF × (1 − 0.15) × (1 − 0.1) = 1.59 μF
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.
C
(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.
Input and Output Capacitor Properties
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.
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-
Rev. D | Page 14 of 23
Data Sheet
ADP7142
PROGRAMABLE PRECISION ENABLE
SOFT START
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.
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 μs 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.
6
3.5
V
V
V
V
EN
IN
IN
IN
= 1.8V
= 3.3V
= 5.0V
3.0
2.5
2.0
1.5
1.0
5
4
3
2
1
0
0.5
–40°C
+25°C
+125°C
0
1.05
1.10
1.15
1.20
1.25
1.30
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
V
(V)
EN
TIME (ms)
Figure 46. Typical VOUT Response to EN Pin Operation
Figure 48. Typical Start-Up Behavior
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
An external capacitor connected to the SS pin determines the
soft start time. The SS pin can be left open for a typical 380 μs
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:
R
R
EN2 = nominally 10 kΩ to 100 kΩ
(6)
(7)
SSTIME (sec) = tSTARTUP (0 pF) + (0.6 × CSS)/ISS
where:
STARTUP (at 0 pF) is the start-up time at CSS = 0 pF (typically 380 ꢀs).
(8)
EN1 = REN2 × (VIN − 1.2 V)/1.2 V
where:
t
VIN is the desired turn-on voltage.
CSS is the soft start capacitor (F).
The hysteresis voltage increases by the factor (REN1 + REN2)/ REN2
.
ISS is the soft start current (typically 1.15 ꢀA).
For the example shown in Figure 47, the enable threshold is 3.6 V
3.5
with a hysteresis of 300 mV.
3.0
2.5
2.0
1.5
1.0
0.5
0
ADP7142
V
= 8V
V
= 6V
IN
OUT
VIN
VOUT
R1
C
C
OUT
2.2µF
IN
10kΩ
2.2µF
SENSE/ADJ
R2
20kΩ
R
EN1
ON
200kꢀ
EN
GND
R
OFF
EN2
100kꢀ
V
EN
NO SS CAP
1nF
2nF
4.7nF
6.8nF
10nF
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.
0
1
2
3
4
5
6
7
8
9
10
TIME (ms)
Figure 49. Typical Soft Start Behavior, Different CSS
Rev. D | Page 15 of 23
ADP7142
Data Sheet
Measured rms noise of the adjustable LDO without noise
reduction is 70 ꢀV rms
Measured rms noise of the adjustable LDO with noise
reduction is 12 ꢀV rms
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):
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 ꢀV rms vs. 110 ꢀV rms.
V
OUT = 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.
100k
12V NOISE REDUCTION
12V NO NOISE REDUCTION
6V NOISE REDUCTION
10k
1k
6V NO NOISE REDUCTION
100
10
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.
1
1
10
100
1k
10k
100k
1M
10M
V
= 12V
V
= 14V
VIN
VOUT
OUT
IN
R1
91kꢀ
C
2.2µF
C
FREQUENCY (Hz)
IN
OUT
2.2µF
C
1µF
NR
SENSE/ADJ
Figure 51. 6 V and 12 V Output Voltage with and Without Noise Reduction
Network
R
1kꢀ
NR
ON
200kꢀ
100kꢀ
R2
10kꢀ
EN/
UVLO
OFF
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.
GND
Figure 50. Noise Reduction Modification
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:
The noise of the adjustable LDO is found by using the following
formula, assuming the noise of a fixed output LDO is
approximately 11 μV.
Noise = 11 μV × (RPAR + R2)/R2
(9)
SSNRTIME (sec) = 5.5 × CNR × (RNR + R1)
where RPAR is a parallel combination of R1 and RNR.
For a CNR, RNR, and R1 combination of 1 ꢀF, 1 kΩ, and 91 kΩ 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.
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)
Rev. D | Page 16 of 23
Data Sheet
ADP7142
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.
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 400 mA (typical). When the output load
exceeds 400 mA, the output voltage is reduced to maintain a
constant current limit.
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.
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.
