FEATURES
TYPICAL APPLICATION CIRCUITS
VIN = 8V
CIN +
1µF
VIN
VOUT
VOUT = 5V
+ COUT
1µF
SENSE
R1
100kΩ
ON
OFF
R2
100kΩ
RPG
100kΩ
EN/
UVLO
PG
PG
GND
09506-001
Input voltage range: 3.3 V to 20 V
Maximum output current: 300 mA
Low noise: 15 µV rms for fixed output versions
PSRR performance of 60 dB at 10 kHz, VOUT = 3.3 V
Reverse current protection
Low dropout voltage: 200 mV at 300 mA load
Initial accuracy: ±0.8%
Accuracy over line, load, and temperature: −2%, +1%
Low quiescent current (VIN = 5 V), IGND = 750 μA with 300 mA
load
Low shutdown current: 40 µA at VIN = 12 V
Stable with small 1 µF ceramic output capacitor
7 fixed output voltage options: 1.5 V, 1.8 V, 2.5 V, 3 V, 3.3 V,
5 V, and 9 V
Adjustable output from 1.22 V to VIN – VDO
Foldback current limit and thermal overload protection
User programmable precision UVLO/enable
Power good indicator
8-lead LFCSP and 8-lead SOIC packages
Figure 1. ADP7102 with Fixed Output Voltage, 5 V
VIN = 8V
CIN +
1µF
VIN
VOUT
ADJ
ON
R3
100kΩ
OFF
R4
100kΩ
R1
40.2kΩ
R2
13kΩ
EN/
UVLO
PG
VOUT = 5V
+ COUT
1µF
RPG
100kΩ
PG
GND
09506-002
Data Sheet
20 V, 300 mA, Low Noise, CMOS LDO
ADP7102
Figure 2. ADP7102 with Adjustable Output Voltage, 5 V
APPLICATIONS
Regulation to noise sensitive applications: ADC, DAC
circuits, precision amplifiers, high frequency oscillators,
clocks, and PLLs
Communications and infrastructure
Medical and healthcare
Industrial and instrumentation
GENERAL DESCRIPTION
The ADP7102 is a CMOS, low dropout linear regulator that
operates from 3.3 V to 20 V and provides up to 300 mA of
output current. This high input voltage LDO is ideal for
regulation of high performance analog and mixed signal
circuits operating from 19 V to 1.22 V rails. Using an
advanced proprietary architecture, it provides high power
supply rejection, low noise, and achieves excellent line and
load transient response with just a small 1 µF ceramic
output capacitor.
The ADP7102 is available in 7 fixed output voltage options and
an adjustable version, which allows output voltages that range
from 1.22 V to VIN − VDO via an external feedback divider.
The ADP7102 output noise voltage is 15 μV rms and is independent of the output voltage. A digital power good output
allows power system monitors to check the health of the output
voltage. A user programmable precision undervoltage lockout
function facilitates sequencing of multiple power supplies.
The ADP7102 is available in 8-lead, 3 mm × 3 mm LFCSP
and 8-lead SOIC packages. The LFCSP offers a very compact
solution and also provides excellent thermal performance for
applications requiring up to 300 mA of output current in a
small, low-profile footprint.
Rev. A
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
www.analog.com
Fax: 781.461.3113
©2011 Analog Devices, Inc. All rights reserved.
ADP7102
Data Sheet
TABLE OF CONTENTS
Features .............................................................................................. 1
Theory of Operation ...................................................................... 17
Applications ....................................................................................... 1
Applications Information .............................................................. 18
Typical Application Circuits............................................................ 1
Capacitor Selection .................................................................... 18
General Description ......................................................................... 1
Programable Undervoltage Lockout (UVLO)........................... 19
Revision History ............................................................................... 2
Power Good Feature .................................................................. 20
Specifications..................................................................................... 3
Noise Reduction of the Adjustable ADP7102 ........................ 20
Input and Output Capacitor, Recommended Specifications .. 4
Current Limit and Thermal Overload Protection ................. 21
Absolute Maximum Ratings ............................................................ 5
Thermal Considerations............................................................ 21
Thermal Data ................................................................................ 5
Printed Circuit Board Layout Considerations ............................ 24
ESD Caution .................................................................................. 5
Outline Dimensions ....................................................................... 25
Pin Configurations and Function Descriptions ........................... 6
Ordering Guide .......................................................................... 26
Typical Performance Characteristics ............................................. 7
REVISION HISTORY
11/11—Rev. 0 to Rev. A
Changes to Figure 50 ...................................................................... 14
10/11—Revision 0: Initial Version
Rev. A | Page 2 of 28
Data Sheet
ADP7102
SPECIFICATIONS
VIN = (VOUT + 1 V) or 3.3 V (whichever is greater), EN = VIN, IOUT = 10 mA, CIN = COUT = 1 µF, TA = 25°C, unless otherwise noted.
Table 1.
Parameter
INPUT VOLTAGE RANGE
OPERATING SUPPLY CURRENT
Symbol
VIN
IGND
SHUTDOWN CURRENT
IGND-SD
INPUT REVERSE CURRENT
IREV-INPUT
OUTPUT VOLTAGE ACCURACY
Fixed Output Voltage Accuracy
Adjustable Output Voltage
Accuracy
VOUT
VADJ
LINE REGULATION
LOAD REGULATION 1
∆VOUT/∆VIN
∆VOUT/∆IOUT
ADJ INPUT BIAS CURRENT
ADJI-BIAS
SENSE INPUT BIAS CURRENT
SENSEI-BIAS
DROPOUT VOLTAGE 2
VDROPOUT
START-UP TIME 3
CURRENT-LIMIT THRESHOLD 4
PG OUTPUT LOGIC LEVEL
PG Output Logic High
PG Output Logic Low
PG OUTPUT THRESHOLD
Output Voltage Falling
Output Voltage Rising
THERMAL SHUTDOWN
Thermal Shutdown Threshold
Thermal Shutdown Hysteresis
tSTART-UP
ILIMIT
PGHIGH
PGLOW
Conditions
IOUT = 100 µA, VIN = 10 V
IOUT = 100 µA, VIN = 10 V, TJ = −40°C to +125°C
IOUT = 10 mA, VIN = 10 V
IOUT = 10 mA, VIN = 10 V, TJ = −40°C to +125°C
IOUT = 150 mA, VIN = 10 V
IOUT = 150 mA, VIN = 10 V, TJ = −40°C to +125°C
IOUT = 300 mA, VIN = 10 V
IOUT = 300 mA, VIN = 10 V, TJ = −40°C to +125°C
EN = GND, VIN = 12 V
EN = GND, VIN = 12 V, TJ = −40°C to +125°C
EN = GND, VIN = 0 V, VOUT = 20 V
EN = GND, VIN = 0 V, VOUT = 20 V, TJ = −40°C to +125°C
