ANACHIP ADP7182

–28 V, −200 mA, Low Noise, Linear
Regulator
ADP7182
Data Sheet
FEATURES
TYPICAL APPLICATION CIRCUITS
GND
VIN = –8V
ON
OFF
–2V
VIN
VOUT = –5V
VOUT
ADP7182
2V
EN
0V
NC
ON
Figure 1. ADP7182 with Fixed Output Voltage, VOUT = −5 V
CIN
2.2µF
COUT
2.2µF
GND
ON
OFF
VIN
2V
0V
VOUT
13kΩ
40.2kΩ
VOUT = –5V
ADP7182
EN
ADJ
ON
10703-002
VIN = –8V
–2V
APPLICATIONS
COUT
2.2µF
CIN
2.2µF
10703-001
Low noise: 18 µV rms
Power supply rejection ratio (PSRR): 66 dB at 10 kHz at VOUT = −3 V
Positive or negative enable logic
Stable with small 2.2 µF ceramic output capacitor
Input voltage range: −2.7 V to −28 V
Maximum output current: −200 mA
Low dropout voltage: −185 mV at −200 mA load
Initial accuracy: ±1%
Accuracy over line, load, and temperature
+2% maximum/−3% minimum
Low quiescent current, IGND = −650 µA with −200 mA load
Low shutdown current: −2 µA
Adjustable output from −1.22 V to −VIN + VDO
Current-limit and thermal overload protection
8-lead LFCSP and 5-lead TSOT
Figure 2. ADP7182 with Adjustable Output Voltage, VOUT = −5 V
Regulation to noise sensitive applications
Analog-to-digital converter (ADC) and digital-to-analog
converter (DAC) circuits, precision amplifiers
Communications and infrastructure
Medical and healthcare
Industrial and instrumentation
GENERAL DESCRIPTION
The ADP7182 is a CMOS, low dropout (LDO) linear regulator
that operates from −2.7 V to −28 V and provides up to −200 mA
of output current. This high input voltage LDO is ideal for
regulation of high performance analog and mixed signal circuits
operating from −27 V down to −1.22 V rails. Using an advanced
proprietary architecture, it provides high power supply rejection
and low noise, and achieves excellent line and load transient
response with a small 2.2 µF ceramic output capacitor.
Rev. A
The ADP7182 is available in a fixed output voltage and an
adjustable version that allows the output voltage to range from
−1.22 V to −VIN + VDO via an external feedback divider.
The ADP7182 regulator output noise is 18 µV rms independent
of the output voltage. The enable logic is capable of interfacing
with positive or negative logic levels for maximum flexibility.
The ADP7182 is available in an 8-lead LFCSP package for a
small, low profile footprint. The 5-lead TSOT package is
scheduled for release by the end of 2013.
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ADP7182
Data Sheet
TABLE OF CONTENTS
Features .............................................................................................. 1
Theory of Operation ...................................................................... 20
Applications ....................................................................................... 1
Enable Pin Operation ................................................................ 20
Typical Application Circuits............................................................ 1
Adjustable Mode Operation ..................................................... 20
General Description ......................................................................... 1
Applications Information .............................................................. 21
Revision History ............................................................................... 2
ADIsimPower Design Tool ....................................................... 21
Specifications..................................................................................... 3
Capacitor Selection .................................................................... 21
Input and Output Capacitance, Recommended
Specifications ................................................................................ 4
Enable Pin Operation ................................................................ 22
Absolute Maximum Ratings ............................................................ 5
Noise Reduction of the Adjustable ADP7182 ............................ 23
Thermal Data ................................................................................ 5
Current-Limit and Thermal Overload Protection ................. 23
Thermal Resistance ...................................................................... 5
Thermal Considerations............................................................ 24
ESD Caution .................................................................................. 5
PCB Layout Considerations ...................................................... 26
Pin Configurations and Function Descriptions ........................... 6
Outline Dimensions ....................................................................... 27
Typical Performance Characteristics ............................................. 8
Ordering Guide .......................................................................... 27
Soft Start ...................................................................................... 22
REVISION HISTORY
5/13—Rev. 0 to Rev. A
Changed Start-Up Time VOUT = −5 V from 450 µs to 550 µs ..... 3
Changes to Figure 9 and Figure 12 ................................................. 8
Changes to Figure 13 ........................................................................ 9
Changes to Figure 19 and Figure 22............................................. 10
Changes to Figure 28 ...................................................................... 11
Changes to Figure 31 and Figure 34............................................. 12
Changes to Figure 37 and Figure 40............................................. 13
Changes to Figure 43 ...................................................................... 14
Added ADIsimPower Design Tool Section ................................. 21
4/13—Revision 0: Initial Version
Rev. A | Page 2 of 28
Data Sheet
ADP7182
SPECIFICATIONS
VIN = (VOUT − 0.5 V) or −2.7 V (whichever is greater), EN = VIN, IOUT = −10 mA, CIN = COUT = 2.2 µF, TJ = −40°C to +125°C for
minimum/maximum specifications, TA = 25°C for typical specifications, unless otherwise noted.
Table 1.
Parameter
INPUT VOLTAGE RANGE
OPERATING SUPPLY CURRENT
Symbol
VIN
IGND
SHUTDOWN CURRENT
IGND-SD
OUTPUT VOLTAGE ACCURACY
Fixed Output Voltage Accuracy
Adjustable Output Voltage
Accuracy
VOUT
VADJ
LINE REGULATION
LOAD REGULATION 1
ADJ INPUT BIAS CURRENT
DROPOUT VOLTAGE 2
∆VOUT/∆VIN
∆VOUT/∆IOUT
ADJI-BIAS
VDO
START-UP TIME 3
tSTART-UP
CURRENT-LIMIT THRESHOLD 4
THERMAL SHUTDOWN
Thermal Shutdown Threshold
Thermal Shutdown Hysteresis
EN THRESHOLD
Positive Rise
Negative Rise
Positive Fall
Negative Fall
INPUT VOLTAGE LOCKOUT
Start Threshold
Shutdown Threshold
Hysteresis
OUTPUT NOISE
ILIMIT
Test Conditions/Comments
IOUT = 0 µA
IOUT = −10 mA
IOUT = −200 mA
EN = GND
EN = GND, VIN = −2.7 V to −28 V
–1
–3
−1.208
−1 mA < IOUT < −200 mA, VIN = (VOUT − 0.5 V) to −28 V
VIN = (VOUT − 0.5 V) to −28 V
IOUT = −1 mA to −200 mA
−1 mA < IOUT < −200 mA, VIN = (VOUT − 0.5 V) to −28 V
IOUT = −10 mA
IOUT = −50 mA
IOUT = −200 mA
VOUT = −5 V
VOUT = −2.8 V
−1.184
−0.01
−230
TJ rising
VEN-POS-RISE
VEN-NEG-RISE
VEN-POS-FALL
VEN-NEG-FALL
VOUT = off to on (positive)
VOUT = off to on (negative)
VOUT = on to off (positive)
VOUT = on to off (negative)
Typ
−33
−100
−650
−2
IOUT = −10 mA, TA = 25°C
−1 mA < IOUT < −200 mA, VIN = (VOUT − 0.5 V) to −28 V
IOUT = −10 mA
TSSD
TSSD-HYS
−1.22
0.001
10
−25
−46
−185
550
375
−350
Max
−28
−53
−150
−850
−8
Unit
V
µA
µA
µA
µA
µA
+1
+2
−1.232
%
%
V
−1.244
+0.01
0.006
V
%/V
%/mA
nA
mV
mV
mV
µs
µs
mA
−70
−90
−360
−500
150
15
VSTART
VSHUTDOWN
OUTNOISE
Min
−2.7
1.2
−2.0
0.3
−0.55
−2.695
10 Hz to 100 kHz, VOUT = −1.5 V, VOUT = −3 V, and
VOUT = −5 V
10 Hz to 100 kHz, VOUT = −5 V, adjustable mode,
CNR = open, RNR = open, RFB1 = 147 kΩ, RFB2 = 13 kΩ
10 Hz to 100 kHz, VOUT = −5 V, adjustable mode,
CNR = 100 nF, RNR = 13 kΩ, RFB1 = 147 kΩ, RFB2 = 13 kΩ
Rev. A | Page 3 of 28
°C
°C
−2.49
−2.34
150
18
−2.1
V
V
V
V
V
V
mV
µV rms
150
µV rms
33
µV rms
ADP7182
Parameter
POWER SUPPLY REJECTION RATIO
Data Sheet
Symbol
PSRR
Test Conditions/Comments
1 MHz, VIN = −4.3 V, VOUT = −3 V
1 MHz, VIN = −6 V, VOUT = −5 V
100 kHz, VIN = −4.3 V, VOUT = −3 V
100 kHz, VIN = −6 V, VOUT = −5 V
10 kHz, VIN = −4.3 V, VOUT = −3 V
10 kHz, VIN = −6 V, VOUT = −5 V
1 MHz, VIN = −16 V, VOUT = −15 V, adjustable mode,
CNR = 100 nF, RNR = 13 kΩ, RFB1 = 13 kΩ, RFB2 = 147 kΩ
100 kHz, VIN = −16 V, VOUT = −15 V, adjustable mode,
CNR = 100 nF, RNR = 13 kΩ, RFB1 = 13 kΩ, RFB2 = 147 kΩ
10 kHz, VIN = −16 V, VOUT = −15 V, adjustable mode,
CNR = 100 nF, RNR = 13 kΩ, RFB1 = 13 kΩ, RFB2 = 147 kΩ
Min
Typ
45
32
45
45
66
66
45
Max
Unit
dB
dB
dB
dB
dB
dB
dB
45
dB
66
dB
Based on an endpoint calculation using −1 mA and −200 mA loads. See Figure 8 for the 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 below −3 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 V
output voltage is defined as the current that causes the output voltage to drop to 90% of −5 V, or −4.5 V.