Table 6. Typical θJA Values
θ
JA (°C/W)
Copper Size (mm2)
LFCSP
182.8
N/A2
142.6
83.9
SOIC
N/A2
181.4
145.4
89.3
TSOT
N/A2
152
146
131
251
50
100
500
1000
6400
Consider the case where a hard short from VOUT to ground
occurs. At first, the ADP7142 current limits, so that only 400 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 400 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 400 mA and 0 mA that continues as
long as the short remains at the output.
71.7
57.4
77.5
63.2
N/A2
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
8-Lead SOIC
5-Lead TSOT
24
38.8
43
To calculate the junction temperature of the ADP7142, use
Equation 1:
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.
TJ = TA + (PD × θJA)
where:
THERMAL CONSIDERATIONS
TA is the ambient temperature.
PD is the power dissipation in the die, given by
In applications with a low input-to-output voltage differential,
the ADP7142 does not dissipate much heat. However, in
applications 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.
PD = [(VIN − VOUT) × ILOAD] + (VIN × IGND
where:
IN and VOUT are input and output voltages, respectively.
)
(10)
V
I
LOAD is the load current.
I
GND is the ground current.
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.
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.
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
Rev. D | Page 17 of 23
ADP7142
Data Sheet
140
120
100
80
145
135
125
115
105
95
85
60
75
65
40
T
T
T
T
T
= 25°C
= 50°C
= 65°C
= 85°C
MAX
55
B
B
B
B
J
2
6400mm
45
2
500mm
20
2
25mm
35
T
MAX
J
25
0
0
0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4
TOTAL POWER DISSIPATION (W)
0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
TOTAL POWER DISSIPATION (W)
Figure 52. LFCSP, TA = 25°C
Figure 55. SOIC, TA = 25°C
140
130
120
110
100
90
140
130
120
110
100
90
80
80
70
70
2
2
6400mm
6400mm
2
2
500mm
500mm
60
2
60
2
25mm
50mm
T
MAX
1.6
T
MAX
1.2
J
J
50
50
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.8
0
0.2
0.4
0.6
0.8
1.0
TOTAL POWER DISSIPATION (W)
TOTAL POWER DISSIPATION (W)
Figure 53. LFCSP, TA = 50°C
Figure 56. SOIC, TA = 50°C
140
130
120
110
100
90
145
135
125
115
105
95
80
85
70
2
6400mm
2
6400mm
2
500mm
2
500mm
75
60
2
2
25mm
50mm
T
MAX
1.6
J
T MAX
J
50
65
0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.8
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
TOTAL POWER DISSIPATION (W)
TOTAL POWER DISSIPATION (W)
Figure 54. LFCSP, TA = 85°C
Figure 57. SOIC, TA = 85°C
Rev. D | Page 18 of 23
Data Sheet
ADP7142
145
135
125
115
105
95
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.
140
120
100
80
85
75
65
55
2
2
500mm
100mm
50mm
45
60
2
35
T
MAX
J
40
25
T
T
T
T
T
= 25°C
= 50°C
= 65°C
= 85°C
MAX
B
B
B
B
J
0
0
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
TOTAL POWER DISSIPATION (W)
20
0
Figure 58. TSOT, TA = 25°C
140
130
120
110
100
90
0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
TOTAL POWER DISSIPATION (W)
Figure 61. LFCSP Junction Temperature Rise, Different Board Temperatures
140
120
100
80
80
70
2
2
500mm
100mm
50mm
60
60
2
T
MAX
J
40
50
T
T
T
T
T
= 25°C
= 50°C
= 65°C
= 85°C
MAX
B
B
B
B
J
0.1
0.2
0.3
0.4
0.5
0.6
0.7
TOTAL POWER DISSIPATION (W)
20
0
Figure 59. TSOT, TA = 50°C
145
135
125
115
105
95
0
0.5
1.0
1.5
2.0
2.5
3.0
TOTAL POWER DISSIPATION (W)
Figure 62. SOIC Junction Temperature Rise, Different Board Temperatures
140
120
100
80
85
2
2
500mm
100mm
50mm
60
75
2
T
MAX
J
40
65
T
T
T
T
T
= 25°C
= 50°C
= 65°C
= 85°C
MAX
B
B
B
B
J
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
TOTAL POWER DISSIPATION (W)
20
0
Figure 60. TSOT, TA = 85°C
0
0.5
1.0
1.5
2.0
2.5
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.