Max
20
5
Unit
V
µA
µA
µA
µA
µA
µA
µA
µA
µA
µA
µA
µA
+0.8
+1
%
%
1.23
V
1.232
V
+0.015
10
%/V
%/A
%/A
nA
1
μA
900
450
1050
650
1250
750
1400
40
75
0.3
–0.8
–2
1 mA < IOUT < 300 mA, VIN = (VOUT + 1 V) to 20 V,
TJ = −40°C to +125°C
VIN = (VOUT + 1 V) to 20 V, TJ = −40°C to +125°C
IOUT = 1 mA to 300 mA
IOUT = 1 mA to 300 mA, TJ = −40°C to +125°C
1 mA < IOUT < 300 mA, VIN = (VOUT + 1 V) to 20 V,
ADJ connected to VOUT
1 mA < IOUT < 300 mA, VIN = (VOUT + 1 V) to 20 V,
SENSE connected to VOUT, VOUT = 1.5 V
IOUT = 10 mA
IOUT = 10 mA, TJ = −40°C to +125°C
IOUT = 150 mA
IOUT = 150 mA, TJ = −40°C to +125°C
IOUT = 300 mA
IOUT = 300 mA, TJ = −40°C to +125°C
VOUT = 5 V
1.196
1.21
1.22
−0.015
0.2
1.0
20
750
mV
mV
mV
mV
mV
mV
µs
mA
0.4
V
V
40
100
175
200
325
450
IOH < 1 µA
IOL < 2 mA
Typ
400
IOUT = 10 mA
1 mA < IOUT < 300 mA, VIN = (VOUT + 1 V) to 20 V,
TJ = −40°C to +125°C
IOUT = 10 mA
800
575
1.0
PGFALL
PGRISE
TSSD
TSSD-HYS
Min
3.3
TJ rising
Rev. A | Page 3 of 28
−9.2
−6.5
%
%
150
15
°C
°C
ADP7102
Data Sheet
Parameter
PROGRAMMABLE EN/UVLO
UVLO Threshold rising
UVLO Threshold falling
Symbol
Conditions
Min
Typ
Max
Unit
UVLORISE
UVLOFALL
1.18
1.23
1.13
1.28
V
V
UVLO Hysteresis Current
Enable Pulldown Current
INPUT VOLTAGE
Start Threshold
Shutdown Threshold
Hysteresis
OUTPUT NOISE
UVLOHYS
I EN-IN
3.3 V ≤ V IN ≤ 20 V, T J = −40°C to +125°C
3.3 V ≤ V IN ≤ 20 V, T J = −40°C to +125°C, 10 kΩ
in series with enable pin
VEN > 1.25 V, TJ = −40°C to +125°C
EN = VIN
7.5
9.8
500
12
µA
nA
VSTART
VSHUTDOWN
TJ = −40°C to +125°C
TJ = −40°C to +125°C
3.2
OUTNOISE
10 Hz to 100 kHz, VIN = 5.5 V, VOUT = 1.8 V
10 Hz to 100 kHz, VIN = 6.3 V, VOUT = 3.3 V
10 Hz to 100 kHz, VIN = 8 V, VOUT = 5 V
10 Hz to 100 kHz, VIN = 12 V, VOUT = 9 V
10 Hz to 100 kHz, VIN = 5.5 V, VOUT = 1.5 V,
adjustable mode
10 Hz to 100 kHz, VIN = 12 V, VOUT = 5 V,
adjustable mode
10 Hz to 100 kHz, VIN = 18 V, VOUT = 15 V,
adjustable mode
100 kHz, VIN = 4.3 V, VOUT = 3.3 V
100 kHz, VIN = 6 V, VOUT = 5 V
10 kHz, VIN = 4.3 V, VOUT = 3.3 V
10 kHz, VIN = 6 V, VOUT = 5 V
100 kHz, VIN = 3.3 V, VOUT = 1.8 V, adjustable mode
100 kHz, VIN = 6 V, VOUT = 5 V, adjustable mode
100 kHz, VIN = 16 V, VOUT = 15 V, adjustable mode
10 kHz, VIN = 3.3 V, VOUT = 1.8 V, adjustable mode
10 kHz, VIN = 6 V, VOUT = 5 V, adjustable mode
10 kHz, VIN = 16 V, VOUT = 15 V, adjustable mode
250
15
15
15
15
18
V
V
mV
µV rms
µV rms
µV rms
µV rms
µV rms
30
µV rms
65
µV rms
50
50
60
60
50
60
60
60
80
80
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
POWER SUPPLY REJECTION RATIO
PSRR
2.45
Based on an end-point calculation using 1 mA and 300 mA loads. See Figure 6 for typical load regulation performance for loads less than 1 mA.
Dropout voltage is defined as the input-to-output voltage differential when the input voltage is set to the nominal output voltage. This applies only for output
voltages above 3.0 V.
3
Start-up time is defined as the time between the rising edge of EN to VOUT 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.
1
2
INPUT AND OUTPUT CAPACITOR, RECOMMENDED SPECIFICATIONS
Table 2.
Parameter
Minimum Input and Output Capacitance 1
Capacitor ESR
1
Symbol
CMIN
RESR
Conditions
TA = −40°C to +125°C
TA = −40°C to +125°C
Min
0.7
0.001
Typ
Max
0.2
Unit
µF
Ω
The minimum input and output capacitance should be greater than 0.7 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;
Y5V and Z5U capacitors are not recommended for use with any LDO.
Rev. A | Page 4 of 28
Data Sheet
ADP7102
ABSOLUTE MAXIMUM RATINGS
Table 3.
Parameter
VIN to GND
VOUT to GND
EN/UVLO to GND
PG to GND
SENSE/ADJ to GND
Storage Temperature Range
Operating Junction Temperature Range
Operating Ambient Temperature Range
Soldering Conditions
Rating
–0.3 V to +22 V
–0.3 V to +20 V
–0.3 V to VIN
–0.3 V to VIN
–0.3 V to VOUT
–65°C to +150°C
–40°C to +125°C
–40°C to +85°C
JEDEC J-STD-020
Stresses above those listed under absolute maximum ratings
may cause permanent damage to the device. This is a stress
rating only and functional operation of the device at these or
any other conditions above those indicated in the operational
section of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect
device reliability.
THERMAL DATA
Absolute maximum ratings apply individually only, not in
combination. The ADP7102 can be damaged when the junction
temperature limit is 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 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 (TJ) of
the device is dependent on the ambient temperature (TA), the
power dissipation of the device (PD), and the junction-toambient thermal resistance of the package (θJA).
Maximum junction temperature (TJ) is calculated from the
ambient temperature (TA) and power dissipation (PD) using the
formula
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 in. × 3 in. circuit
board. See JESD51-7 and JESD51-9 for detailed information on
the board construction. For additional information, see the
AN-617 Application Note, MicroCSP™ Wafer Level Chip Scale
Package, available at www.analog.com.
ΨJB is the junction-to-board thermal characterization parameter
with units of °C/W. The package’s ΨJB 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 junction
temperature (TJ) is calculated from the board temperature (TB)
and power dissipation (PD) using the formula
TJ = TB + (PD × ΨJB)
See JESD51-8 and JESD51-12 for more detailed information
about ΨJB.
Thermal Resistance
θJA and ΨJB are specified for the worst-case conditions, that is, a
device soldered in a circuit board for surface-mount packages.
θJC is a parameter for surface-mount packages with top
mounted heatsinks. θJC is presented here for reference only.
Table 4. Thermal Resistance
Package Type
8-Lead LFCSP
8-Lead SOIC
ESD CAUTION
TJ = TA + (PD × θJA)
Junction-to-ambient thermal resistance (θJA) of the package is
based on modeling and calculation using a 4-layer board. The
junction-to-ambient thermal resistance is highly dependent on
the application and board layout. In applications where high
maximum power dissipation exists, close attention to thermal
Rev. A | Page 5 of 28
θJA
40.1
48.5
θJC
27.1
58.4
ΨJB
17.2
31.3
Unit
°C/W
°C/W
ADP7102
Data Sheet
PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS
8 VIN
GND 3
TOP VIEW
(Not to Scale)
NC 4
VOUT 1
7 PG
SENSE/ADJ 2
5 EN/UVLO
NOTES
1. NC = NO CONNECT. DO NOT CONNECT TO
THIS PIN.
