Transcript
Zero Drift, Digitally Programmable Instrumentation Amplifier AD8231-EP
ENHANCED PRODUCT FEATURES Supports defense and aerospace applications (AQEC standard) Military temperature range (−55°C to +125°C) Controlled manufacturing baseline One assembly/test site One fabrication site Enhanced product change notification Qualification data available on request
–INA +INA NC
CS 13
A0 14
15
16 NC
A1
FUNCTIONAL BLOCK DIAGRAM
1
12 LOGIC
2
11
IN-AMP
3
10
4
9
+VS –VS OUTA REF
AD8231-EP OP
09707-001
8 OUTB
7 –INB
6 +INB
5
AMP
SDN
Digitally/pin-programmable gain G = 1, 2, 4, 8, 16, 32, 64, or 128 Specified from −55°C to +125°C 50 nV/°C maximum input offset drift 10 ppm/°C maximum gain drift Excellent dc performance 80 dB minimum CMR, G = 1 15 μV maximum input offset voltage 500 pA maximum bias current 0.7 μV p-p noise (0.1 Hz to 10 Hz) Good ac performance 2.7 MHz bandwidth, G = 1 1.1 V/μs slew rate Rail-to-rail output Shutdown/multiplex Extra op amp Single-supply range: 3 V to 6 V Dual-supply range: ±1.5 V to ±3 V
A2
FEATURES
Figure 1.
Table 1. Instrumentation and Difference Amplifiers by Category High Performance AD8221 AD82201 AD8222 AD82241
1
Low Cost AD623 1 AD85531
High Voltage AD628 AD629
Mil Grade AD620 AD621 AD524 AD526 AD624
Low Power AD6271
Digital Gain AD82311 AD8250 AD8251 AD85551 AD85561 AD85571
Rail-to-rail output.
GENERAL DESCRIPTION The AD8231-EP is a low drift, rail-to-rail, instrumentation amplifier with software-programmable gains of 1, 2, 4, 8, 16, 32, 64, or 128. The gains are programmed via digital logic or pin strapping.
The AD8231-EP also includes an uncommitted op amp that can be used for additional gain, differential signal driving, or filtering. Like the in-amp, the op amp has an auto-zero architecture, railto-rail input, and rail-to-rail output.
The AD8231-EP is ideal for applications that require precision performance over a wide temperature range, such as industrial temperature sensing and data logging. Because the gain setting resistors are internal, maximum gain drift is only 10 ppm/°C for gains of 1 to 32. Because of the auto-zero input stage, maximum input offset is 15 μV and maximum input offset drift is just 50 nV/°C. CMRR is 80 dB for G = 1, increasing to 110 dB at higher gains.
The AD8231-EP includes a shutdown feature that reduces current to a maximum of 1 μA. In shutdown, both amplifiers also have a high output impedance, which allows easy multiplexing of multiple amplifiers without additional switches. The AD8231-EP is specified over the military temperature range of −55°C to +125°C. It is available in a 4 mm × 4 mm 16lead LFCSP. Additional application and technical information can be found in the AD8231 data sheet.
Rev. 0 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.