TOTAL POWER DISSIPATION (W)
Figure 63. TSOT Junction Temperature Rise, Different Board Temperatures
TJ = TB + (PD × ΨJB)
Rev. D | Page 19 of 23
ADP7142
Data Sheet
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.
Figure 64. Example LFCSP PCB Layout
Figure 65. Example SOIC PCB Layout
Rev. D | Page 20 of 23
Data Sheet
ADP7142
Figure 66. Example TSOT PCB Layout
Table 8. Recommended LDOs for Very Low Noise Operation
Noise
(Fixed)
10 Hz to
100 kHz
(µV rms)
VOUT
Adjust
I
Q at
IGND-SD
Max
(µA)
PSRR
100 kHz
(dB)
Device
Number
VIN
VOUT
IOUT
(mA)
IOUT
(µA)
Soft
Start
PSRR
1 MHz
Range (V) Fixed (V) (V)
PGOOD
Package
ADP7102
ADP7104
ADP7105
ADP7118
3.3 to 20
3.3 to 20
3.3 to 20
2.7 to 20
1.5 to 9
1.22 to
19
300
500
500
200
750
900
900
160
75
75
75
10
No
No
Yes
Yes
Yes
15
15
15
11
60
60
60
68
40 dB
40 dB
40 dB
50 dB
3 × 3mm
8-lead LFCSP,
8-lead SOIC
1.5 to 9
1.22 to
19
Yes
Yes
No
3 × 3mm
8-lead LFCSP,
8-lead SOIC
1.8, 3.3, 5 1.22 to
19
3 × 3mm
8-lead LFCSP,
8-lead SOIC
1.2 to 5
1.2 to 19
2 × 2mm
6-lead LFCSP,
8-lead SOIC,
5-lead TSOT
ADP7142
ADP7182
2.7 to 40
1.2 to 5
1.2 to 39
200
160
10
−8
Yes
No
No
No
11
18
68
45
50 dB
45 dB
2 × 2mm
6-lead LFCSP,
8-lead SOIC,
5-lead TSOT
−2.7 to
−28
−1.8 to
−5
−1.22 to
−27
−200
−650
2 × 2mm
6-lead LFCSP,
3 × 3mm
8-lead LFCSP,
5-lead TSOT
Table 9. Related Devices
Model
Input Voltage (V)
2.7 to 20
2.7 to 20
2.7 to 20
2.7 to 20
Output Current (mA)
Package
ADP7118CP
ADP7118RD
ADP7118UJ
ADP7112CB
200
200
200
200
6-Lead LFCSP
8-Lead SOIC
5-Lead TSOT
4-Lead WLCSP
Rev. D | Page 21 of 23
ADP7142
Data Sheet
OUTLINE DIMENSIONS
DETAIL A
(JEDEC 95)
1.70
1.60
1.50
2.10
2.00 SQ
1.90
0.65 BSC
6
4
PIN 1 INDEX
EXPOSED
PAD
1.10
1.00
0.90
AREA
0.425
0.350
0.275
0.15 MIN
PIN 1
3
1
S
TOP VIEW
INDIC ATOR AREA OPTION
(SEE DETAIL A)
BOTTOM VIEW
FOR PROPER CONNECTION OF
THE EXPOSED PAD, REFER TO
THE PIN CONFIGURATION AND
FUNCTION DESCRIPTIONS
0.60
0.55
0.50
0.05 MAX
0.02 NOM
SECTION OF THIS DATA SHEET.