2. IT IS HIGHLY RECOMMENDED THAT THE
EXPOSED PAD ON THE BOTTOM OF THE
PACKAGE BE CONNECTED TO THE GROUND
PLANE ON THE BOARD.
ADP7102
8
VIN
7
PG
TOP VIEW
GND 3 (Not to Scale) 6 GND
5 EN/UVLO
NC 4
6 GND
NOTES
1. NC = NO CONNECT. DO NOT CONNECT TO
THIS PIN.
2. IT IS HIGHLY RECOMMENDED THAT THE
EXPOSED PAD ON THE BOTTOM OF THE
PACKAGE BE CONNECTED TO THE GROUND
PLANE ON THE BOARD.
09506-003
ADP7102
Figure 3. LFCSP Package
09506-104
VOUT 1
SENSE/ADJ 2
Figure 4. Narrow Body SOIC Package
Table 5. Pin Function Descriptions
Pin No.
1
2
Mnemonic
VOUT
SENSE/ADJ
3
4
5
GND
NC
EN/UVLO
6
7
GND
PG
8
VIN
EPAD
Description
Regulated Output Voltage. Bypass VOUT to GND with a 1 µF or greater capacitor.
Sense (SENSE). Measures the actual output voltage at the load and feeds it to the error amplifier.
Connect SENSE as close as possible to the load to minimize the effect of IR drop between the
regulator output and the load. This function applies to fixed voltages only.
Adjust Input (ADJ). An external resistor divider sets the output voltage. This function applies to
adjustable voltages only.
Ground.
Do Not Connect to this Pin.
Enable Input (EN). Drive EN high to turn on the regulator; drive EN low to turn off the regulator.
For automatic startup, connect EN to VIN.
Programmable Undervoltage Lockout (UVLO). When the programmable UVLO function is used,
the upper and lower thresholds are determined by the programming resistors.
Ground.
Power Good. This open-drain output requires an external pull-up resistor to VIN or VOUT. If the
part is in shutdown, current limit, thermal shutdown, or falls below 90% of the nominal output
voltage, PG immediately transitions low. If the power good function is not used, the pin may be
left open or connected to ground.
Regulator Input Supply. Bypass VIN to GND with a 1 µF or greater capacitor.
Exposed Pad. Exposed paddle on the bottom of the package. The EPAD enhances thermal
performance and is electrically connected to GND inside the package. It is highly recommended
that the EPAD be connected to the ground plane on the board.
Rev. A | Page 6 of 28
Data Sheet
ADP7102
TYPICAL PERFORMANCE CHARACTERISTICS
VIN = 5 V, VOUT = 3.3 V, IOUT = 1 mA, CIN = COUT = 1 µF, TA = 25°C, unless otherwise noted.
3.35
LOAD = 100µA
LOAD = 1mA
LOAD = 10mA
LOAD = 100mA
LOAD = 300mA
800
700
GROUND CURRENT (µA)
3.33
VOUT (V)
900
LOAD = 100µA
LOAD = 1mA
LOAD = 10mA
LOAD = 100mA
LOAD = 300mA
3.31
3.29
600
500
400
300
200
3.27
100
–5°C
25°C
85°C
125°C
0
TJ (°C)
–40°C
–5°C
25°C
85°C
09506-007
–40°C
09506-004
3.25
125°C
TJ (°C)
Figure 5. Output Voltage vs. Junction Temperature
Figure 8. Ground Current vs. Junction Temperature
3.35
700
600
GROUND CURRENT (µA)
VOUT (V)
3.33
3.31
3.29
500
400
300
200
3.27
10
100
1000
ILOAD (mA)
0
0.1
1000
20
900
LOAD = 100µA
LOAD = 1mA
LOAD = 10mA
LOAD = 100mA
LOAD = 300mA
800
GROUND CURRENT (µA)
700
3.31
3.29
600
500
400
300
200
3.27
100
3.25
4
6
8
10
12
14
16
VIN (V)
18
20
0
09506-006
VOUT (V)
100
Figure 9. Ground Current vs. Load Current
LOAD = 100µA
LOAD = 1mA
LOAD = 10mA
LOAD = 100mA
LOAD = 300mA
3.33
10
ILOAD (mA)
Figure 6. Output Voltage vs. Load Current
3.35
1
09506-008
1
09506-005
3.25
0.1
09506-009
100
4
6
8
10
12
14
16
18
VIN (V)
Figure 10. Ground Current vs. Input Voltage
Figure 7. Output Voltage vs. Input Voltage
Rev. A | Page 7 of 28
ADP7102
100
80
60
40
1000
–25
0
25
50
75
100
125
TEMPERATURE (°C)
LOAD = 5mA
LOAD = 10mA
LOAD = 100mA
LOAD = 200mA
LOAD = 300mA
5.05
VOUT = 3.3V
TA = 25°C
5.02
120
5.01
VOUT (V)
140
100
4.99
60
4.98
40
4.97
20
4.96
1000
ILOAD (mA)
3.60
3.70
4.95
09506-011
100
3.50
5.00
80
10
3.40
LOAD = 100µA
LOAD = 1mA
LOAD = 10mA
LOAD = 100mA
LOAD = 300mA
5.04
5.03
1
3.30
Figure 14. Ground Current vs. Input Voltage (in Dropout)
160
0
3.20
VIN (V)
Figure 11. Shutdown Current vs. Temperature at Various Input Voltages
DROPOUT (mV)
400
0
3.10
09506-010
0
–50
180
600
200
20
200
800
09506-013
120
1200
GROUND CURRENT (µA)
140
SHUTDOWN CURRENT (µA)
1400
3.3V
4.0V
6.0V
8.0V
12.0V
20.0V
–40°C
–5°C
25°C
85°C
125°C
TJ (°C)
Figure 12. Dropout Voltage vs. Load Current
09506-014
160
Data Sheet
Figure 15. Output Voltage vs. Junction Temperature, VOUT = 5 V
3.35
5.05
3.30
5.04
5.03
3.25
5.02
VOUT (V)
3.15
3.10
5.01
5.00
4.99
3.05
4.98
2.95
2.90
3.10
4.97
LOAD = 100µA
LOAD = 1mA
LOAD = 10mA
LOAD = 100mA
LOAD = 300mA
3.20
3.30
3.40
3.50
3.60
3.70
VIN (V)
4.96
4.95
0.1
1
10
100
1000
ILOAD (mA)
Figure 16. Output Voltage vs. Load Current, VOUT = 5 V
Figure 13. Output Voltage vs. Input Voltage (in Dropout)
Rev. A | Page 8 of 28
09506-015
3.00
09506-012
VOUT (V)
3.20
Data Sheet
900
LOAD = 100µA
LOAD = 1mA
LOAD = 10mA
LOAD = 100mA
LOAD = 300mA
5.04
700
GROUND CURRENT (µA)
5.03
5.01
5.00
4.99
4.98
600
500
400
300
4.97
200
4.96
100
8
10
12
14
16
18
20
VIN (V)
0
09506-016
6