AD8231-EP TABLE OF CONTENTS Features .............................................................................................. 1
ESD Caution...................................................................................7
Enhanced Product Features ............................................................ 1
Pin Configuration and Function Descriptions..............................8
Functional Block Diagram .............................................................. 1
Typical Performance Characteristics ..............................................8
General Description ......................................................................... 1
Instrumentation Amplifier Performance Curves......................9
Revision History ............................................................................... 2
Operational Amplifier Performance Curves .......................... 15
Specifications..................................................................................... 3
Performance Curves Valid for Both Amplifiers ..................... 17
Absolute Maximum Ratings............................................................ 7
Outline Dimensions ....................................................................... 18
Thermal Resistance ...................................................................... 7
Ordering Guide .......................................................................... 18
Maximum Power Dissipation ..................................................... 7
REVISION HISTORY 5/11—Revision 0: Initial Version
Rev. 0 | Page 2 of 20
AD8231-EP SPECIFICATIONS VS = 5 V, VREF = 2.5 V, G = 1, RL = 10 kΩ, TA = 25°C, unless otherwise noted. Table 2. Parameter INSTRUMENTATION AMPLIFIER Offset Voltage Input Offset, VOSI Average Temperature Drift Output Offset, VOSO Average Temperature Drift Input Currents Input Bias Current
Test Conditions/Comments
Min
Typ
Max
Unit
4 0.01 15 0.05
15 0.05 30 0.5
μV μV/°C μV μV/°C
250
500 5 100 0.5
pA nA pA nA
0.05 0.8
% %
10 20 30
ppm/°C ppm/°C ppm/°C ppm ppm
VOS RTI = VOSI + VOSO/G TA = −55°C to +125°C TA = −55°C to +125°C
TA = −55°C to +125°C Input Offset Current Gains Gain Error G=1 G = 2 to 128 Gain Drift G = 1 to 32 G = 64 G = 128 Linearity CMRR G=1 G=2 G=4 G=8 G = 16 G = 32 G = 64 G = 128 Noise Input Voltage Noise, eni
Output Voltage Noise, eno
Current Noise Other Input Characteristics Common-Mode Input Impedance Power Supply Rejection Ratio Input Operating Voltage Range Reference Input Input Impedance Voltage Range
20 TA = −55°C to +125°C 1, 2, 4, 8, 16, 32, 64, or 128
TA = −55°C to +125°C 3 4 10 3 5
0.2 V to 4.8 V, 10 kΩ load 0.2 V to 4.8 V, 2 kΩ load 80 86 92 98 104 110 110 110 en = √(eni2 + (eno/G)2), VIN+, VIN− = 2.5 V f = 1 kHz f = 1 kHz, TA = −55°C f = 1 kHz, TA = 125°C f = 0.1 Hz to 10 Hz f = 1 kHz f = 1 kHz, TA = −55°C f = 1 kHz, TA = 125°C f = 0.1 Hz to 10 Hz f = 10 Hz
100 0.05
dB dB dB dB dB dB dB dB 32 27 39 0.7 58 50 70 1.1 20
nV/√Hz nV/√Hz nV/√Hz μV p-p nV/√Hz nV/√Hz nV/√Hz μV p-p fA/√Hz
10||5 115 4.95
GΩ||pF dB V
+5.2
kΩ V
28 −0.2
Rev. 0 | Page 3 of 20
AD8231-EP Parameter Dynamic Performance Bandwidth G=1 G=2 Gain Bandwidth Product G = 4 to 128 Slew Rate Output Characteristics Output Voltage High Output Voltage Low Short-Circuit Current Digital Interface Input Voltage Low Input Voltage High Setup Time to CS High Hold Time after CS High OPERATIONAL AMPLIFIER Input Characteristics Offset Voltage, VOS Temperature Drift Input Bias Current
Test Conditions/Comments
RL = 100 kΩ to ground RL = 10 kΩ to ground RL = 100 kΩ to 5 V RL = 10 kΩ to 5 V
TA = −55°C to +125°C TA = −55°C to +125°C TA = −55°C to +125°C TA = −55°C to +125°C
Min
4.9 4.8
Typ
MHz MHz
7 1.1
MHz V/μs
4.94 4.88 60 80 70
V V mV mV mA
1.0
V V ns ns
15 0.06 500 5 100 0.5 4.95
120 120 110 20 0.4
μV μV/°C pA nA pA nA V V/mV dB dB nV/√Hz μV p-p
1 0.5
MHz V/μs
4.96 4.92 60 80 70
V V mV mV mA
5 0.01 250
Input Offset Current
20 TA = −55°C to +125°C
Output Voltage Low