1
2
INPUT AND OUTPUT CAPACITANCE, RECOMMENDED SPECIFICATIONS
Table 2.
Parameter
INPUT AND OUTPUT CAPACITANCE
Minimum Capacitance 1
Capacitor Effective Series Resistance (ESR)
1
Symbol
Test Conditions/Comments
Min
Typ
CMIN
RESR
TA = −40°C to +125°C
TA = −40°C to +125°C
1.5
0.001
2.2
Max
Unit
0.2
µF
Ω
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;
Y5V and Z5U capacitors are not recommended for use with any LDO.
Rev. A | Page 4 of 28
Data Sheet
ADP7182
ABSOLUTE MAXIMUM RATINGS
Table 3.
Parameter
VIN to GND
VOUT to GND
EN to GND
EN to VIN
ADJ to GND
Storage Temperature Range
Operating Junction Temperature Range
Operating Ambient Temperature Range
Soldering Conditions
Rating
+0.3 V to −30 V
0.3 V to VIN
5 V to VIN
+30 V to −0.3 V
+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; 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.
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.
ΨJB is the junction-to-board thermal characterization parameter
with units of °C/W. 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 junction temperature is
calculated from the board temperature (TB) and power dissipation
using the formula
THERMAL DATA
TJ = TB + (PD × ΨJB)
Absolute maximum ratings apply individually only, not in
combination. The ADP7182 can be damaged when the junction
temperature limits are exceeded. Monitoring ambient temperature
does not guarantee that junction temperature (TJ) is within the
specified temperature limits. In applications with high power
dissipation and poor thermal resistance, the maximum ambient
temperature may have to be derated.
In applications with moderate power dissipation and low printed
circuit board (PCB) thermal resistance, the maximum ambient
temperature can exceed the maximum limit as long as the junction
temperature is within specification limits. The TJ of the device is
dependent on the ambient temperature (TA), the power dissipation
of the device (PD), and the junction-to-ambient thermal resistance
of the package (θJA).
See JESD51-8 and JESD51-12 for more detailed information
about ΨJB.
THERMAL RESISTANCE
θJA, θJC, and ΨJB are specified for the worst-case conditions, that is, a
device soldered in a circuit board for surface-mount packages.
Table 4. Thermal Resistance
Package Type
8-Lead LFCSP
5-Lead TSOT
ESD CAUTION
Maximum TJ is calculated from the TA and PD using the formula
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
50.2
170
θJC
31.7
Not applicable
ΨJB
18.2
43
Unit
°C/W
°C/W
ADP7182
Data Sheet
PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS
5
VOUT
GND
1
VIN 2
TOP VIEW
(Not to Scale)
EN 3
VOUT
4
EN 3
NC
4
ADJ
NOTES
1. NC = NO CONNECT. DO NOT
CONNECT TO THIS PIN.
TOP VIEW
(Not to Scale)
10703-003
VIN 2
5
ADP7182
ADP7182
10703-004
GND 1
Figure 3. 5-Lead TSOT Pin Configuration, Fixed Output Voltage
Figure 4. 5-Lead TSOT Pin Configuration, Adjustable Output Voltage
Table 5. 5-Lead TSOT Pin Function Descriptions
TSOT Pin No.
Fixed Output Voltage Adjustable Output Voltage
1
1
2
2
Mnemonic
GND
VIN
3
3
EN
4
Not applicable
5
Not applicable
4
5
NC
ADJ
VOUT
Description
Ground.
Regulator Input Supply. Bypass VIN to GND with a 2.2 µF or greater
capacitor.
Drive EN 2 V above or below ground to enable the regulator, or
drive EN to ground to turn off the regulator. For automatic startup,
connect EN to VIN.
No Connect. Do not connect to this pin.
Adjustable Input. An external resistor divider sets the output voltage.
Regulated Output Voltage. Bypass VOUT to GND with a 2.2 µF or
greater capacitor.
Rev. A | Page 6 of 28
Data Sheet
ADP7182
NC 3
TOP VIEW
(Not to Scale)
EXPOSED PAD
EN 4
VOUT 1
7 VIN
VOUT 2
ADJ 3
6 GND
5 NC
EN 4
NOTES
1. NC = NO CONNECT. DO NOT CONNECT TO THIS PIN.
2. THE EXPOSED PAD ON THE BOTTOM OF THE LFCSP PACKAGE ENHANCES
THERMAL PERFORMANCE AND IS ELECTRICALLY CONNECTED TO VIN
INSIDE THE PACKAGE. THE EXPOSED PAD MUST BE CONNECTED TO THE
VIN PLANE ON THE BOARD FOR PROPER OPERATION. BECAUSE THIS IS A
NEGATIVE VOLTAGE REGULATOR, VIN IS THE MOST NEGATIVE POTENTIAL
IN THE CIRCUIT.
8 VIN
ADP7182
7 VIN
TOP VIEW
(Not to Scale)
6 GND
EXPOSED PAD
5 NC
NOTES
1. NC = NO CONNECT. DO NOT CONNECT TO THIS PIN.
2. THE EXPOSED PAD ON THE BOTTOM OF THE LFCSP PACKAGE ENHANCES
THERMAL PERFORMANCE AND IS ELECTRICALLY CONNECTED TO VIN
INSIDE THE PACKAGE. THE EXPOSED PAD MUST BE CONNECTED TO THE
VIN PLANE ON THE BOARD FOR PROPER OPERATION. BECAUSE THIS IS A
NEGATIVE VOLTAGE REGULATOR, VIN IS THE MOST NEGATIVE POTENTIAL
IN THE CIRCUIT.
10703-006
ADP7182
VOUT 2
8 VIN
10703-005
VOUT 1
Figure 6. 8-Lead LFCSP Pin Configuration, Adjustable Output Voltage
Figure 5. 8-Lead LFCSP Pin Configuration, Fixed Output Voltage
Table 6. 8-Lead LFCSP Pin Function Descriptions
LFCSP Pin No.
Fixed Output Voltage Adjustable Output Voltage
1, 2
1, 2
Mnemonic
VOUT
Not applicable
3
4
3
Not applicable
4
ADJ
NC
EN
5
6
7, 8
5
6
7, 8
NC
GND
VIN
9
9
EPAD
Description
Regulated Output Voltage. Bypass VOUT to GND with a 2.2 µF or
greater capacitor.
Adjustable Input. An external resistor divider sets the output voltage.
No Connect. Do not connect to this pin.
Drive EN 2 V above or below ground to enable the regulator, or
drive EN to ground to turn off the regulator. For automatic startup,
connect EN to VIN.
No Connect. Do not connect to this pin.
Ground.
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 LFCSP package
enhances thermal performance and is electrically connected to VIN
inside the package. The exposed pad must be connected to the VIN
plane on the board for proper operation. Because this is a negative
voltage regulator, VIN is the most negative potential in the circuit.