6
16
18
20
VOUT = 5V
TA = 25°C
160
140
700
600
120
500
400
100
80
60
300
40
200
20
100
–5°C
25°C
85°C
125°C
TJ (°C)
1
09506-118
–40°C
10
100
09506-017
0
0
1000
ILOAD (mA)
Figure 18. Ground Current vs. Junction Temperature, VOUT = 5 V
Figure 21. Dropout Voltage vs. Load Current, VOUT = 5 V
700
5.05
600
5.00
4.95
500
4.90
VOUT (V)
400
300
4.85
4.80
200
4.75
100
LOAD = 5mA
LOAD = 10mA
LOAD = 100mA
LOAD = 200mA
LOAD = 300mA
4.70
0
0.1
1
10
100
ILOAD (mA)
1000
09506-119
GROUND CURRENT (µA)
14
180
DROPOUT (mV)
GROUND CURRENT (µA)
800
12
Figure 20. Ground Current vs. Input Voltage, VOUT = 5 V
LOAD = 100µA
LOAD = 1mA
LOAD = 10mA
LOAD = 100mA
LOAD = 300mA
900
10
VIN (V)
Figure 17. Output Voltage vs. Input Voltage, VOUT = 5 V
1000
8
4.65
4.8
4.9
5.0
5.1
VIN (V)
5.2
5.3
5.4
09506-018
VOUT (V)
5.02
4.95
LOAD = 100µA
LOAD = 1mA
LOAD = 10mA
LOAD = 100mA
LOAD = 300mA
800
09506-120
5.05
ADP7102
Figure 22. Output Voltage vs. Input Voltage (in Dropout), VOUT = 5 V
Figure 19. Ground Current vs. Load Current, VOUT = 5 V
Rev. A | Page 9 of 28
ADP7102
Data Sheet
1.85
2500
1.83
VOUT (V)
1500
1000
1.81
1.79
500
–500
4.80
1.77
LOAD = 5mA
LOAD = 10mA
LOAD = 100mA
LOAD = 200mA
LOAD = 300mA
4.90
5.00
1.75
5.10
5.20
5.30
5.40
VIN (V)
6
8
10
12
14
16
18
20
Figure 26. Output Voltage vs. Input Voltage, VOUT = 1.8 V
900
1.85
LOAD = 100µA
LOAD = 1mA
LOAD = 10mA
LOAD = 100mA
LOAD = 300mA
800
700
GROUND CURRENT (µA)
1.83
4
VIN (V)
Figure 23. Ground Current vs. Input Voltage (in Dropout), VOUT = 5 V
VOUT (V)
2
09506-022
0
09506-019
GROUND CURRENT (µA)
2000
LOAD = 100µA
LOAD = 1mA
LOAD = 10mA
LOAD = 100mA
LOAD = 300mA
1.81
1.79
LOAD = 100µA
LOAD = 1mA
LOAD = 10mA
LOAD = 100mA
LOAD = 300mA
600
500
400
300
200
1.77
0
–40°C
–5°C
25°C
85°C
–40°C
09506-020
1.75
125°C
TJ (°C)
–5°C
25°C
85°C
125°C
TJ (°C)
Figure 24. Output Voltage vs. Junction Temperature, VOUT = 1.8 V
Figure 27. Ground Current vs. Junction Temperature, VOUT = 1.8 V
1.85
700
09506-023
100
600
GROUND CURRENT (µA)
1.81
1.79
500
400
300
200
1.77
1.75
0.1
1
10
100
1000
ILOAD (mA)
Figure 25. Output Voltage vs. Load Current, VOUT = 1.8 V
0
0.1
1
10
100
1000
ILOAD (mA)
Figure 28. Ground Current vs. Load Current, VOUT = 1.8 V
Rev. A | Page 10 of 28
09506-128
100
09506-021
VOUT (V)
1.83
Data Sheet
5.08
1200
LOAD = 100µA
LOAD = 1mA
LOAD = 10mA
LOAD = 100mA
LOAD = 300mA
1000
GROUND CURRENT (µA)
ADP7102
LOAD = 100µA
LOAD = 1mA
LOAD = 10mA
LOAD = 100mA
LOAD = 300mA
5.07
5.06
5.05
VOUT (V)
800
600
5.04
5.03
5.02
400
5.01
5.00
200
2
4
6
8
10
12
14
16
18
20
VIN (V)
09506-129
4.98
0
5.06
LOAD = 100µA
LOAD = 1mA
LOAD = 10mA
LOAD = 100mA
LOAD = 300mA
2.0
5.05
VOUT (V)
10
12
14
16
18
20
Figure 32. Output Voltage vs. Input Voltage, VOUT = 5 V, Adjustable
IOUT SHUTDOWN CURRENT (µA)
5.07
8
VIN (V)
Figure 29. Ground Current vs. Input Voltage, VOUT = 1.8 V
5.08
6
09506-026
4.99
5.04
5.03
5.02
5.01
5.00
1.5
3.3V
4V
5V
6V
8V
10V
12V
15V
18V
20V
1.0
0.5
–5°C
25°C
85°C
125°C
TJ (°C)
0
5.07
–10
5.06
–20
5.05
–30
5.04
–40
5.02
5.01
20
40
60
80
100
120
140
LOAD = 300mA
LOAD = 100mA
LOAD = 10mA
LOAD = 1mA
–50
–60
–70
5.00
–80
4.99
–90
1
10
100
1000
ILOAD (mA)
09506-025
4.98
0.1
0
Figure 33. Reverse Input Current vs. Temperature, VIN = 0 V, Different
Voltages on VOUT
5.08
5.03
–20
TEMPERATURE (°C)
PSRR (dB)
VOUT (V)
Figure 30. Output Voltage vs. Junction Temperature, VOUT = 5 V, Adjustable
0
–40
09506-053
–40°C
–100
10
100
1k
10k
100k
1M
10M
FREQUENCY (Hz)
Figure 34. Power Supply Rejection Ratio vs. Frequency, VOUT = 1.8 V,
VIN = 3.3 V
Figure 31. Output Voltage vs. Load Current, VOUT = 5 V, Adjustable
Rev. A | Page 11 of 28
09506-027
4.98
09506-024
4.99
ADP7102
–30
–40
–40
–50
–60
–70
–80
–80
–90
–90
10
100
1k
10k
100k
1M
10M
Figure 35. Power Supply Rejection Ratio vs. Frequency, VOUT = 3.3 V,
VIN = 4.8 V
0
–10
–20
–100
10
0
LOAD = 300mA
LOAD = 100mA
LOAD = 10mA
LOAD = 1mA
–10
–40
PSRR (dB)
–40
–50
–60
–80
–80
–90
–90
–100
–100
10
100
1k
10k
100k
1M
10M
FREQUENCY (Hz)
Figure 36. Power Supply Rejection Ratio vs. Frequency, VOUT = 3.3 V,
VIN = 4.3 V
LOAD = 1mA
LOAD = 10mA
LOAD = 100mA
LOAD = 300mA
0
LOAD = 300mA
LOAD = 100mA
LOAD = 10mA
LOAD = 1mA
–10
1k
10k
100k
1M
10M
LOAD = 1mA
LOAD = 10mA
LOAD = 100mA
LOAD = 300mA
–20
–40
PSRR (dB)
–40
–50
–60
–50
–60
–70
–70
–80
–80
–90
–90
1k
10k
100k
1M
10M
FREQUENCY (Hz)
Figure 37. Power Supply Rejection Ratio vs. Frequency, VOUT = 3.3 V,
VIN = 3.8 V
–100
10
09506-030
100
100
Figure 39. Power Supply Rejection Ratio vs. Frequency, VOUT = 5 V, VIN = 6 V
–30
10
10M
FREQUENCY (Hz)
–30
–100
1M
–60
–70
–20
100k
–50
–70
0
10k
–20
–30
–10
1k
Figure 38. Power Supply Rejection Ratio vs. Frequency, VOUT = 5 V, VIN = 6.5 V
–30
10
100
FREQUENCY (Hz)
09506-029
PSRR (dB)
–60
–70
FREQUENCY (Hz)
PSRR (dB)
–50
09506-031
PSRR (dB)
–30
–100
LOAD = 1mA
LOAD = 10mA
LOAD = 100mA