0.05 100 100 100 f = 0.1 Hz to 10 Hz
RL = 100 kΩ to ground RL = 10 kΩ to ground RL = 100 kΩ to 5 V RL = 10 kΩ to 5 V
Short-Circuit Current BOTH AMPLIFIERS Power Supply Quiescent Current Quiescent Current (Shutdown)
4.9 4.8
4 0.01
Rev. 0 | Page 4 of 20
100 200
4.0 50 20
TA = −55°C to +125°C
Unit
2.7 2.5
TA = −55°C to +125°C
Input Voltage Range Open-Loop Gain Common-Mode Rejection Ratio Power Supply Rejection Ratio Voltage Noise Density Voltage Noise Dynamic Performance Gain Bandwidth Product Slew Rate Output Characteristics Output Voltage High
Max
100 200
5 1
mA μA
AD8231-EP VS = 3.0 V, VREF = 1.5 V, TA = 25°C, G = 1, RL = 10 kΩ, unless otherwise noted. Table 3. Parameter INSTRUMENTATION AMPLIFIER Offset Voltage Input Offset, VOSI Average Temperature Drift Output Offset, VOSO Average Temperature Drift Input Currents Input Bias Current
Conditions
Min
Typ
Max
Unit
4 0.01 15 0.05
15 0.05 30 0.5
μV μV/°C μV μV/°C
250
500 5 100 0.5
pA nA pA nA
0.05 0.8
% %
10 20 30
ppm/°C ppm/°C ppm/°C
VOS RTI = VOSI + VOSO/G
TA = −55°C to +125°C Input Offset Current Gains Gain Error G=1 G = 2 to 128 Gain Drift G = 1 to 32 G = 64 G = 128 CMRR G=1 G=2 G=4 G=8 G = 16 G = 32 G = 64 G = 128 Noise Input Voltage Noise, eni
Output Voltage Noise, eno
Current Noise Other Input Characteristics Common-Mode Input Impedance Power Supply Rejection Ratio Input Operating Voltage Range Reference Input Input Impedance Voltage Range
20 TA = −55°C to +125°C 1, 2, 4, 8, 16, 32, 64, or 128
TA = −55°C to +125°C 3 4 10 80 86 92 98 104 110 110 110 en = √(eni2 + (eno/G)2) VIN+, VIN− = 2.5 V, TA = 25°C f = 1 kHz f = 1 kHz, TA = −55°C f = 1 kHz, TA = 125°C f = 0.1 Hz to 10 Hz f = 1 kHz f = 1 kHz, TA = −55°C f = 1 kHz, TA = 125°C f = 0.1 Hz to 10 Hz f = 10 Hz
100 0.05
dB dB dB dB dB dB dB dB
40 35 48 0.8 72 62 83 1.4 20
nV/√Hz nV/√Hz nV/√Hz μV p-p nV/√Hz nV/√Hz nV/√Hz μV p-p fA/√Hz
10||5 115 2.95
GΩ||pF dB V
+3.2
kΩ||pF V
28 −0.2
Rev. 0 | Page 5 of 20
AD8231-EP Parameter Dynamic Performance Bandwidth G=1 G=2 Gain Bandwidth Product G = 4 to 128 Slew Rate Output Characteristics Output Voltage High Output Voltage Low Short-Circuit Current Digital Interface Input Voltage Low Input Voltage High Setup Time to CS High Hold Time after CS High OPERATIONAL AMPLIFIERS Input Characteristics Offset Voltage, VOS Temperature Drift Input Bias Current
Conditions
RL = 100 kΩ to ground RL = 10 kΩ to ground RL = 100 kΩ to 3 V RL = 10 kΩ to 3 V
TA = −55°C to +125°C TA = −55°C to +125°C TA = −55°C to +125°C TA = −55°C to +125°C
Min
2.9 2.8
Typ
MHz MHz
7 1.1
MHz V/μs
2.94 2.88 60 80 40
V V mV mV mA V V ns ns
15 0.06 500 5 100 0.5 2.95
120 120 110 27 0.6
μV μV/°C pA nA pA nA V V/mV dB dB nV/√Hz μV p-p
1 0.5
MHz V/μs
2.96 2.82 60 80 40
V V mV mV mA
TA = −55°C to +125°C 20 TA = −55°C to +125°C
Output Voltage Low
0.05 100 100 100 f = 0.1 Hz to 10 Hz
RL = 100 kΩ to ground RL = 10 kΩ to ground RL = 100 kΩ to 3 V RL = 10 kΩ to 3 V
Short-Circuit Current BOTH AMPLIFIERS Power Supply Quiescent Current Quiescent Current (Shutdown)
2.9 2.8
3.5 0.01
Rev. 0 | Page 6 of 20
100 200
0.7
5 0.01 250
TA = −55°C to +125°C
Unit
2.7 2.5
2.3 60 20
Input Offset Current Input Voltage Range Open-Loop Gain Common-Mode Rejection Ratio Power Supply Rejection Ratio Voltage Noise Density Voltage Noise Dynamic Performance Gain Bandwidth Product Slew Rate Output Characteristics Output Voltage High
Max
100 200
4.5 1
mA μA
AD8231-EP ABSOLUTE MAXIMUM RATINGS THERMAL RESISTANCE
Table 4. Parameter Supply Voltage Output Short-Circuit Current Input Voltage (Common-Mode) Differential Input Voltage Storage Temperature Range Operational Temperature Range Package Glass Transition Temperature ESD (Human Body Model) ESD (Charged Device Model) ESD (Machine Model)
Rating 6V Indefinite1 −VS − 0.3 V to +VS + 0.3 V −VS − 0.3 V to +VS + 0.3 V –65°C to +150°C –55°C to +125°C 130°C 1.5 kV 1.5 kV 0.2 kV
1
For junction temperatures between 105°C and 130°C, short-circuit operation beyond 1000 hours can impact part reliability.