Rev. A | Page 7 of 28
ADP7182
Data Sheet
TYPICAL PERFORMANCE CHARACTERISTICS
VIN = −3.5 V, VOUT = −3 V, IOUT = −10 mA, CIN = COUT = 2.2 µF, TA = 25°C, unless otherwise noted.
–2.980
VOUT (V)
–2.985
0
= –100µA
= –1mA
= –10mA
= –50mA
= –100mA
= –200mA
–100
–2.990
–2.995
–3.000
–3.005
–200
–300
–400
ILOAD
ILOAD
ILOAD
ILOAD
ILOAD
ILOAD
–500
–600
–3.010
= –100µA
= –1mA
= –10mA
= –50mA
= –100mA
= –200mA
–700
–3.015
–40
–5
25
85
–800
10703-007
–3.020
125
JUNCTION TEMPERATURE (°C)
–40
–5
25
85
10703-010
–2.975
ILOAD
ILOAD
ILOAD
ILOAD
ILOAD
ILOAD
GROUND CURRENT (µA)
–2.970
125
JUNCTION TEMPERATURE (°C)
Figure 10. Ground Current vs. Junction Temperature (TJ)
Figure 7. Output Voltage (VOUT) vs. Junction Temperature (TJ)
0
–2.95
–2.96
–100
GROUND CURRENT (µA)
–2.97
VOUT (V)
–2.98
–2.99
–3.00
–3.01
–3.02
–200
–300
–400
–500
–600
–3.03
–150
–100
50
0
–50
ILOAD (mA)
–800
–250
10703-008
–3.05
–200
–150
–100
–50
0
50
ILOAD (mA)
Figure 11. Ground Current vs. Load Current (ILOAD)
Figure 8. Output Voltage (VOUT) vs. Load Current (ILOAD)
0
–2.90
= –100µA
= –1mA
= –10mA
= –50mA
= –100mA
= –200mA
–100
–3.00
–3.05
–200
–300
–400
–500
–600
–3.10
–30
–25
–20
–15
–10
–5
VIN (V)
0
10703-009
–700
–800
–30
ILOAD = –100µA
ILOAD = –1mA
ILOAD = –10mA
–25
–20
ILOAD = –50mA
ILOAD = –100mA
ILOAD = –200mA
–15
–10
–5
VIN (V)
Figure 12. Ground Current vs. Input Voltage (VIN)
Figure 9. Output Voltage (VOUT) vs. Input Voltage (VIN)
Rev. A | Page 8 of 28
0
10703-012
GROUND CURRENT (µA)
ILOAD
ILOAD
ILOAD
ILOAD
ILOAD
ILOAD
–2.95
VOUT (V)
–200
10703-011
–700
–3.04
Data Sheet
ADP7182
0
0
–0.5
–200
GROUND CURRENT (µA)
–2.0
–2.5
–3.0
–3.5
–4.0
–4.5
–5.0
–50
VIN = –2.7V
VIN = –3.0V
VIN = –4.0V
VIN = –5.0V
VIN = –8.0V
VIN = –28.0V
–25
–400
–600
–800
–1000
0
25
50
75
100
125
–1200
–3.4
TEMPERATURE (°C)
–3.2
–3.0
–2.8
Figure 16. Ground Current vs. Input Voltage (VIN) in Dropout
0
–4.90
–4.92
–40
–4.94
–60
–4.96
–80
–4.98
–100
–120
–5.00
–5.02
–140
–5.04
–160
–5.06
–180
–5.08
–200
1
10
100
1000
ILOAD (mA)
–5.10
125
–5.000
ILOAD
ILOAD
ILOAD
ILOAD
ILOAD
ILOAD
= –5mA
= –10mA
= –25mA
= –50mA
= –100mA
= –200mA
–5.005
–5.010
–5.015
VOUT (V)
–2.75
–2.80
–5.020
–5.025
–5.030
–2.90
–5.035
–2.95
–5.040
–3.00
–5.045
–3.2
–3.0
–2.8
VIN (V)
10703-015
–2.85
–3.05
–3.4
85
–5.050
–200
–150
–100
–50
0
ILOAD (mA)
Figure 18. Output Voltage (VOUT) vs. Load Current (ILOAD), VOUT = −5 V
Figure 15. Output Voltage (VOUT) vs. Input Voltage (VIN) in Dropout
Rev. A | Page 9 of 28
10703-018
–2.70
25
JUNCTION TEMPERATURE (°C)
–2.55
–2.65
–5
–40
= –100µA
= –1mA
= –10mA
= –50mA
= –100mA
= –200mA
Figure 17. Output Voltage (VOUT) vs. Junction Temperature (TJ), VOUT = −5 V
Figure 14. Dropout Voltage vs. Load Current (ILOAD)
–2.60
ILOAD
ILOAD
ILOAD
ILOAD
ILOAD
ILOAD
10703-017
VOUT (V)
–20
10703-014
DROPOUT VOLTAGE (mV)
ILOAD = –50mA
ILOAD = –100mA
ILOAD = –200mA
VIN (V)
Figure 13. Shutdown Current vs. Temperature at Various Input Voltages
VOUT (V)
ILOAD = –5mA
ILOAD = –10mA
ILOAD = –25mA
10703-016
–1.5
10703-013
SHUTDOWN CURRENT (µA)
–1.0
ADP7182
Data Sheet
0
–4.97
–100
–5.01
–300
–400
–500
–600
–5.02
–700
–25
–20
–15
–10
–5
–800
–30
10703-019
–5.03
–30
0
VIN (V)
–100
–20
–200
–40
DROPOUT VOLTAGE (mV)
–300
–400
ILOAD = –50mA
ILOAD = –100mA
ILOAD = –200mA
–10
–5
0
–60
–80
–100
–120
–140
–700
–40
–5
25
85
–160
10703-020
–800
125
JUNCTION TEMPERATURE (°C)
1
10
100
1000
ILOAD (mA)
Figure 20. Ground Current vs. Junction Temperature (TJ), VOUT = −5 V
Figure 23. Dropout Voltage vs. Load Current (ILOAD), VOUT = −5 V
0
–4.60
–100
–4.65
–4.70
–200
ILOAD
ILOAD
ILOAD
ILOAD
ILOAD
ILOAD
= –5mA
= –10mA
= –25mA
= –50mA
= –100mA
= –200mA
–4.75
VOUT (V)
–300
–400
–4.80
–4.85
–500
–4.90
–600
–4.95
–700
–800
–200
–5.00
–150
–100
–50
ILOAD (mA)
Figure 21. Ground Current vs. Load Current (ILOAD), VOUT = −5 V
0
–5.05
–5.4
10703-021
GROUND CURRENT (µA)
–15
10703-023
GROUND CURRENT (µA)
0
–600
–20
Figure 22. Ground Current vs. Input Voltage (VIN), VOUT = −5 V
0
ILOAD = –100µA
ILOAD = –1mA
ILOAD = –10mA
–25
ILOAD = –50mA
ILOAD = –100mA
ILOAD = –200mA
VIN (V)
Figure 19. Output Voltage vs. Input Voltage (VIN), VOUT = −5 V
–500
ILOAD = –100µA
ILOAD = –1mA
ILOAD = –10mA
10703-022
–5.00
–200
–5.2
–5.0
VIN (V)
–4.8
10703-024
VOUT (V)
–4.99
= –100µA
= –1mA
= –10mA
= –50mA
= –100mA
= –200mA
GROUND CURRENT (µA)
–4.98
ILOAD
ILOAD
ILOAD
ILOAD
ILOAD
ILOAD
Figure 24. Output Voltage (VOUT) vs. Input Voltage (VIN) in Dropout, VOUT = −5 V
Rev. A | Page 10 of 28
Data Sheet
ADP7182
0
–1.780
–200
–1.790
VOUT (V)
–600
–800
–1.800
= –5mA
= –10mA
= –25mA
= –50mA
= –100mA
= –200mA
–1.805
–5.2
–5.0
–4.8
VIN (V)
Figure 25. Ground Current vs. Input Voltage (VIN) in Dropout, VOUT = −5 V
–1.810
–30
–1.780
–20
–15
–10
–5
0
Figure 28. Output Voltage (VOUT) vs. Input Voltage (VIN), VOUT = −1.8 V
0
= –100µA
= –1mA
= –10mA
= –50mA
= –100mA
= –200mA
–100
GROUND CURRENT (µA)
–1.775
–25
VIN (V)
–1.770
ILOAD
ILOAD
ILOAD
ILOAD
ILOAD
ILOAD
ILOAD = –50mA
ILOAD = –100mA
ILOAD = –200mA
ILOAD = –100µA
ILOAD = –1mA
ILOAD = –10mA
10703-028
–1600
–5.4
ILOAD
ILOAD
ILOAD
ILOAD
ILOAD
ILOAD
–1.785
–1.790
–1.795
–1.800
–200
–300
–400
ILOAD = –50mA
ILOAD = –100mA
ILOAD = –200mA
ILOAD = –100µA
ILOAD = –1mA
ILOAD = –10mA
–500
–600