LOAD = 300mA
–20
09506-028
PSRR (dB)
–20
–10
09506-032
–10
0
LOAD = 300mA
LOAD = 100mA
LOAD = 10mA
LOAD = 1mA
100
1k
10k
100k
FREQUENCY (Hz)
1M
10M
09506-033
0
Data Sheet
Figure 40. Power Supply Rejection Ratio vs. Frequency, VOUT = 5 V, VIN = 5.5 V
Rev. A | Page 12 of 28
Data Sheet
–20
–30
–30
–40
–40
–60
–60
–70
–70
–80
–80
–90
–90
–100
10
–100
10
100
1k
10k
100k
1M
10M
Figure 41. Power Supply Rejection Ratio vs. Frequency, VOUT = 5 V, VIN = 5.3 V
0
–10
0
–20
–30
–30
–40
–40
PSRR (dB)
–20
–80
–80
–90
–90
1k
10k
100k
1M
10M
FREQUENCY (Hz)
Figure 42. Power Supply Rejection Ratio vs. Frequency, VOUT = 5 V, VIN = 5.2 V
0
–10
–100
0
–30
–40
–40
PSRR (dB)
–20
–30
–70
–80
–90
–100
100k
1M
10M
09506-036
–90
–100
10
10k
Figure 43. Power Supply Rejection Ratio vs. Frequency, VOUT = 5 V, VIN = 6 V,
Adjustable
0.75
1.00
1.25
1.50
LOAD = 1mA
LOAD = 10mA
LOAD = 100mA
LOAD = 300mA
–60
–80
FREQUENCY (Hz)
0.50
–50
–70
1k
0.25
Figure 45. Power Supply Rejection Ratio vs. Headroom Voltage, 100 Hz,
VOUT = 5 V
–20
100
0
–10
–60
10M
HEADROOM VOLTAGE (V)
LOAD = 1mA
LOAD = 10mA
LOAD = 100mA
LOAD = 300mA
–50
1M
–60
–70
100
100k
–50
–70
–100
10
10k
LOAD = 1mA
LOAD = 10mA
LOAD = 100mA
LOAD = 300mA
–10
–60
1k
Figure 44. Power Supply Rejection Ratio vs. Frequency, VOUT = 5 V, VIN = 6 V,
Adjustable with Noise Reduction Circuit
LOAD = 1mA
LOAD = 10mA
LOAD = 100mA
LOAD = 300mA
–50
100
FREQUENCY (Hz)
09506-035
PSRR (dB)
–50
09506-038
–50
09506-037
PSRR (dB)
–20
FREQUENCY (Hz)
PSRR (dB)
LOAD = 1mA
LOAD = 10mA
LOAD = 100mA
LOAD = 300mA
–10
09506-034
PSRR (dB)
–10
0
LOAD = 1mA
LOAD = 10mA
LOAD = 100mA
LOAD = 300mA
0
0.25
0.50
0.75
1.00
HEADROOM VOLTAGE
1.25
1.50
09506-039
0
ADP7102
Figure 46. Power Supply Rejection Ratio vs. Headroom Voltage, 1 kHz,
VOUT = 5 V
Rev. A | Page 13 of 28
ADP7102
Data Sheet
0
10
LOAD = 1mA
LOAD = 10mA
LOAD = 100mA
LOAD = 300mA
–10
3.3V
5V
5V ADJ
5V ADJ NR
–20
1
–40
µV/√Hz
PSRR (dB)
–30
–50
–60
0.1
–70
–80
0.25
0.50
0.75
1.00
1.25
1.50
HEADROOM VOLTAGE (V)
0.01
10
09506-040
0
10k
100k
Figure 50. Output Noise Spectral Density, ILOAD = 10 mA, COUT = 1 μF
LOAD = 1mA
LOAD = 10mA
LOAD = 100mA
LOAD = 300mA
–10
1k
FREQUENCY (Hz)
Figure 47. Power Supply Rejection Ratio vs. Headroom Voltage, 10 kHz,
VOUT = 5 V
0
100
09506-043
–90
–100
LOAD CURRENT
–20
–30
PSRR (dB)
1
–40
–50
–60
2
OUTPUT VOLTAGE
–70
–80
0
0.25
0.50
0.75
1.00
1.25
1.50
HEADROOM VOLTAGE (V)
CH1 200mA Ω BW CH2 50mV
09506-041
–100
Figure 48. Power Supply Rejection Ratio vs. Headroom Voltage, 100 kHz,
VOUT = 5 V
B
W
M 20µs
T 10.4%
A CH1
76mA
09506-044
–90
Figure 51. Load Transient Response, CIN, COUT = 1 μF, ILOAD = 1 mA to 300 mA,
VOUT = 1.8 V, VIN = 5 V
30
LOAD CURRENT
25
20
15
2
OUTPUT VOLTAGE
3.3V
1.8V
5V
5VADJ
5VADJ NR
5
0
0.00001
0.0001
0.001
0.01
0.1
1
LOAD CURRENT (A)
Figure 49. Output Noise vs. Load Current and Output Voltage,
COUT = 1 μF
CH1 200mA Ω BW CH2 50mV
B
W
M 20µs
T 10.2%
A CH1
168mA
09506-045
10
09506-042
NOISE (µV rms)
1
Figure 52. Load Transient Response, CIN, COUT = 1 μF, ILOAD = 1 mA to 300 mA,
VOUT = 3.3 V, VIN = 5 V
Rev. A | Page 14 of 28
Data Sheet
ADP7102
INPUT VOLTAGE
LOAD CURRENT
1
OUTPUT VOLTAGE
2
OUTPUT VOLTAGE
2
B
W
M 20µs
T 10.2%
A CH1
216mA
CH1 1V
B
W
B
W
M 4µs
T 9.8%
A CH4
1.56V
Figure 55. Line Transient Response, CIN, COUT = 1 μF, ILOAD = 300 mA,
VOUT = 3.3 V
Figure 53. Load Transient Response, CIN, COUT = 1 μF, ILOAD = 1 mA to 300 mA,
VOUT = 5 V, VIN = 7 V
INPUT VOLTAGE
INPUT VOLTAGE
OUTPUT VOLTAGE
2
CH2 10mV
09506-048
CH1 200mA Ω BW CH2 50mV
09506-046
1
OUTPUT VOLTAGE
2
B
W
CH2 10mV
B
W
M 4µs
T 9.8%
A CH4
1.56V
1
09506-047
CH1 1V
Figure 54. Line Transient Response, CIN, COUT = 1 μF, ILOAD = 300 mA,
VOUT = 1.8 V
CH1 1V
B
W
CH2 10mV
B
W
M 4µs
T 9.8%
A CH4
1.56V
09506-049
1
Figure 56. Line Transient Response, CIN, COUT = 1 μF, ILOAD = 300 mA, VOUT = 5 V
Rev. A | Page 15 of 28
ADP7102
Data Sheet
INPUT VOLTAGE
INPUT VOLTAGE
OUTPUT VOLTAGE
2
OUTPUT VOLTAGE
2
B
W
CH2 10mV
B
W
M 4µs
T 9.8%
A CH4
1.56V
1
CH1 1V
Figure 57. Line Transient Response, CIN, COUT = 1 μF, ILOAD = 1 mA, VOUT = 1.8 V
OUTPUT VOLTAGE
B
W
CH2 10mV
B
W
M 4µs
T 9.8%
A CH4
1.56V
09506-051
1
CH1 1V
W
CH2 10mV
B
W
M 4µs
T 9.8%
A CH4
1.56V
Figure 59. Line Transient Response, CIN, COUT = 1 μF, ILOAD = 1 mA, VOUT = 5 V
INPUT VOLTAGE
2
B
09506-052
CH1 1V
09506-050
1
Figure 58. Line Transient Response, CIN, COUT = 1 μF, ILOAD = 1 mA, VOUT = 3.3 V
Rev. A | Page 16 of 28
Data Sheet
ADP7102
THEORY OF OPERATION
The ADP7102 is a low quiescent current, low-dropout linear
regulator that operates from 3.3 V to 20 V and provides up to
300 mA of output current. Drawing a low 750 μA of quiescent
current (typical) at full load makes the ADP7102 ideal for
battery-operated portable equipment. Typical shutdown
current consumption is 40 μA at room temperature.
