Precision Instrumentation Amplifier
AD8221-EP
Enhanced Product
FEATURES
TYPICAL CONNECTION DIAGRAM
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
APPLICATIONS
AD8221-EP
–IN 1
8
+VS
RG 2
7
VOUT
RG 3
6
REF
+IN 4
5
–VS
TOP VIEW
03149-001
Specified from −55°C to +125°C
0.9 μV/°C maximum input offset average TC
10 ppm/°C maximum gain vs. temperature (G = 1)
Excellent ac specifications
80 dB minimum CMRR at 10 kHz (G = 1)
–3 dB bandwidth: 825 kHz typical (G = 1)
2 V/μs typical slew rate
Low noise
8 nV/√Hz, at 1 kHz, maximum input voltage noise
0.25 μV p-p RTI (G = 100 to 1000)
High accuracy dc performance
80 dB minimum CMRR DC to 60 Hz (G = 1)
70 μV maximum input offset voltage
2 nA maximum input bias current
Wide power supply range: ±2.3 V to ±18 V
Available in space-saving MSOP
Gain set with 1 external resistor (gain range 1 to 1000)
Figure 1.
GENERAL DESCRIPTION
The AD8221-EP is a gain programmable, high performance
instrumentation amplifier that delivers the industry’s highest
CMRR over frequency in its class. The CMRR of instrumentation
amplifiers on the market today falls off at 200 Hz. In contrast, the
AD8221-EP maintains a minimum CMRR of 80 dB to 10 kHz at
G = 1. High CMRR over frequency allows the AD8221-EP to
reject wideband interference and line harmonics, greatly
simplifying filter requirements.
Possible applications include precision data acquisition, biomedical
analysis, and aerospace instrumentation.
Low voltage offset, low offset drift, low gain drift, high gain
accuracy, and high CMRR make this device an excellent choice
in applications that demand the best dc performance possible, such
as bridge signal conditioning.
Programmable gain affords the user design flexibility. A single
resistor sets the gain from 1 to 1000. The AD8221-EP operates
on both single and dual supplies and is well suited for applications
where ±10 V input voltages are encountered.
The AD8221-EP is specified over the −55°C to +125°C military
temperature range. It is available in an 8-lead MSOP package.
Bridge amplifiers
Precision data acquisition systems
Strain gages
Transducer interfaces
Additional application and technical information can be found
in the AD8221 data sheet.
120
110
AD8221-EP
CMRR (dB)
100
90
COMPETITOR 1
80
70
60
COMPETITOR 2
50
10
100
1k
10k
FREQUENCY (Hz)
100k
13702-002
40
Figure 2. Typical CMRR vs. Frequency for G = 1
Rev. 0
Document Feedback
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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
©2016 Analog Devices, Inc. All rights reserved.
Technical Support
www.analog.com
AD8221-EP
Enhanced Product
TABLE OF CONTENTS
Features .............................................................................................. 1 Thermal Characteristics ...............................................................5 Enhanced Product Features ............................................................ 1 ESD Caution...................................................................................5 Applications ....................................................................................... 1 Pin Configuration and Function Descriptions..............................6 Typical Connection Diagram .......................................................... 1 Typical Performance Characteristics ..............................................7 General Description ......................................................................... 1 Outline Dimensions ....................................................................... 14 Revision History ............................................................................... 2 Ordering Guide .......................................................................... 14 Specifications..................................................................................... 3 Absolute Maximum Ratings............................................................ 5 REVISION HISTORY
4/16—Revision 0: Initial Version
Rev. 0 | Page 2 of 14
Enhanced Product
AD8221-EP
SPECIFICATIONS
VS = ±15 V, VREF = 0 V, TA = 25°C, G = 1, RL = 2 kΩ, unless otherwise noted.
Table 1.