–1.805
–40
–5
25
85
–700
10703-026
–1.810
125
JUNCTION TEMPERATURE (°C)
Figure 26. Output Voltage (VOUT) vs. Junction Temperature (TJ), VOUT = −1.8 V
–40
–5
25
85
10703-029
–1200
–1400
VOUT (V)
–1.795
–1000
10703-025
GROUND CURRENT (µA)
–1.785
–400
125
JUNCTION TEMPERATURE (°C)
Figure 29. Ground Current vs. Junction Temperature (TJ), VOUT = −1.8 V
–1.790
0
–100
GROUND CURRENT (µA)
VOUT (V)
–1.795
–1.800
–1.805
–200
–300
–400
–500
–150
–100
ILOAD (mA)
–50
0
Figure 27. Output Voltage (VOUT) vs. Load Current (ILOAD), VOUT = −1.8 V
Rev. A | Page 11 of 28
–700
–200
–150
–100
–50
0
ILOAD (mA)
Figure 30. Ground Current vs. Load Current (ILOAD), VOUT = −1.8 V
10703-030
–1.810
–200
10703-027
–600
ADP7182
Data Sheet
0
–1.20
–100
–400
ILOAD = –50mA
ILOAD = –100mA
ILOAD = –200mA
ILOAD = –100µA
ILOAD = –1mA
ILOAD = –10mA
–500
–1.22
–1.23
–1.24
–600
–25
–20
–15
–10
–5
0
VIN (V)
–1.25
–30
10703-031
–700
–30
Figure 31. Ground Current vs. Input Voltage (VIN), VOUT = −1.8 V
ILOAD
ILOAD
ILOAD
ILOAD
ILOAD
ILOAD
= –100µA
= –1mA
= –10mA
= –50mA
= –100mA
= –200mA
–25
–20
–15
–10
–5
0
VIN (V)
10703-034
–300
VOUT (V)
GROUND CURRENT (µA)
–1.21
–200
Figure 34. Output Voltage (VOUT) vs. Input Voltage (VIN), VOUT = −1.22 V
0
–1.20
–100
GROUND CURRENT (µA)
–1.22
–1.23
–1.25
= –100µA
= –1mA
= –10mA
= –50mA
= –100mA
= –200mA
–5
–40
–200
–300
–400
–500
ILOAD = –100µA
ILOAD = –1mA
ILOAD = –10mA
ILOAD = –50mA
ILOAD = –100mA
ILOAD = –200mA
–600
25
85
125
–700
JUNCTION TEMPERATURE (°C)
Figure 32. Output Voltage (VOUT) vs. Junction Temperature (TJ), VOUT = −1.22 V
–40
–5
25
85
10703-035
–1.24
ILOAD
ILOAD
ILOAD
ILOAD
ILOAD
ILOAD
10703-032
VOUT (V)
–1.21
125
JUNCTION TEMPERATURE (°C)
Figure 35. Ground Current vs. Junction Temperature (TJ), VOUT = −1.22 V
–1.20
0
–100
GROUND CURRENT (µA)
VOUT (V)
–1.21
–1.22
–1.23
–200
–300
–400
–500
–1.24
–150
–100
ILOAD (mA)
–50
0
Figure 33. Output Voltage (VOUT) vs. Load Current (ILOAD), VOUT = −1.22 V
Rev. A | Page 12 of 28
–700
–200
–150
–100
–50
0
ILOAD (mA)
Figure 36. Ground Current vs. Load Current (ILOAD), VOUT = −1.22 V
10703-036
–1.25
–200
10703-033
–600
Data Sheet
ADP7182
–14.80
0
–14.85
–100
–14.95
–400
–15.00
–15.05
–15.10
–15.15
–500
–15.20
–700
–30
ILOAD = –100µA
ILOAD = –1mA
ILOAD = –10mA
–25
–20
ILOAD = –50mA
ILOAD = –100mA
ILOAD = –200mA
–15
–15.25
–10
–5
0
VIN (V)
–15.30
–30
10703-037
–600
ILOAD
ILOAD
ILOAD
ILOAD
ILOAD
ILOAD
= –100µA
= –1mA
= –10mA
= –50mA
= –100mA
= –200mA
–25
–20
–15
VIN (V)
Figure 37. Ground Current vs. Input Voltage (VIN), VOUT = −1.22 V
Figure 40. Output Voltage (VOUT) vs. Input Voltage (VIN),
Adjustable Output Voltage, VOUT = −15 V
–14.80
0
–14.85
10703-040
–300
VOUT (V)
GROUND CURRENT (µA)
–14.90
–200
–100
GROUND CURRENT (µA)
–14.90
–15.00
–15.05
–15.10
–15.20
–15.25
–15.30
ILOAD
ILOAD
ILOAD
ILOAD
ILOAD
ILOAD
= –100µA
= –1mA
= –10mA
= –50mA
= –100mA
= –200mA
–40
–5
–200
–300
–400
–500
ILOAD = –100µA
ILOAD = –1mA
ILOAD = –10mA
–600
ILOAD = –50mA
ILOAD = –100mA
ILOAD = –200mA
–700
25
85
125
–800
JUNCTION TEMPERATURE (°C)
–40
–5
25
85
10703-041
–15.15
10703-038
VOUT (V)
–14.95
125
JUNCTION TEMPERATURE (°C)
Figure 38. Output Voltage (VOUT) vs. Junction Temperature (TJ),
Adjustable Output Voltage, VOUT = −15 V
Figure 41. Ground Current vs. Junction Temperature (TJ),
Adjustable Output Voltage, VOUT = −15 V
–14.80
0
–14.85
–100
GROUND CURRENT (µA)
–14.90
–15.00
–15.05
–15.10
–15.15
–200
–300
–400
–500
–600
–15.20
–15.30
–200
–150
–100
–50
ILOAD (mA)
0
Figure 39. Output Voltage (VOUT) vs. Load Current (ILOAD),
Adjustable Output Voltage, VOUT = −15 V
–800
–200
–150
–100
–50
ILOAD (mA)
Figure 42. Ground Current vs. Load Current (ILOAD),
Adjustable Output Voltage, VOUT = −15 V
Rev. A | Page 13 of 28
0
10703-042
–700
–15.25
10703-039
VOUT (V)
–14.95
Data Sheet
0
0
–100
–200
–200
–400
GROUND CURRENT (µA)
–300
–400
–500
ILOAD = –100µA
ILOAD = –1mA
ILOAD = –10mA
–600
ILOAD = –50mA
ILOAD = –100mA
ILOAD = –200mA
–20
–15
–800
–1000
–1200
VIN (V)
–1600
–15.0
10703-043
–25
–600
Figure 43. Ground Current vs. Input Voltage (VIN),
Adjustable Output Voltage, VOUT = −15 V
–14.8
–14.6
–14.4
–14.2
–14.0
VIN (V)
Figure 46. Ground Current vs. Input Voltage (VIN) in Dropout, VOUT = −15 V
0
0
–10
–20
–20
–40
ILOAD
ILOAD
ILOAD
ILOAD
= –200mA
= –100mA
= –10mA
= –1mA
100
1k
–30
PSRR (dB)
DROPOUT VOLTAGE (mV)
= –5mA
= –10mA
= –25mA
= –50mA
= –100mA
= –200mA
–1400
–700
–800
–30
ILOAD
ILOAD
ILOAD
ILOAD
ILOAD
ILOAD
10703-046
GROUND CURRENT (µA)
ADP7182
–60
–80
–40
–50
–60
–70
–100
–80
–120
10
100
1000
ILOAD (mA)
10703-044
10
0
–14.60
–14.65
–14.70
= –10mA
= –10mA
= –25mA
= –50mA
= –100mA
= –200mA
–10
–20
PSRR (dB)
–14.85
–14.90
ILOAD
ILOAD
ILOAD
ILOAD
= –200mA
= –100mA
= –10mA
= –1mA
100
1k
–50
–60
–70
–15.00
–80
–15.05
–90
–14.9
10M
–40
–14.95
–15.10
–15.0
1M
–30
–14.80
–14.8
–14.7
–14.6
–14.5
VIN (V)
10703-045
VOUT (V)
–14.75
100k
Figure 47. Power Supply Rejection Ratio (PSRR) vs. Frequency,
VOUT = −1.22 V vs. Different Load Currents (ILOAD), VIN = −2.7 V
Figure 44. Dropout Voltage vs. Load Current (ILOAD),
Adjustable Output Voltage, VOUT = −15 V
ILOAD
ILOAD
ILOAD
ILOAD
ILOAD
ILOAD
10k
FREQUENCY (Hz)
Figure 45. Output Voltage (VOUT) vs. Input Voltage (VIN) in Dropout,