SEATING
PLANE
0.35
0.30
0.25
0.20 REF
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
5.00
4.90
4.80
2.29
0.356
5
4
6.20
6.00
5.80
8
1
4.00
3.90
3.80
2.29
0.457
FOR PROPER CONNECTION OF
THE EXPOSED PAD, REFER TO
THE PIN CONFIGURATION AND
FUNCTION DESCRIPTIONS
BOTTOM VIEW
45°
1.27 BSC
3.81 REF
TOP VIEW
SECTION OF THIS DATA SHEET.
1.65
1.25
1.75
1.35
0.50
0.25
0.25
0.17
0.10 MAX
0.05 NOM
SEATING
PLANE
8°
0°
0.51
0.31
1.04 REF
1.27
0.40
COPLANARITY
0.10
COMPLIANT TO JEDEC STANDARDS MS-012-AA
Figure 68. 8-Lead Standard Small Outline Package, with Exposed Pad [SOIC_N_EP]
Narrow Body
(RD-8-1)
Dimensions shown in millimeters
Rev. D | Page 22 of 23
Data Sheet
ADP7142
3.05
2.90
2.75
TOP VIEW
5
1
4
3
3.05
2.80
2.55
1.75
1.60
1.45
2
0.95 BSC
1.90 REF
0.90
0.70
SIDE VIEW
END VIEW
1.00 MAX
0.20
0.08
8°
4°
0°
SEATING
PLANE
0.10 MAX
0.50
0.30
0.60
0.45
0.30
COMPLIANT TO JEDEC STANDARDS MO-193-AB
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
6-Lead LFCSP
6-Lead LFCSP
6-Lead LFCSP
6-Lead LFCSP
Package Option Branding
ADP7142ACPZN-R7
ADP7142ACPZN1.8-R7
ADP7142ACPZN2.5-R7
ADP7142ACPZN3.3-R7
ADP7142ACPZN5.0-R7
ADP7142ARDZ
ADP7142ARDZ-R7
ADP7142ARDZ-1.8
ADP7142ARDZ-1.8-R7
ADP7142ARDZ-2.5
ADP7142ARDZ-2.5-R7
ADP7142ARDZ-3.3
ADP7142ARDZ-3.3-R7
ADP7142ARDZ-5.0
ADP7142ARDZ-5.0-R7
ADP7142AUJZ-R2
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
−40°C to +125°C
Adjustable (1.2 V)
1.8
2.5
3.3
CP-6-3
CP-6-3
CP-6-3
CP-6-3
CP-6-3
RD-8-1
RD-8-1
RD-8-1
RD-8-1
RD-8-1
RD-8-1
RD-8-1
RD-8-1
RD-8-1
RD-8-1
UJ-5
LP4
LP5
LP7
LP6
LP8
5
6-Lead LFCSP
Adjustable (1.2 V)
Adjustable (1.2 V)
1.8
1.8
2.5
2.5
3.3
3.3
8-Lead SOIC_N_EP
8-Lead SOIC_N_EP
8-Lead SOIC_N_EP
8-Lead SOIC_N_EP
8-Lead SOIC_N_EP
8-Lead SOIC_N_EP
8-Lead SOIC_N_EP
8-Lead SOIC_N_EP
8-Lead SOIC_N_EP
8-Lead SOIC_N_EP
5-Lead TSOT
5
5
Adjustable (1.2 V)
Adjustable (1.2 V)
1.8
2.5
3.3
5
LP4
LP4
LP5
LP7
LP6
LP8
ADP7142AUJZ-R7
5-Lead TSOT
5-Lead TSOT
5-Lead TSOT
5-Lead TSOT
UJ-5
UJ-5
UJ-5
UJ-5
ADP7142AUJZ-1.8-R7
ADP7142AUJZ-2.5-R7
ADP7142AUJZ-3.3-R7
ADP7142AUJZ-5.0-R7
ADP7142UJ-EVALZ
ADP7142CP-EVALZ
ADP7142RD-EVALZ
5-Lead TSOT
UJ-5
3.3
3.3
3.3
TSOT Evaluation Board
LFCSP Evaluation Board
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.
©2014–2017 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D11848-0-11/17(D)
Rev. D | Page 23 of 23
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