Optimized for use with small 1 µF ceramic capacitors, the
ADP7102 provides excellent transient performance.
The ADP7102 is available in 7 fixed output voltage options,
ranging from 1.8 V to 9 V and in an adjustable version with
an output voltage that can be set to between 1.22 V and 19 V
by an external voltage divider. The output voltage can be set
according to the following equation:
VOUT = 1.22 V(1 + R1/R2)
VOUT
VREG
GND
SHORT-CIRCUIT,
THERMAL
PROTECT
PGOOD
VIN = 8V
PG
10µA
SHUTDOWN
VIN
R2
OFF
R3
ON 100kΩ
R4
100kΩ
EN/
UVLO
PGOOD
PG
SHUTDOWN
EN/
UVLO
SENSE
1.22V
REFERENCE
09506-056
10µA
SHORT-CIRCUIT,
THERMAL
PROTECT
PG
RPG
100kΩ
PG
The value of R2 should be less than 200 kΩ to minimize
errors in the output voltage caused by the ADJ pin input
current. For example, when R1 and R2 each equal 200 kΩ,
the output voltage is 2.44 V. The output voltage error
introduced by the ADJ pin input current is 2 mV or 0.08%,
assuming a typical ADJ pin input current of 10 nA at 25°C.
VOUT
GND
R2
13kΩ
VOUT = 5V
+ COUT
1µF
Figure 62. Typical Adjustable Output Voltage Application Schematic
Figure 60. Fixed Output Voltage Internal Block Diagram
VREG
R1
40.2kΩ
09506-055
GND
1.22V
REFERENCE
VIN
VOUT
ADJ
R1
SENSE
EN/
UVLO
CIN +
1µF
09506-057
VIN
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 61. Adjustable Output Voltage Internal Block Diagram
Internally, the ADP7102 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
The ADP7102 uses the EN/UVLO pin to enable and disable
the VOUT pin under normal operating conditions. When
EN/UVLO is high, VOUT turns on, when EN is low, VOUT
turns off. For automatic startup, EN/UVLO can be tied to VIN.
The ADP7102 incorporates reverse current protections
circuitry that prevents current flow backwards through the
pass element when the output voltage is greater than the input
voltage. A comparator senses the difference between the input
and output voltages. When the difference between the input
voltage and output voltage exceeds 55 mV, the body of the PFET
is switched to VOUT and turned off or opened. In other words,
the gate is connected to VOUT.
Rev. A | Page 17 of 28
ADP7102
Data Sheet
APPLICATIONS INFORMATION
Output Capacitor
The ADP7102 is designed for operation with small, spacesaving ceramic capacitors but functions with most commonly
used 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 1 µF capacitance with an ESR of 0.2 Ω or less is
recommended to ensure the stability of the ADP7102. 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 ADP7102 to large changes in load
current. Figure 63 shows the transient responses for an output
capacitance value of 1 µF.
Figure 64 depicts the capacitance vs. voltage bias characteristic
of an 0402, 1 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.
1.2
1.0
CAPACITANCE (µF)
CAPACITOR SELECTION
LOAD CURRENT
0.8
0.6
0.4
0
1
0
2
4
6
8
10
VOLTAGE (V)
Figure 64. Capacitance vs. Voltage Characteristic
OUTPUT VOLTAGE
2
09506-059
0.2
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)
09506-058
ΩB
Input Bypass Capacitor
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.
Connecting a 1 µF capacitor from VIN to GND reduces
the circuit sensitivity to printed circuit board (PCB) layout,
especially when long input traces or high source impedance
are encountered. If greater than 1 µF of output capacitance is
required, the input capacitor should be increased to match it.
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 0.94 μF at 1.8 V, as shown
in Figure 64.
Input and Output Capacitor Properties
Substituting these values in Equation 1 yields
CH1 200mA
W
CH2 50mV
B
W
M 20µs
T 10.4%
A CH1
76mA
Figure 63. Output Transient Response, VOUT = 1.8 V, COUT = 1 µF
Any good quality ceramic capacitors can be used with the
ADP7102, as long as they meet the minimum capacitance and
maximum ESR requirements. Ceramic capacitors are manufactured 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 50 V are
recommended. Y5V and Z5U dielectrics are not recommended,
due to their poor temperature and dc bias characteristics.
(1)
CEFF = 0.94 μF × (1 − 0.15) × (1 − 0.1) = 0.719 μF
Therefore, the capacitor chosen in this example meets the
minimum capacitance requirement of the LDO over temperature and tolerance at the chosen output voltage.
To guarantee the performance of the ADP7102, it is imperative
that the effects of dc bias, temperature, and tolerances on the
behavior of the capacitors be evaluated for each application.
Rev. A | Page 18 of 28
Data Sheet
ADP7102
PROGRAMABLE UNDERVOLTAGE LOCKOUT (UVLO)
2.0
1.8
1.6
VIN
VOUT
SENSE
OFF
R1
ON 100kΩ
R2
100kΩ
VOUT = 5V
+ COUT
1µF
RPG
100kΩ
EN/
UVLO
PG
PG
GND
Figure 66. Typical EN Pin Voltage Divider
Figure 65 shows the typical hysteresis of the EN/UVLO pin.
This prevents on/off oscillations that can occur due to noise
on the EN pin as it passes through the threshold points.
The ADP7102 uses an internal soft-start to limit the inrush
current when the output is enabled. The start-up time for the
3.3 V option is approximately 580 μs from the time the EN
active threshold is crossed to when the output reaches 90%
of its final value. As shown in Figure 67, the start-up time is
dependent on the output voltage setting.
1.4
1.2
VOUT, EN RISE
VOUT, EN FALL
1.0
CIN +
1µF
09506-061
The ADP7102 uses the EN/UVLO pin to enable and disable
the VOUT pin under normal operating conditions. As shown
in Figure 65, when a rising voltage on EN crosses the upper
threshold, VOUT turns on. When a falling voltage on EN/
UVLO crosses the lower threshold, VOUT turns off. The
hysteresis of the EN/UVLO threshold is determined by
the Thevenin equivalent resistance in series with the EN/
UVLO pin.
VIN = 8V
0.8
0.6
6
0.4
1.25
1.50
1.75
2.00
2.25
2.50
2.75
3.00
5V
5
Figure 65. Typical VOUT Response to EN Pin Operation
The upper and lower thresholds are user programmable and
can be set using two resistors. When the EN/UVLO pin voltage
is below 1.22 V, the LDO is disabled. When the EN/UVLO pin
voltage transitions above 1.22 V, the LDO is enabled and 10 µA
hysteresis current is sourced out of the pin raising the voltage,
thus providing threshold hysteresis. Typically, two external
resistors program the minimum operational voltage for the LDO.