Adjustable Output Voltage, VOUT = −15 V
–100
10
10k
100k
1M
10M
FREQUENCY (Hz)
Figure 48. Power Supply Rejection Ratio (PSRR) vs. Frequency,
VOUT = −1.22 V vs. Different Load Currents (ILOAD), VIN = −5.7 V
Rev. A | Page 14 of 28
10703-048
1
–100
10703-047
–90
–140
Data Sheet
ADP7182
–20
PSRR (dB)
–40
–60
–60
–70
–70
1.5
2.5
2.0
3.0
3.5
4.5
4.0
5.0
Figure 49. Power Supply Rejection Ratio (PSRR) vs. Headroom Voltage,
VOUT = −1.22 V, Load Current (ILOAD) = −200 mA
0
–10
–20
ILOAD
ILOAD
ILOAD
ILOAD
–80
1.0
0
–10
–20
–30
–40
–40
PSRR (dB)
–30
–60
–70
–80
–90
–90
–100
–100
1k
10k
100k
1M
10M
FREQUENCY (Hz)
10
–10
–20
ILOAD
ILOAD
ILOAD
ILOAD
0
–10
–20
–30
–40
–40
PSRR (dB)
–30
–50
–60
–80
–90
–90
10k
100k
1M
10M
FREQUENCY (Hz)
10703-051
–80
1k
100
1k
10k
100k
1M
10M
Figure 51. Power Supply Rejection Ratio (PSRR) vs. Frequency,
VOUT = −1.8 V vs. Different Load Currents (ILOAD), VIN = −5.5 V
ILOAD
ILOAD
ILOAD
ILOAD
= –200mA
= –100mA
= –10mA
= –1mA
100
1k
–60
–70
100
= –200mA
= –100mA
= –10mA
= –1mA
–50
–70
10
ILOAD
ILOAD
ILOAD
ILOAD
Figure 53. Power Supply Rejection Ratio (PSRR) vs. Frequency,
VOUT = −3 V vs. Different Load Currents (ILOAD), VIN = −4.0 V
= –200mA
= –100mA
= –10mA
= –1mA
–100
4.0
FREQUENCY (Hz)
Figure 50. Power Supply Rejection Ratio (PSRR) vs. Frequency,
VOUT = −1.8 V vs. Different Load Currents (ILOAD), VIN = −2.8 V
0
3.5
–60
–80
100
3.0
2.5
–50
–70
10
2.0
Figure 52. Power Supply Rejection Ratio (PSRR) vs. Headroom Voltage,
VOUT = −1.8 V, Load Current (ILOAD) = −200 mA
= –200mA
= –100mA
= –10mA
= –1mA
–50
1.5
HEADROOM VOLTAGE (V)
10703-050
PSRR (dB)
–40
–50
HEADROOM VOLTAGE (V)
PSRR (dB)
–30
–50
–80
1.0
FREQUENCY = 100Hz
FREQUENCY = 1kHz
FREQUENCY = 10kHz
FREQUENCY = 100kHz
FREQUENCY = 1MHz
FREQUENCY = 10MHz
10703-053
–30
10703-049
PSRR (dB)
–20
–10
–100
10
10k
100k
1M
10M
FREQUENCY (Hz)
Figure 54. Power Supply Rejection Ratio (PSRR) vs. Frequency,
VOUT = −3 V vs. Different Load Currents (ILOAD), VIN = −5.5 V
Rev. A | Page 15 of 28
10703-054
–10
0
FREQUENCY = 100Hz
FREQUENCY = 1kHz
FREQUENCY = 10kHz
FREQUENCY = 100kHz
FREQUENCY = 1MHz
FREQUENCY = 10MHz
10703-052
0
ADP7182
Data Sheet
0
0
FREQUENCY = 100Hz
FREQUENCY = 1kHz
FREQUENCY = 10kHz
FREQUENCY = 100kHz
FREQUENCY = 1MHz
FREQUENCY = 10MHz
–10
–20
FREQUENCY = 100Hz
FREQUENCY = 1kHz
FREQUENCY = 10kHz
FREQUENCY = 100kHz
FREQUENCY = 1MHz
FREQUENCY = 10MHz
–10
–20
PSRR (dB)
PSRR (dB)
–30
–40
–50
–30
–40
–50
–60
–60
–70
0
0.5
1.5
1.0
2.0
2.5
3.5
3.0
4.0
HEADROOM VOLTAGE (V)
Figure 55. Power Supply Rejection Ratio (PSRR) vs. Headroom Voltage,
VOUT = −3 V, Load Current (ILOAD) = −200 mA
0
–10
–20
ILOAD
ILOAD
ILOAD
ILOAD
–80
10703-055
–90
0
0.50
0.75
1.00
1.25
1.50
1.75
2.00
HEADROOM VOLTAGE (V)
Figure 58. Power Supply Rejection Ratio (PSRR) vs. Headroom Voltage,
Adjustable Output Voltage, VOUT = −15 V with Noise Reduction Network,
Load Current (ILOAD) = −200 mA
1000
= –200mA
= –100mA
= –10mA
= –1mA
VOUT = –3V
VOUT = –1.2V
VOUT = –15V ADJ
VOUT = –5V
VOUT = –1.8V
VOUT = –15V ADJ NR
NOISE (µV rms)
–30
PSRR (dB)
0.25
10703-058
–70
–80
–40
–50
–60
–70
100
10
–80
10
100
1k
10k
100k
1M
10M
FREQUENCY (Hz)
Figure 56. Power Supply Rejection Ratio (PSRR) vs. Frequency,
Adjustable Output Voltage, VOUT = −15 V vs. Different Load Currents (ILOAD),
VIN = −15.5 V with Noise Reduction Network
–10
–20
ILOAD
ILOAD
ILOAD
ILOAD
1
0.1
10
100
1000
Figure 59. RMS Noise vs. Load Current (ILOAD), Various Output Voltages
100k
= –200mA
= –100mA
= –10mA
= –1mA
–30
PSRR (dB)
0.01
LOAD CURRENT (mA)
NOISE SPECTRAL DENSITY (nV Hz)
0
1
0.001
10703-056
–100
10703-059
–90
–40
–50
–60
–70
–80
VOUT = –5V
VOUT = –1.8V
VOUT = –15V ADJ NR
VOUT = –3V
VOUT = –1.2V
VOUT = –15V ADJ
10k
1k
100
10
100
1k
10k
100k
FREQUENCY (Hz)
1M
10M
Figure 57. Power Supply Rejection Ratio (PSRR) vs. Frequency,
Adjustable Output Voltage, VOUT = −15 V vs. Different Load Currents (ILOAD),
VIN = −16.5 V with Noise Reduction Network
Rev. A | Page 16 of 28
1
1
10
100
1k
10k
100k
1M
10M
100M
FREQUENCY (Hz)
Figure 60. Noise Spectral Density, Various Output Voltages
10703-060
10
10703-057
–90
–100
Data Sheet
ADP7182
1
1
T
T
VOUT
2
VOUT
2
VIN
CH2 2mV
B
W
M10µs
A CH3
T 10.00%
2.52V
CH1 500mV BW
Figure 61. Line Transient Response, 500 mV Step, VOUT = −1.22 V, ILOAD = −200 mA
CH2 5mV
B
W
M2µs
A CH3
T 10.00%
1.60V
10703-064
CH1 500mV BW
10703-061
VIN
Figure 64. Line Transient Response, 500 mV Step, VOUT = −1.8 V, ILOAD = −10 mA
1
1
T
T
VOUT
2
VIN
VIN
VOUT
CH2 1mV
B
W
M10µs
A CH3
T 10.00%
2.52V
CH1 1V BW
Figure 62. Line Transient Response, 500 mV Step, VOUT = −1.22 V, ILOAD = −10 mA
CH2 5mV
B
W
M4µs
A CH3
T 10.00%
1.60V
10703-065
CH1 500mV BW
10703-062
2
Figure 65. Line Transient Response, 500 mV Step, VOUT = −3 V, ILOAD = −200 mA
1
1
T
T
VOUT
2
VIN
VIN
CH2 5mV
B
W
M2µs
A CH3
T 10.00%
1.60V
10703-063
CH1 500mV BW
CH1 1V BW
Figure 63. Line Transient Response, 500 mV Step, VOUT = −1.8 V, ILOAD = −200 mA
CH2 5mV
B
W
M4µs
A CH3
T 10.00%
1.60V
10703-066
VOUT
2
Figure 66. Line Transient Response, 500 mV Step, VOUT = −3 V, ILOAD = −10 mA
Rev. A | Page 17 of 28
ADP7182
Data Sheet
1
T
T
1
VIN
VOUT
VIN
VOUT
CH1 1V BW
CH2 10mV
B
W
M2µs
A CH3
T 10.00%
2.02V
10703-067
2
CH1 1V BW