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.
Table 5. Thermal Pad Soldered to Board Not Soldered to Board
θJA 54 96
Unit °C/W °C/W
The θJA values in Table 5 assume a 4-layer JEDEC standard board. If the thermal pad is soldered to the board, it is also assumed it is connected to a plane. θJC at the exposed pad is 6.3°C/W.
MAXIMUM POWER DISSIPATION The maximum safe power dissipation for the AD8231-EP is limited by the associated rise in junction temperature (TJ) on the die. At approximately 130°C, which is the glass transition temperature, the plastic changes its properties. Even temporarily exceeding this temperature limit may change the stresses that the package exerts on the die, permanently shifting the parametric performance of the amplifiers. Exceeding a temperature of 130°C for an extended period can result in a loss of functionality.
ESD CAUTION
Rev. 0 | Page 7 of 20
AD8231-EP
12 +VS 11 –VS 10 OUTA (IN-AMP OUT) 9 REF
14 A0
NOTES 1. NC = NO CONNECT. DO NOT CONNECT TO THIS PIN. 2. THE EXPOSED PAD CAN BE CONNECTED TO THE NEGATIVE SUPPLY (–VS) OR LEFT FLOATING.
09707-002
OUTB (OP AMP OUT) 8
–INB 7
TOP VIEW (Not to Scale)
SDN 5
NC 4
AD8231-EP
+INB 6
+INA (IN-AMP +IN) 3
13 CS
PIN 1 INDICATOR
NC 1 –INA (IN-AMP –IN) 2
15 A1
16 A2
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
Figure 2. Pin Configuration
Table 6. Pin Function Descriptions Pin Number 1 2 3 4 5 6 7 8 9
Mnemonic NC −INA (IN-AMP −IN) +INA (IN-AMP +IN) NC SDN +INB −INB OUTB (OP AMP OUT) REF
10 11 12 13 14 15 16
OUTA (IN-AMP OUT) −VS +VS CS A0 A1 A2 EPAD
Description No Connect. Do not connect to this pin. Instrumentation Amplifier Negative Input. Instrumentation Amplifier Positive Input. No Connect. Do not connect to this pin. Shutdown. Operational Amplifier Positive Input. Operational Amplifier Negative Input. Operational Amplifier Output. Instrumentation Amplifier Reference Pin. It should be driven with a low impedance. Output is referred to this pin. Instrumentation Amplifier Output. Negative Power Supply. Connect to ground in single-supply applications. Positive Power Supply. Chip Select. Enables digital logic interface. Gain Setting Bit (LSB). Gain Setting Bit. Gain Setting Bit (MSB). Exposed Pad. Can be connected to the negative supply (−VS) or left floating.