The resistance values, R1 and R2 can be determined from:
VOUT (V)
4
3.3V
3
ENABLE
2
1
0
0
500
1000
1500
TIME (µs)
R1 = VHYS/10 μA
Figure 67. Typical Start-Up Behavior
R2 = 1.22 V × R1/(VIN − 1.22 V)
where:
VIN is the desired turn-on voltage.
VHYS is the desired EN/UVLO hysteresis level.
Hysteresis can also be achieved by connecting a resistor in series
with EN/UVLO pin. For the example shown in Figure 66, the
enable threshold is 2.44 V with a hysteresis of 1 V.
Rev. A | Page 19 of 28
2000
09506-062
0
1.00
09506-060
0.2
ADP7102
Data Sheet
POWER GOOD FEATURE
The ADP7102 provides a power good pin (PG) to indicate
the status of the output. This open-drain output requires an
external pull-up resistor to VIN. If the part is in shutdown
mode, current-limit mode, or thermal shutdown, or if it falls
below 90% of the nominal output voltage, the power-good pin
(PG) immediately transitions low. During soft-start, the rising
threshold of the power-good signal is 93.5% of the nominal
output voltage.
The open-drain output is held low when the ADP7102 has
sufficient input voltage to turn on the internal PG transistor.
The PG transistor is terminated via a pull-up resistor to VOUT
or VIN.
Power-good accuracy is 93.5% of the nominal regulator output
voltage when this voltage is rising, with a 90% trip point when
this voltage is falling. Regulator input voltage brownouts or
glitches trigger power no good signals if VOUT falls below 90%.
A normal power-down causes the power good signal to go low
when VOUT drops below 90%.
Figure 68 and Figure 69 show the typical power good rising and
falling threshold over temperature.
6
–40°C
–5°C
+25°C
+85°C
+125°C
The adjustable LDO circuit may be modified slightly to
reduce the output voltage noise to levels close to that of the
fixed output ADP7102. The circuit shown in Figure 70 adds
two additional components to the output voltage setting resistor
divider. CNR and RNR are added in parallel with RFB1 to reduce
the ac gain of the error amplifier. RNR is chosen to be equal to
RFB2; this limits the ac gain of the error amplifier to approximately 6 dB. The actual gain is the parallel combination of RNR
and RFB1, divided by RFB2. This ensures that the error amplifier
always operates at greater than unity gain.
CNR is chosen by setting the reactance of CNR equal to RFB1 −
RNR at a frequency between 50 Hz and 100 Hz. This sets the
frequency where the ac gain of the error amplifier is 3 dB
down from its dc gain.
VIN = 8V
4
PG (V)
The ultralow output noise of the fixed output ADP7102 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. The adjustable output ADP7102 uses the more
conventional architecture where the reference voltage is fixed
and the error amplifier gain is a function of the output voltage.
The disadvantage of the conventional LDO architecture is that
the output voltage noise is proportional to the output voltage.
CIN +
1µF
VIN
VOUT
RFB1
40.2kΩ
+ CNR
100nF
ADJ
3
ON
OFF
2
100kΩ
RFB2
13kΩ
EN/
UVLO
RNR
13kΩ
VOUT = 5V
+ COUT
1µF
100kΩ
100kΩ
GND
PG
PG
1
Figure 70. Noise Reduction Modification to Adjustable LDO
4.3
4.4
4.5
4.6
4.7
4.8
4.9
5.0
VOUT (V)
09506-063
0
4.2
Figure 68. Typical Power Good Threshold vs. Temperature, VOUT Rising
6
5
PG
PG
PG
PG
PG
–40°C
–5°C
+25°C
+85°C
+125°C
•
•
•
•
•
4
PG (V)
The noise of the LDO is approximately the noise of the fixed
output LDO (typically 15 µV rms) times the square root of the
parallel combination of RNR and RFB1 divided by RFB2. Based on
the component values shown in Figure 70, the ADP7102 has the
following characteristics:
3
2
•
0
4.2
4.3
4.4
4.5
4.6
VOUT (V)
4.7
4.8
4.9
5.0
09506-064
1
Figure 69. Typical Power Good Threshold vs. Temperature, VOUT Falling
Rev. A | Page 20 of 28
DC gain of 4.09 (12.2 dB)
3 dB roll off frequency of 59 Hz
High frequency ac gain of 1.82 (5.19 dB)
Noise reduction factor of 1.35 (2.59 dB)
RMS noise of the adjustable LDO without noise reduction
of 27.8 µV rms
RMS noise of the adjustable LDO with noise reduction (assuming 15 µV rms for fixed voltage option) of
20.25 µV rms
09506-065
5
PG
PG
PG
PG
PG
NOISE REDUCTION OF THE ADJUSTABLE
ADP7102
Data Sheet
ADP7102
CURRENT LIMIT AND THERMAL OVERLOAD
PROTECTION
The ADP7102 is protected against damage due to excessive
power dissipation by current and thermal overload protection
circuits. The ADP7102 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.
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 ADP7102 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.
Current and thermal limit protections are intended to protect
the device against accidental overload conditions. For reliable
operation, device power dissipation must be externally limited
so the junction temperature does not exceed 125°C.
THERMAL CONSIDERATIONS
In applications with low input-to-output voltage differential,
the ADP7102 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 that it causes 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 ADP7102 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 and 8-lead
LFCSP packages for various PCB copper sizes. Table 7 shows
the typical ΨJB values of the 8-lead SOIC and 8-lead LFCSP.
Table 6. Typical θJA Values
Copper Size (mm2)
251
100
500
1000
6400
1
LFCSP
165.1
125.8
68.1
56.4
42.1
θJA (°C/W)
SOIC
167.8
111
65.9
56.1
45.8
Device soldered to minimum size pin traces.
Table 7. Typical ΨJB Values
Model
LFCSP
SOIC
ΨJB (°C/W)
15.1
31.3
The junction temperature of the ADP7102 is calculated from
the following equation:
TJ = TA + (PD × θJA)
(2)
where:
TA is the ambient temperature.
PD is the power dissipation in the die, given by
PD = [(VIN − VOUT) × ILOAD] + (VIN × IGND)
(3)
where:
ILOAD is the load current.
IGND is the ground current.
VIN and VOUT are input and output voltages, respectively.
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}
(4)
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 71 to Figure 78 show junction temperature
calculations for different ambient temperatures, power dissipation, and areas of PCB copper.