Figure 67. Line Transient Response, 500 mV Step, VOUT = −5 V, ILOAD = −200 mA
CH2 2mV
B
M10µs
A CH3
T 10.00%
W
2.52V
10703-070
2
Figure 70. Line Transient Response, 500 mV Step, VOUT = −15 V,
Noise Reduction Network, ILOAD = −10 mA
1
T
T
VOUT
2
VOUT
2
1
VIN
CH2 5mV
B
W
M2µs
A CH3
T 10.00%
2.02V
CH1 100mA BW CH2 50mV
Figure 68. Line Transient Response, 500 mV Step, VOUT = −5 V, ILOAD = −10 mA
W
M40µs A CH1
T 10.40%
–122mA
Figure 71. Load Transient Response, VOUT = −1.22 V, ILOAD = −1 mA to −200 mA,
Load Step = 1 A/µs
T
1
B
10703-071
CH1 1V BW
10703-068
LOAD CURRENT
T
VIN
VOUT
2
1
VOUT
2
CH2 2mV
B
W
M4µs
A CH3
T 10.00%
2.52V
Figure 69. Line Transient Response, 500 mV Step, VOUT = −15 V,
Noise Reduction Network, ILOAD = −200 mA
CH1 100mA BW
CH2 50mV
B
W M40µs A CH1
T 10.60%
–122mA
10703-072
CH1 1V BW
10703-069
LOAD CURRENT
Figure 72. Load Transient Response, VOUT = −3 V, ILOAD = −1 mA to −200 mA,
Load Step = 1 A/µs
Rev. A | Page 18 of 28
Data Sheet
ADP7182
T
T
VOUT
VOUT
2
2
1
1
CH2 50mV
B
W M10µs A CH1
T 10.00%
–122mA
10703-073
CH1 100mA BW
CH1 100mA BW
CH2 50mV
B
W M40µs A CH1
T 10.00%
Figure 73. Load Transient Response, VOUT = −5 V, ILOAD = −1 mA to −200 mA,
Load Step = 1 A/µs
–122mA
10703-074
LOAD CURRENT
LOAD CURRENT
Figure 74. Load Transient Response, VOUT = −15 V, ILOAD = −1 mA to −200 mA,
Load Step = 1 A/µs, Noise Reduction Network
Rev. A | Page 19 of 28
ADP7182
Data Sheet
THEORY OF OPERATION
The ADP7182 is a low quiescent current, LDO linear regulator
that operates from −2.7 V to −28 V and can provide up to −200 mA
of output current. Drawing a low −650 µA of quiescent current
(typical) at full load makes the ADP7182 ideal for battery-powered
portable equipment. Maximum shutdown current consumption
is −8 µA at room temperature.
Optimized for use with small 2.2 µF ceramic capacitors, the
ADP7182 provides excellent transient performance.
R2
−VOUT = −1.22 V (1 + RFB1/RFB2)
SHUTDOWN
R1
VOUT
VIN
Figure 75. Fixed Output Voltage Internal Block Diagram
GND
VREG
SHORT
CIRCUIT
THERMAL
PROTECT
–1.22V
REFERENCE
SHUTDOWN
VOUT
10703-076
VIN
For example, when RFB1 = RFB2 = 120 kΩ, the output voltage is
−2.44 V and the error due to the typical ADJ pin leakage current
(10 nA) is 60 kΩ times 10 nA, or 6 mV. This example results in
an output voltage error of 0.245%.
The addition of a small capacitor (~100 pF) in parallel with
RFB1 can improve the stability of the ADP7182. Larger values of
capacitance also reduce the noise and improve PSRR (see the
Noise Reduction of the Adjustable ADP7182 section).
ADJ
EN
RFB2 must be less than 120 kΩ to minimize the output voltage errors
due to the leakage current of the ADJ pin. The error voltage
caused by the ADJ pin leakage current is the parallel combination
of RFB1 and RFB2 times the ADJ pin leakage current.
CIN
2.2µF
Figure 76. Adjustable Output Voltage Internal Block Diagram
Internally, the ADP7182 consists of a reference, an error amplifier,
a feedback voltage divider, and an NMOS pass transistor.
Output current is delivered via the NMOS pass transistor,
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
more positive than the reference voltage, the gate of the NMOS
transistor is pulled toward GND, allowing more current to pass
and increasing the output voltage. If the feedback voltage is more
negative than the reference voltage, the gate of the NMOS
transistor is pulled toward −VIN, allowing less current to pass
and decreasing the output voltage.
COUT
2.2µF
GND
VIN = –3V
ON
OFF
–2V
The ESD protection devices are shown in the block diagram as
Zener diodes (see Figure 75 and Figure 76).
Rev. A | Page 20 of 28
VIN
2V
0V
VOUT
RFB2
120kΩ
RFB1
120kΩ
VOUT = –2.44V
ADP7182
EN
ADJ
ON
Figure 77. Setting Adjustable Output Voltage
10703-077
EN
ADJUSTABLE MODE OPERATION
REFERENCE
10703-075
VREG
The ADP7182 uses the EN pin to enable and disable the VOUT
pin under normal operating conditions. When EN is at ±2 V with
respect to GND, VOUT turns on, and when EN is at 0 V, VOUT
turns off. For automatic startup, EN can be connected to VIN.
The ADP7182 is available in a fixed output voltage and an
adjustable mode version with an output voltage that can be set
to between −1.22 V and −27 V by an external voltage divider. The
output voltage can be set according to
GND
SHORT
CIRCUIT
THERMAL
PROTECT
ENABLE PIN OPERATION
Data Sheet
ADP7182
APPLICATIONS INFORMATION
ADIsimPower DESIGN TOOL
The ADP7182 is supported by the ADIsimPower™ design tool
set. ADIsimPower is a collection of tools that produce complete
power designs optimized for a specific design goal. The tools
enable the user to generate a full schematic, bill of materials,
and calculate performance in minutes. ADIsimPower can
optimize designs for cost, area, efficiency, and parts count
taking into consideration the operating conditions and
limitations of the IC and all real external components. For
more information about, and to obtain ADIsimPower
design tools, visit www.analog.com/ADIsimPower.
CAPACITOR SELECTION
Output Capacitor
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 25 V or 50 V are recommended. Due to
their poor temperature and dc bias characteristics, Y5V and Z5U
dielectrics are not recommended.