Rev. 0 | Page 8 of 20
AD8231-EP TYPICAL PERFORMANCE CHARACTERISTICS INSTRUMENTATION AMPLIFIER PERFORMANCE CURVES 1000
1400
N: 5956 MEAN: 0.977167 SD: 11.8177
N: 5956 MEAN: –48.0779 1200 SD: 21.0433
800 1000 600
HITS
HITS
800
400
600 400
200
–60
–40
–20
0
20
40
60
80
100
CMRR (µV/V)
0 –500 –400 –300 –200 –100
Figure 3. Instrumentation Amplifier CMR Distribution, G = 1
200
300
400
500
1400
N: 5956 MEAN: 2.06788 700 SD: 1.07546
1200
INPUT OFFSET (nV)
600 500 HITS
100
Figure 6. Instrumentation Amplifier Gain Distribution, G = 1
800
400 300 200
1000 800 600 400 200
100
–10
–5
0
5
10
15
VOSI (µV)
0 –55 –45 –35 –25 –15 –5
09707-101
0 –15
0
GAIN ERROR (µV/V)
5
15
25
35
45
55
65
75
TEMPERATURE (°C)
09707-207
–80
09707-100
0 –100
09707-103
200
Figure 7. Instrumentation Amplifier Input Offset Voltage Drift, −55°C to +125°C
Figure 4. Instrumentation Amplifier Input Offset Voltage Distribution
20
800
N: 5956 MEAN: 10.3901 700 SD: 3.9553
15 OUTPUT OFFSET (µV)
600
HITS
500 400 300
10
5
0
200
–20
–10
0 VOSO (µV)
10
20
30
–10 –55 –45 –35 –25 –15 –5
09707-102
0 –30
Figure 5. Instrumentation Amplifier Output Offset Voltage Distribution
5
15
25
TEMPERATURE (°C)
35
45
55
65
75
09707-208
–5
100
Figure 8. Instrumentation Amplifier Output Offset Drift, −55°C to +125°C
Rev. 0 | Page 9 of 20
AD8231-EP 6
VREF = MIDSUPPLY VCM = MIDSUPPLY
0V, 4.96V
1000
500
3V
0
5
4 5V SINGLE SUPPLY
0V, 2.96V
2
3V SINGLE SUPPLY 1
20
35
50
65
80
95
110 125
TEMPERATURE (°C)
0
09707-209
5
Figure 9. Instrumentation Amplifier Bias Current vs. Temperature
0
2
3
4
5
6
Figure 12. Instrumentation Amplifier Input Common-Mode Range vs. Output Voltage, VREF = 0 V 6
INPUT COMMON-MODE VOLTAGE (V)
1.5 1.0 0.5 0 –0.5 –1.0 +VS = +2.5V –VS = –2.5V VREF = 0V
–2.0 –2.5
–2.0
–1.5
–1.0
–0.5
0
0.5
1.0
1.5
2.0
2.5
VCM (V)
4 0.02V, 4.22V
5V SINGLE SUPPLY 1.5V, 2.96V
3 2 0.02V, 2.22V
4.98V, 3.22V
2.98V, 2.22V
4.98V, 1.78V
3V SINGLE SUPPLY 1
2.98V, 0.78V
0.02V, 0.78V
1.5V, 0.04V 0 0
09707-006
–1.5
1.5V, 4.96V
5
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
OUTPUT VOLTAGE (V)
09707-004
BIAS CURRENT (nA)
1
OUTPUT VOLTAGE (V)
2.0
Figure 13. Instrumentation Amplifier Input Common-Mode Range vs. Output Voltage, VREF = 1.5 V
Figure 10. Instrumentation Amplifier Bias Current vs. Common-Mode Voltage, 5 V
6
1.0 INPUT COMMON-MODE VOLTAGE (V)
0.8 0.6 0.4 0.2 0 –0.2 –0.4 –0.6 +VS = +1.5V –VS = –1.5V VREF = 0V
–0.8 –1.0 –1.5
–1.2
–0.9
–0.6
–0.3
0
0.3
0.6
0.9
1.2
VCM (V)
Figure 11. Instrumentation Amplifier Bias Current vs. Common-Mode Voltage, 3 V
1.5
2.5V, 4.96V
5
5V SINGLE SUPPLY 4 4.98V, 3.72V
0.02V, 3.72V 3 2.5V, 2.96V
2.98V, 2.72V
2 0.02V, 1.72V
3V SINGLE SUPPLY