Rev. A | Page 21 of 28
Data Sheet
145
135
135
125
125
115
105
95
85
75
65
55
35
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)
85
75
65
55
6400mm 2
500mm 2
25mm 2
TJ MAX
35
25
0
0.2
0.4
0.6
130
130
JUNCTION TEMPERATURE (°C)
140
120
110
100
90
80
70
6400mm 2
500mm 2
25mm 2
TJ MAX
60
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
TOTAL POWER DISSIPATION (W)
70
6400mm 2
500mm 2
25mm 2
TJ MAX
50
0
0.2
0.4
JUNCTION TEMPERATURE (°C)
105
95
85
6400mm 2
500mm 2
25mm 2
TJ MAX
75
0.6
0.7
TOTAL POWER DISSIPATION (W)
0.6
0.8
1.0
1.2
1.4
1.6
1.8
TOTAL POWER DISSIPATION (W)
0.8
0.9
125
115
105
95
85
6400mm 2
500mm 2
25mm 2
TJ MAX
75
1.0
09506-068
JUNCTION TEMPERATURE (°C)
115
0.5
2.4
Figure 75. SOIC, TA = 50°C
125
0.4
2.2
80
135
0.3
2.0
90
135
0.2
1.8
110
145
0.1
1.6
100
145
0
1.4
120
Figure 72. LFCSP, TA = 50°C
65
1.2
60
09506-067
JUNCTION TEMPERATURE (°C)
140
0
1.0
Figure 74. SOIC, TA = 25°C
Figure 71. LFCSP, TA = 25°C
50
0.8
TOTAL POWER DISSIPATION (W)
09506-070
0
95
65
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
TOTAL POWER DISSIPATION (W)
Figure 76. SOIC, TA = 85°C
Figure 73. LFCSP, TA = 85°C
Rev. A | Page 22 of 28
0.8
0.9
1.0
09506-071
25
105
45
6400mm 2
500mm 2
25mm 2
TJ MAX
45
115
09506-069
JUNCTION TEMPERATURE (°C)
145
09506-066
JUNCTION TEMPERATURE (°C)
ADP7102
Data Sheet
ADP7102
140
In the case where the board temperature is known, use the
thermal characterization parameter, ΨJB, to estimate the
junction temperature rise (see Figure 77 and Figure 78).
Maximum junction temperature (TJ) is calculated from
the board temperature (TB) and power dissipation (PD)
using the following formula:
(5)
80
60
40
140
20
120
0
TB = 25°C
TB = 50°C
TB = 65°C
TB = 85°C
TJ MAX
0
0.5
1.0
1.5
2.0
2.5
TOTAL POWER DISSIPATION (W)
100
Figure 78. SOIC
80
60
40
TB = 25°C
TB = 50°C
TB = 65°C
TB = 85°C
TJ MAX
20
0
0
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0
TOTAL POWER DISSIPATION (W)
09506-072
JUNCTION TEMPERATURE (TJ)
The typical value of ΨJB is 15.1°C/W for the 8-lead LFCSP
package and 31.3°C/W for the 8-lead SOIC package.
100
Figure 77. LFCSP
Rev. A | Page 23 of 28
3.0
3.5
09506-073
TJ = TB + (PD × ΨJB)
JUNCTION TEMPERATURE (TJ)
120
ADP7102
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
ADP7102. 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.
09506-075
Place the input capacitor as close as possible to the VIN and
GND pins. Place the output capacitor as close as possible to the
VOUT and GND pins. Use of 0805 or 0603 size capacitors and
resistors achieves the smallest possible footprint solution on
boards where area is limited.
09506-074
Figure 80. Example SOIC PCB Layout
Figure 79. Example LFCSP PCB Layout
Rev. A | Page 24 of 28
Data Sheet
ADP7102
OUTLINE DIMENSIONS
2.48
2.38
2.23
3.00
BSC SQ
8
5
EXPOSED
PAD
INDEX
AREA
4
1
0.80 MAX
0.55 NOM
SEATING
PLANE
0.30
0.25
0.18
PIN 1
INDICATOR
(R 0.2)
BOTTOM VIEW
TOP VIEW
0.80
0.75
0.70
1.74
1.64
1.49
0.05 MAX
0.02 NOM
COPLANARITY
0.08
0.20 REF
0.50 BSC
FOR PROPER CONNECTION OF
THE EXPOSED PAD, REFER TO
THE PIN CONFIGURATION AND
FUNCTION DESCRIPTIONS
SECTION OF THIS DATA SHEET.
112008-A
0.50
0.40
0.30
COMPLIANT TO JEDEC STANDARDS MO-229-WEED-4
Figure 81. 8-Lead Lead Frame Chip Scale Package [LFCSP_WD]
3 mm × 3 mm Body, Very Very Thin, Dual Lead
(CP-8-5)
Dimensions shown in millimeters
5.00
4.90
4.80
3.098
0.356
6.20
6.00
5.80
5
4.00
3.90
3.80
2.41
0.457
4
1
FOR PROPER CONNECTION OF
THE EXPOSED PAD, REFER TO
THE PIN CONFIGURATION AND
FUNCTION DESCRIPTIONS
SECTION OF THIS DATA SHEET.
BOTTOM VIEW
1.27 BSC
3.81 REF
TOP VIEW
1.65
1.25
1.75
1.35
SEATING
PLANE
0.51
0.31
0.50
0.25
0.10 MAX
0.05 NOM
COPLANARITY
0.10
8°
0°
45°
0.25
0.17
1.04 REF
1.27
0.40
COMPLIANT TO JEDEC STANDARDS MS-012-A A
Figure 82. 8-Lead Standard Small Outline Package, with Exposed Pad [SOIC_N_EP]
Narrow Body
(RD-8-2)
Dimensions shown in millimeters
Rev. A | Page 25 of 28
06-03-2011-B
8
ADP7102
Data Sheet
ORDERING GUIDE
Model 1
ADP7102ACPZ-R7
ADP7102ACPZ-1.5-R7
ADP7102ACPZ-1.8-R7
ADP7102ACPZ-2.5-R7
ADP7102ACPZ-3.0-R7
ADP7102ACPZ-3.3-R7
ADP7102ACPZ-5.0-R7
ADP7102ACPZ-9.0-R7
ADP7102ARDZ-R7
ADP7102ARDZ-1.5-R7
ADP7102ARDZ-1.8-R7
ADP7102ARDZ-2.5-R7
ADP7102ARDZ-3.0-R7
ADP7102ARDZ-3.3-R7
ADP7102ARDZ-5.0-R7
ADP7102ARDZ-9.0-R7
ADP7102CP-EVALZ
ADP7102RD-EVALZ
ADP7102CPZ-REDYKIT
ADP7102RDZ-REDYKIT
Temperature
Range
−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
Output
Voltage (V) 2, 3
Adjustable
1.5
1.8
2.5
3.0
3.3
5
9
Adjustable
1.5
1.8
2.5
3.0
3.3
5
9
3.3
3.3
Package
Description
LFCSP_WD
LFCSP_WD
LFCSP_WD
LFCSP_WD
LFCSP_WD
LFCSP_WD
LFCSP_WD
LFCSP_WD
SOIC_N_EP
SOIC_N_EP
SOIC_N_EP
SOIC_N_EP
SOIC_N_EP
SOIC_N_EP
SOIC_N_EP
SOIC_N_EP
LFCSP Evaluation Board
SOIC Evaluation Board
LFCSP REDYKIT
SOIC REDYKIT
Z = RoHS Compliant Part.
For additional voltage options, contact a local Analog Devices, Inc., sales or distribution representative.
3
The ADP7102CP-EVALZ and ADP7102RD-EVALZ evaluation boards are preconfigured with a 3.3 V ADP7102.
1
2
Rev. A | Page 26 of 28
Package
Option
CP-8-5
CP-8-5
CP-8-5
CP-8-5
CP-8-5
CP-8-5
CP-8-5
CP-8-5
RD-8-2
RD-8-2
RD-8-2
RD-8-2
RD-8-2
RD-8-2
RD-8-2
RD-8-2
Branding
LHO
LJV
LJW
LJZ
LKO
LK1
LK2
LLC
Data Sheet
ADP7102
NOTES
Rev. A | Page 27 of 28
ADP7102
Data Sheet
NOTES
©2011 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D09506-0-11/11(A)
Rev. A | Page 28 of 28