Figure 79 depicts the capacitance vs. voltage bias characteristics
of an 0805, 2.2 µF, 25 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
2.0
CAPACITANCE (µF)
1.5
1.0
0.5
0
0
T
5
10
15
20
25
DC BIAS (V)
30
10703-079
The ADP7182 is designed for operation with small space-saving
ceramic capacitors; however, it functions with most commonly
used capacitors as long as care is taken with regard to the 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 0.2 Ω or less is recommended to ensure the stability of
the ADP7182. 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 ADP7182
to large changes in load current. Figure 78 shows the transient
responses for an output capacitance value of 2.2 µF.
Figure 79. Capacitance vs. DC Bias Characteristics
Use Equation 1 to determine the worst-case capacitance accounting
for capacitor variation over temperature, component tolerance,
and voltage.
VOUT
2
CEFF = CBIAS × (1 − TEMPCO) × (1 − TOL)
1
where:
CBIAS is the effective capacitance at the operating voltage, which
is −3 V for this example.
TEMPCO is the worst-case capacitor temperature coefficient.
TOL is the worst-case component tolerance.
CH2 50mV
B
W M40µs A CH1
–122mA
T 10.60%
10703-078
LOAD CURRENT
CH1 100mA BW
(1)
Figure 78. Output Transient Response, COUT = 2.2 µF
Input Bypass Capacitor
Connecting a 2.2 µF capacitor from VIN to GND reduces the
circuit sensitivity to PCB layout, especially when long input
traces or high source impedance are encountered. When more
than 2.2 µF of output capacitance is required, increase the input
capacitance to match it.
Input and Output Capacitor Properties
As long as they meet the minimum capacitance and maximum
ESR requirements, any good quality ceramic capacitors can be
used with the ADP7182. Ceramic capacitors are manufactured
with a variety of dielectrics, each with different behavior over
In this example, the worst-case temperature coefficient (TEMPCO)
over −40°C to +85°C is 15% for an X5R dielectric. The tolerance
of the capacitor (TOL) is 10%, and the CBIAS is 2.08 µF at a 3 V bias,
as shown in Figure 79.
Substituting these values in Equation 1 yields
CEFF = 2.08 μF × (1 − 0.15) × (1 − 0.1) = 1.59 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 of −3 V.
To guarantee the performance of the ADP7182, 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 21 of 28
ADP7182
Data Sheet
ENABLE PIN OPERATION
T
EN
The ADP7182 provides a dual polarity enable pin (EN) that turns
on the LDO when |VEN| ≥ 2 V. The enable voltage can be positive or
negative with respect to ground.
1
0
VOUT
2
–1.0
CH1 500mV BW
–1.5
CH2 500mV BW
M40µs A CH1
T 10.20%
10703-082
VOUT (V)
–0.5
590mV
Figure 82. Typical Start-Up Behavior, Positive Going Enable
VOUT WITH RISING VEN
–1.5
–1.0
–0.5
1
0
0.5
1.0
1.5
ENABLE VOLTAGE (V)
10703-080
–2.0
–2.0
T
VOUT WITH FALLING VEN
Figure 80. Typical EN Pin Operation
EN
Figure 80 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.
VOUT
2
Figure 81 shows typical EN thresholds when the input voltage
varies from −2.7 V to −28 V.
CH1 500mV BW
ENABLE THRESHOLD (V)
0.5
CH2 500mV BW
M40µs A CH1
T 10.20%
10703-083
1.0
–580mV
Figure 83. Typical Start-Up Behavior, Negative Going Enable
0
ENABLE+
DISABLE+
ENABLE–
DISABLE–
–0.5
SOFT START
The ADP7182 uses an internal soft start to limit the inrush current
when the output is enabled. The start-up time for the −5 V option
is approximately 450 µs from the time the EN active threshold is
crossed to when the output reaches 90% of its final value. As shown
in Figure 84, the start-up time is dependent on the output voltage
setting.
–1.0
–2.0
–30
–26
–22
–18
–14
–10
–6
INPUT VOLTAGE (V)
–2
2
10703-081
–1.5
1
0
–1
–2
–3
–4
VEN
VOUT = –1.22V
VOUT = –3V
VOUT = –5V
–5
–6
0
100
200
300
400
500
600
700
800
900
1000
TIME (µs)
Figure 84. Typical Start-Up Behavior, Different Output Voltages
Rev. A | Page 22 of 28
10703-084
Figure 82 and Figure 83 show the start-up behavior for a −5 V
output with positive and negative going enable signals.
OUTPUT VOLTAGES (V)
Figure 81. Typical EN Pin Thresholds vs. Input Voltage
Data Sheet
ADP7182
NOISE REDUCTION OF THE ADJUSTABLE ADP7182
CNR is chosen by setting the reactance of CNR equal to RFB1 − RNR
at a frequency between 10 Hz and 100 Hz. This capacitance sets
the frequency where the ac gain of the error amplifier is 3 dB down
from its dc gain.
COUT
2.2µF
CIN
2.2µF
GND
ON
OFF
–2V
VIN
2V
0V
VOUT
RFB1
147kΩ
RNR
13kΩ
CNR
100nF
VOUT = –15V
ADP7182
EN
ADJ
ON
10703-085
VIN = –16V
RFB2
13kΩ
Figure 85. Noise Reduction Modification to Adjustable LDO
The noise of the LDO is approximately the noise of the fixed output
LDO (typically 18 µV rms) times RFB2, divided by the parallel
combination of RNR and RFB1. Based on the component values
shown in Figure 85, the ADP7182 has the following characteristics:
•
•
•
•
•
•
•
DC gain of 12.3 (21.8 dB)
3 dB roll-off frequency of 10.8 Hz
High frequency ac gain of 1.92 (5.67 dB)
Noise reduction factor of 6.41 (16.13 dB)
Measured rms noise of the adjustable LDO at −200 mA
without noise reduction of 220 µV rms
Measured rms noise of the adjustable LDO at −200 mA
with noise reduction circuit of 35 µV rms
Calculated rms noise of the adjustable LDO with noise
reduction (assuming 18 µV rms for fixed voltage option) of
34.5 µV rms
The noise of the LDO is approximately the noise of the fixed output
LDO (typically 18 µV rms) times the high frequency ac gain. The
following equation shows the calculation with the values shown
in Figure 85.
100k
–15V ADJ
–15V ADJ NR
10k
1k
100
10
1
1
10
100
1k
10k
100k
1M
10M
100M
FREQUENCY (Hz)
10703-086
The adjustable LDO circuit can be modified slightly to reduce
the output voltage noise to levels close to that of the fixed output of
the ADP7182. The circuit shown in Figure 85 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 nearly 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 resistance ensures that the error amplifier always
operates at greater than unity gain.
(2)
Figure 86 shows the difference in noise spectral density for the
adjustable ADP7182 set to −15 V with and without the noise
reduction network. In the 100 Hz to 30 kHz frequency range,
the reduction in noise is significant.
NOISE SPECTRAL DENSITY (nV Hz)
The ultralow output noise of the fixed output ADP7182 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 ADP7182 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.
 


1
/13 kΩ 
18 µV × 1 + 
  1/13 kΩ + 1/147 kΩ 


 

Figure 86. −15 V Adjustable ADP7182 with and without the
Noise Reduction Network (CNR and RNR)
CURRENT-LIMIT AND THERMAL OVERLOAD
PROTECTION
The ADP7182 is protected against damage due to excessive power
dissipation by current-limit and thermal overload protection
circuits. The ADP7182 is designed to limit current when the
output load reaches −350 mA (typical). When the output load
exceeds −350 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 power
dissipation) when the junction temperature starts to rise above
150°C, the output is turned off, reducing the output current to
0 mA. When the junction temperature falls below 135°C, the
output is turned on again, and the output current is restored to
its nominal value.
Consider the case where a hard short from VOUT to ground
occurs. At first, the ADP7182 limits current so that only −350 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 is activated, turning off the output and reducing the
output current to 0 mA. As the junction temperature cools and
falls below 135°C, the output turns on and conducts −350 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 −350 mA and 0 mA that
continues as long as the short remains at the output.
Current-limit and thermal overload protections are intended to
protect the device against accidental overload conditions. For
Rev. A | Page 23 of 28
ADP7182
Data Sheet
THERMAL CONSIDERATIONS
In most applications, the ADP7182 does not dissipate much heat
due to its high efficiency. However, in applications with high
ambient temperature, and high supply voltage to output voltage
differential, the heat dissipated in the package is large enough that
it can cause the junction temperature of the die to exceed the
maximum junction temperature of 125°C.