0.02V, 1.28V
2.5V, 0.04V
4.98V,1.28V
1 2.98V, 0.28V
0 0
09707-007
BIAS CURRENT (nA)
2.92V, 1.5V
0V, 0.04V
5V –500 –55 –40 –25 –10
4.92V, 2.5V
3
0.5
1.0
1.5
2.0
2.5
3.0
3.5
OUTPUT VOLTAGE (V)
4.0
4.5
5.0
09707-005
BIAS CURRENT (pA)
1500
09707-003
INPUT COMMON-MODE VOLTAGE (V)
2000
Figure 14. Instrumentation Amplifier Input Common-Mode Range vs. Output Voltage, VREF = 2.5 V
Rev. 0 | Page 10 of 20
AD8231-EP 50 40
15
G = 64 G = 32
30
5
G=8 CMRR (µV/V)
G=4 10
G=2 G=1
0
G=1
10
G = 16
20
–10
G=8
G = 128
0 –5 –10 –15
–20
–20
–30
–25
1k
10k
100k
1M
10M
FREQUENCY (Hz)
–30 –55 –40 –25 –10
09707-009
–40 100
5
20
35
50
65
80
95
Figure 18. Instrumentation Amplifier CMRR vs. Temperature
Figure 15. Instrumentation Amplifier Gain vs. Frequency
140
1000 800
G=1
120 G=8
600
POSITIVE PSRR (dB)
GAIN ERROR (µV/V)
900
200 0
G=1
–200 –400
110 125
TEMPERATURE (°C)
09707-218
GAIN (dB)
20
G = 128
G = 128
100 G = 128 80 60 40
–600
20
5
20
35
50
65
80
95
110 125
TEMPERATURE (°C)
0
09707-216
–1000 –55 –40 –25 –10
1
10
100
Figure 16. Instrumentation Amplifier Gain Drift vs. Temperature
10k
100k
Figure 19. Instrumentation Amplifier Positive PSRR vs. Frequency
140
140 G = 128
G=1
120 120 NEGATIVE PSRR (dB)
G=8 G=8
100 G=1 80
100 80 G = 128 60 40
60
40 10
100
1k
10k
100k
FREQUENCY (Hz)
Figure 17. Instrumentation Amplifier CMRR vs. Frequency
0 1
10
100
1k
100k
100k
FREQUENCY (Hz)
Figure 20. Instrumentation Amplifier Negative PSRR vs. Frequency
Rev. 0 | Page 11 of 20
09707-147
20
09707-010
CMRR (dB)
1k
FREQUENCY (Hz)
09707-146
–800
AD8231-EP
G = +128, 0.4µV/DIV
09707-012
G = +1, 1µV/DIV
1s/DIV
10
1
0.1
0.01 1
10
100
1k
10k
100k
FREQUENCY (Hz)
Figure 21. Instrumentation Amplifier 0.1 Hz to 10 Hz Noise 100
09707-107
CURRENT NOISE (pA/ Hz)
100
Figure 24. Instrumentation Amplifier Current Noise Spectral Density
G = +1 G = +8 G = +128
90 80
NOISE (nV/ Hz)
70 60 50 40 30
10 1
10
100
1k
FREQUENCY (Hz)
Figure 22. Instrumentation Amplifier Voltage Noise Spectral Density vs. Frequency, 5 V, 1 Hz to 1000 Hz 1000
Figure 25. Instrumentation Amplifier Small Signal Pulse Response, G = 1, RL = 2 kΩ, CL = 500 pF
G = +1 G = +8 G = +128
900
5µs/DIV
09707-011
20mV/DIV
0
09707-013
20
300pF NO LOAD
500pF
800pF
800
NOISE (nV/ Hz)
700 600 500 400 300
100 1
10
100
1k
FREQUENCY (Hz)
10k
100k
4µs/DIV
09707-008
20mV/DIV
0
09707-014
200
Figure 23. Instrumentation Amplifier Voltage Noise Spectral Density vs. Frequency, 5 V, 1 Hz to 1 MHz
Figure 26. Instrumentation Amplifier Small Signal Pulse Response for Various Capacitive Loads, G = 1
Rev. 0 | Page 12 of 20
AD8231-EP G = +8
G = +32 G = +128
2V/DIV
10µs/DIV
0.001%/DIV
Figure 27. Instrumentation Amplifier Small Signal Pulse Response, G = 4, 16, and 128, RL = 2 kΩ, CL = 500 pF
100µs/DIV
09707-018
20mV/DIV
09707-015
17.6µs TO 0.01% 21.4µs TO 0.001%
Figure 30. Instrumentation Amplifier Large Signal Pulse Response, G = 128, VS = 5 V 25
20 SETTLING TIME (µs)
2V/DIV
3.95µs TO 0.01% 4µs TO 0.001%
0.001% 15 0.01% 10
0 1
10
100
1k
09707-019
10µs/DIV
1k
09707-020
0.001%/DIV
09707-016
5
GAIN (V/V)
Figure 28. Instrumentation Amplifier Large Signal Pulse Response, G = 1, VS = 5 V
Figure 31. Instrumentation Amplifier Settling Time vs. Gain for a 4 V p-p Step, VS = 5 V 25 0.001% 20 SETTLING TIME (µs)
2V/DIV
3.75µs TO 0.01% 3.8µs TO 0.001%
15 0.01% 10
0.001%/DIV
10µs/DIV
09707-017
5
0 1
10
100 GAIN (V/V)
Figure 29. Instrumentation Amplifier Large Signal Pulse Response, G = 8, VS = 5 V
Figure 32. Instrumentation Amplifier Settling Time vs. Gain for a 2 V p-p Step, VS = 3 V
Rev. 0 | Page 13 of 20
AD8231-EP –0.2 –0.4 –0.6 –0.8 –1.0 +1.0 +0.8 +0.6 +0.4 +0.2 –VS 0.1
+25°C –55°C 1
10
100
OUTPUT CURRENT (mA)
–0.2 –0.4 –0.6 –0.8 –1.0 +1.0 +0.8 +0.6 +0.4 +0.2 –VS 0.1
+25°C –55°C 1
10
100
OUTPUT CURRENT (mA)
Figure 34. Instrumentation Amplifier Output Voltage Swing vs. Output Current, VS = 5 V
Figure 33. Instrumentation Amplifier Output Voltage Swing vs. Output Current, VS = 3 V
Rev. 0 | Page 14 of 20
09707-234
OUTPUT VOLTAGE SWING REFERRED TO SUPPLY VOLTAGES (V)
+VS
09707-233
OUTPUT VOLTAGE SWING REFERRED TO SUPPLY VOLTAGES (V)
+VS
AD8231-EP
–100
60
–110
40
–120 76° PHASE MARGIN
20
–130
0
–140
800pF 1nF 1.5nF 20mV/DIV
1k
10k
100k
1M
–150 10M
FREQUENCY (Hz)
Figure 38. Operational Amplifier Small Signal Response for Various Capacitive Loads, VS = 3 V
60
–110
40
–120 72° PHASE MARGIN
20
–130
0
–140 RL = 10kΩ CL = 200pF
–20 10
100
1k
10k
100k
1M
–150 10M
FREQUENCY (Hz)
Figure 36. Operational Amplifier Open-Loop Gain and Phase vs. Frequency, VS = 3 V 800pF
1nF
OUTPUT VOLTAGE (0.5V/DIV)
–100
OPEN-LOOP PHASE SHIFT (Degrees)
80
1nF║2kΩ
1.5nF║2kΩ
TIME (5µs/DIV)
Figure 39. Operational Amplifier Large Signal Transient Response, VS = 5 V
NO LOAD
2nF
OUTPUT VOLTAGE (0.5V/DIV)
NO LOAD
1.5nF
20mV/DIV
NO LOAD
09707-022
–90
5µs/DIV
1nF║2kΩ
1.5nF║2kΩ
09707-023
OPEN-LOOP GAIN (dB)
Figure 35. Operational Amplifier Open-Loop Gain and Phase vs. Frequency, VS = 5 V 100
5µs/DIV
TIME (5µs/DIV)
Figure 37. Operational Amplifier Small Signal Response for Various Capacitive Loads, VS = 5 V
09707-026
RL = 10kΩ CL = 200pF –20 10 100
300pF
09707-024
80
NO LOAD
09707-025
–90 OPEN-LOOP PHASE SHIFT (Degrees)
100
09707-021
OPEN-LOOP GAIN (dB)
OPERATIONAL AMPLIFIER PERFORMANCE CURVES
Figure 40. Operational Amplifier Large Signal Transient Response, VS = 3 V