When the junction temperature exceeds 150°C, the converter
enters thermal shutdown. It recovers only after the junction
temperature has decreased below 135°C to prevent any permanent
damage. Therefore, thermal analysis for the chosen application
is 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 3.
To guarantee reliable operation, the junction temperature of the
ADP7182 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 7. Typical θJA Values of the 8-Lead LFCSP
Copper Size (mm2)
251
100
500
1000
6400
1
θJA (°C/W)
175
135.6
77.3
65.2
51
Device soldered to minimum size pin traces.
TJ = TA + (PD × θJA)
PD = [(VIN − VOUT) × ILOAD] + (VIN × IGND)
1
Power dissipation due to ground current is quite small and can be
ignored. Therefore, the junction temperature equation simplifies to
TJ = TA + {[(VIN − VOUT) × ILOAD] × θJA}
(5)
As shown in Equation 5, for a given ambient temperature, input-tooutput 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 87
to Figure 92 show junction temperature calculations for different
ambient temperatures, power dissipation, and areas of PCB copper.
Heat dissipation from the package can be improved by increasing
the amount of copper attached to the pins of the ADP7182.
Adding thermal planes under the package also improves thermal
performance. However, as listed in Table 7 and Table 8, a point
of diminishing returns is reached eventually, beyond which an
increase in the copper area does not yield significant reduction
in the junction-to-ambient thermal resistance.
140
θJA (°C/W)
170
152
146
134
131
120
100
80
60
6400mm 2
1000mm 2
500mm 2
100mm 2
25mm 2
JEDEC
TJ MAX
40
20
0
0
0.2
0.4
0.6
0.8
1.0
1.2
TOTAL POWER DISSIPATION (W)
Figure 87. Junction Temperature vs. Total Power Dissipation for the
8-Lead LFCSP, TA = 25°C
Device soldered to minimum size pin traces.
Table 9. Typical ΨJB Values
Model
8-lead LFCSP
5-lead TSOT
(4)
where:
VIN and VOUT are the input and output voltages, respectively.
ILOAD is the load current.
IGND is the ground current.
Table 8. Typical θJA Values of the 5-Lead TSOT
Copper Size (mm2)
01
50
100
300
500
(3)
where:
TA is the ambient temperature.
PD is the power dissipation in the die, given by
JUNCTION TEMPERATURE, TJ (°C)
Table 7 and Table 8 show typical θJA values of the 8-lead LFCSP
and 5-lead TSOT packages for various PCB copper sizes. Table 9
shows the typical ΨJB values of the 8-lead LFCSP and 5-lead TSOT.
The junction temperature of the ADP7182 can be calculated by
ΨJB (°C/W)
18.2
43
Rev. A | Page 24 of 28
10703-087
reliable operation, device power dissipation must be externally
limited so that the junction temperatures do not exceed 125°C.
ADP7182
140
120
120
100
80
60
6400mm 2
1000mm 2
500mm 2
100mm 2
25mm 2
JEDEC
TJ MAX
20
0
0
0.2
0.4
0.6
0.8
1.0
1.2
TOTAL POWER DISSIPATION (W)
500mm 2
40
300mm 2
100mm 2
20
25mm 2
JEDEC
120
JUNCTION TEMPERATURE, TJ (°C)
120
100
80
60
6400mm 2
1000mm 2
500mm 2
100mm 2
25mm 2
JEDEC
TJ MAX
0
0
0.2
0.4
0.6
0.8
1.0
1.2
TOTAL POWER DISSIPATION (W)
Figure 89. Junction Temperature vs. Total Power Dissipation for the
8-Lead LFCSP, TA = 85°C
120
100
80
60
500mm 2
300mm 2
100mm 2
20
25mm 2
JEDEC
0
0.2
0.4
0.6
0.8
1.0
1.2
TOTAL POWER DISSIPATION (W)
10703-090
TJ MAX
0
0.3
0.4
0.5
0.6
0.7
100
80
60
500mm 2
40
300mm 2
100mm 2
20
25mm 2
JEDEC
TJ MAX
0
0
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
TOTAL POWER DISSIPATION (W)
Figure 92. Junction Temperature vs. Total Power Dissipation for the
5-Lead TSOT, TA = 85°C
140
40
0.2
Figure 91. Junction Temperature vs. Total Power Dissipation for the
5-Lead TSOT, TA = 50°C
140
20
0.1
TOTAL POWER DISSIPATION (W)
140
40
TJ MAX
0
10703-089
JUNCTION TEMPERATURE, TJ (°C)
60
0
Figure 88. Junction Temperature vs. Total Power Dissipation for the
8-Lead LFCSP, TA = 50°C
JUNCTION TEMPERATURE, TJ (°C)
80
Figure 90. Junction Temperature vs. Total Power Dissipation for the
5-Lead TSOT, TA = 25°C
Rev. A | Page 25 of 28
10703-092
40
100
10703-091
JUNCTION TEMPERATURE, TJ (°C)
140
10703-088
JUNCTION TEMPERATURE, TJ (°C)
Data Sheet
ADP7182
Data Sheet
Thermal Characterization Parameter, ΨJB
PCB LAYOUT CONSIDERATIONS
When the board temperature is known, use the thermal
characterization parameter, ΨJB, to estimate the junction
temperature rise (see Figure 93 and Figure 94). Maximum
junction temperature (TJ) is calculated from the board temperature
(TB) and power dissipation (PD) using the following formula:
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 1206 or 0805 size capacitors and resistors
achieves the smallest possible footprint solution on boards where
area is limited.
TJ = TB + (PD × ΨJB)
(6)
The typical value of ΨJB is 18.2°C/W for the 8-lead LFCSP package
and 43°C/W for the 5 lead TSOT package.
120
100
80
60
40
TB = 25°C
TB = 50°C
TB = 85°C
TJ MAX
0
0
1
2
3
4
5
6
7
TOTAL POWER DISSIPATION (W)
Figure 93. Junction Temperature vs. Total Power Dissipation for the
8-Lead LFCSP, TA = 85°C
Figure 95. Example of the 8-Lead LFCSP PCB Layout
140
120
100
80
60
40
TB = 25°C
TB = 50°C
TB = 85°C
TJ MAX
20
0
0
1
2
3
4
5
TOTAL POWER DISSIPATION (W)
6
7
10703-094
JUNCTION TEMPERATURE, TJ (°C)
10703-095
20
10703-093
JUNCTION TEMPERATURE, TJ (°C)
140
10703-096
Figure 94. Junction Temperature vs. Total Power Dissipation for the
5-Lead TSOT, TA = 85°C
Figure 96. Example of the 5-Lead TSOT PCB Layout
Rev. A | Page 26 of 28
Data Sheet
ADP7182
OUTLINE DIMENSIONS
2.48
2.38
2.23
8
5
EXPOSED
PAD
INDEX
AREA
0.50
0.40
0.30
SEATING
PLANE
4
TOP VIEW
1
BOTTOM VIEW
0.80 MAX
0.55 NOM
0.80
0.75
0.70
0.30
0.25
0.18
0.50 BSC
1.74
1.64
1.49
0.05 MAX
0.02 NOM
COPLANARITY
0.08
0.20 REF
0.20 MIN
PIN 1
INDICATOR
(R 0.2)
FOR PROPER CONNECTION OF
THE EXPOSED PAD, REFER TO
THE PIN CONFIGURATION AND
FUNCTION DESCRIPTIONS
SECTION OF THIS DATA SHEET.
COMPLIANT TO JEDEC STANDARDS MO-229-WEED-4
02-05-2013-B
3.10
3.00 SQ
2.90
Figure 97. 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
ORDERING GUIDE
Model 1
ADP7182ACPZ-R7
ADP7182ACPZ-5.0-R7
ADP7182CP-EVALZ
1
2
Temperature Range
−40°C to +125°C
−40°C to +125°C
Output Voltage (V) 2
Adjustable
−5
Package Description
8-Lead LFCSP_WD
8-Lead LFCSP_WD
Evaluation Board
Z = RoHS Compliant Part.
For additional voltage options, contact a local Analog Devices, Inc., sales or distribution representative.
Rev. A | Page 27 of 28
Package Option
CP-8-5
CP-8-5
Branding
LN6
LN9
ADP7182
Data Sheet
NOTES
©2013 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D10703-0-5/13(A)
Rev. A | Page 28 of 28