Rev. 0 | Page 15 of 20
AD8231-EP +VS
800 700 600 500 400 300 200
0 10
100
1k
10k
100k
FREQUENCY (Hz)
BIAS CURRENT (nA)
2.5 2.0 1.5 1.0 0.5
+0.6 +0.4 +0.2
5
20
35
50
65
80
95
110 125
TEMPERATURE (°C)
10
100
–0.2 –0.4 –0.6 –0.8 –1.0 +1.0 +0.8 +0.6 +0.4 +0.2
+25°C –55°C 1
10
100
Figure 45. Operational Amplifier Output Voltage Swing vs. Output Current, VS = 5 V
400
140
300
120
+PSRR
200
100
PSRR (dB)
100 VS = ±2.5V
–100 VS = ±1.5V
80 –PSRR 60 40
–200
20
–2
–1
0
1
2
3
VCM (V)
09707-109
–300 –400 –3
1
OUTPUT CURRENT (mA)
Figure 42. Operational Amplifier Bias Current vs. Temperature
0
+25°C –55°C
–VS 0.1
09707-242
0
BIAS CURRENT (pA)
+0.8
+VS
VS = ±2.5V VS = ±1.5V
–0.5 –55 –40 –25 –10
–1.0 +1.0
Figure 44. Operational Amplifier Output Voltage Swing vs. Output Current, VS = 3 V
OUTPUT VOLTAGE SWING REFERRED TO SUPPLY VOLTAGES (V)
3.0
–0.8
OUTPUT CURRENT (mA)
Figure 41. Operational Amplifier Voltage Spectral Noise Density vs. Frequency 3.5
–0.6
09707-245
1
–0.4
–VS 0.1
09707-141
100
–0.2
0 1
10
100
1k
10k
100k
FREQUENCY (Hz)
Figure 46. Operational Amplifier Power Supply Rejection Ratio
Figure 43. Operational Amplifier Bias Current vs. Common Mode
Rev. 0 | Page 16 of 20
09707-148
SPECTRAL NOISE DENSITY (nV/ Hz)
900
09707-244
OUTPUT VOLTAGE SWING REFERRED TO SUPPLY VOLTAGES (V)
1000
AD8231-EP 160
6
140 CHANNEL SEPARATION (dB)
7
5 4
+25°C
3
–55°C
2 1
G = 128
120
G=1
100 80 60 40
3.1
3.5
3.9
4.3
4.7
5.1
SUPPLY VOLTAGE (V)
5.5
5.9
0 10
SOURCE CHANNEL: OP AMP AT G = 1 100
1k
10k
FREQUENCY (Hz)
Figure 48. Channel Separation vs. Frequency
Figure 47. Supply Current vs. Supply Voltage
Rev. 0 | Page 17 of 20
100k
09707-149
0 2.7
G=8
20
09707-247
SUPPLY CURRENT (mA)
PERFORMANCE CURVES VALID FOR BOTH AMPLIFIERS
AD8231-EP OUTLINE DIMENSIONS 4.00 BSC SQ
3.75 BSC SQ
0.75 0.60 0.50
0.80 MAX 0.65 TYP
12° MAX 1.00 0.85 0.80
0.65 BSC
TOP VIEW
SEATING PLANE
16
13 12
9
PIN 1 INDICATOR 1
2.25 2.10 SQ 1.95
8
5
4
0.25 MIN 1.95 BSC
0.05 MAX 0.02 NOM 0.35 0.30 0.25
(BOTTOM VIEW)
0.20 REF
COPLANARITY 0.08
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-220-VGGC
072808-A
PIN 1 INDICATOR
0.60 MAX 0.60 MAX
Figure 49. 16-Lead Lead Frame Chip Scale Package [LFCSP_VQ] 4 mm × 4 mm Body, Very Thin Quad (CP-16-4) Dimensions shown in millimeters
ORDERING GUIDE Model 1 AD8231TCPZ-EP-R7 1
Temperature Range −55°C to +125°C
Package Description 16-Lead LFCSP_VQ, 7” Tape and Reel
Z = RoHS Compliant Part.
Rev. 0 | Page 18 of 20
Package Option CP-16-4
AD8231-EP NOTES
Rev. 0 | Page 19 of 20
AD8231-EP NOTES
©2011 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D09707-0-5/11(0)
Rev. 0 | Page 20 of 20