Parameter
COMMON-MODE REJECTION RATIO (CMRR)
CMRR DC to 60 Hz with 1 kΩ Source Imbalance
G=1
G = 10
G = 100
G = 1000
CMRR at 10 kHz
G=1
G = 10
G = 100
G = 1000
NOISE
Voltage Noise, 1 kHz
Input Voltage Noise, eNI
Output Voltage Noise, eNO
Referred to Input (RTI)
G=1
G = 10
G = 100 to 1000
Current Noise
VOLTAGE OFFSET1
Input Offset, VOSI
Over Temperature
Average Temperature Coefficient (TC)
Output Offset, VOSO
Over Temperature
Average TC
Offset RTI vs. Supply (PSR)
G=1
G = 10
G = 100
G = 1000
INPUT CURRENT
Input Bias Current
Over Temperature
Average TC
Input Offset Current
Over Temperature
Average TC
REFERENCE INPUT
RIN
IIN
Voltage Range
Gain to Output
Test Conditions/Comments
Min
Typ
Max
Unit
VCM = −10 V to +10 V
80
100
120
130
dB
dB
dB
dB
80
90
100
100
dB
dB
dB
dB
VCM = –10 V to +10 V
RTI noise = √eNI2 + (eNO/G)2
VIN+, VIN−, VREF = 0
8
75
nV/√Hz
nV/√Hz
f = 0.1 Hz to 10 Hz
2
0.5
0.25
40
6
f = 1 kHz
f = 0.1 Hz to 10 Hz
VS = ±5 V to ±15 V
TA = −55°C to +125°C
μV p-p
μV p-p
μV p-p
fA/√Hz
pA p-p
70
150
0.9
600
1.2
9
VS = ±5 V to ±15 V
TA = −55°C to +125°C
μV
μV
μV/°C
μV
mV
μV/°C
VS = ±2.3 V to ±18 V
90
100
120
120
100
120
140
140
0.5
TA = −55°C to +125°C
11
0.3
TA = −55°C to +125°C
dB
dB
dB
dB
2
3.75
1
2.25
7
20
50
VIN+, VIN−, VREF = 0
−VS
1 ± 0.0001
Rev. 0 | Page 3 of 14
60
+VS
nA
nA
pA/°C
nA
nA
pA/°C
kΩ
μA
V
V/V
AD8221-EP
Parameter
POWER SUPPLY
Operating Range
Quiescent Current
Over Temperature
DYNAMIC RESPONSE
Small Signal −3 dB Bandwidth
G=1
G = 10
G = 100
G = 1000
Settling Time 0.01%
G = 1 to 100
G = 1000
Settling Time 0.001%
G = 1 to 100
G = 1000
Slew Rate
GAIN
Gain Range
Gain Error
G=1
G = 10
G = 100
G = 1000
Gain Nonlinearity
G = 1 to 10
G = 100
G = 1000
G = 1 to 100
Gain vs. Temperature
G=1
G > 12
INPUT
Input Impedance
Differential
Common Mode
Input Operating Voltage Range3
Over Temperature
Input Operating Voltage Range
Over Temperature
OUTPUT
Output Swing
Over Temperature
Output Swing
Over Temperature
Short-Circuit Current
TEMPERATURE RANGE
Specified Performance
Enhanced Product
Test Conditions/Comments
Min
VS = ±2.3 V to ±18 V
±2.3
TA = −55°C to +125°C
Typ
Max
Unit
0.9
1
±18
1
1.2
V
mA
mA
825
562
100
14.7
kHz
kHz
kHz
kHz
10
80
μs
μs
13
110
2
2.5
μs
μs
V/μs
V/μs
10 V step
10 V step
G=1
G = 5 to 100
G = 1 + (49.4 kΩ/RG)
1.5
2
1
1000
V/V
0.1
0.3
0.3
0.3
%
%
%
%
5
7
10
15
15
20
50
100
ppm
ppm
ppm
ppm
3
10
–50
ppm/°C
ppm/°C
–VS + 1.9
–VS + 2.0
–VS + 1.9
–VS + 2.0
+VS − 1.1
+VS − 1.2
+VS − 1.2
+VS − 1.3
GΩ||pF
GΩ||pF
V
V
V
V
–VS + 1.1
–VS + 1.4
–VS + 1.2
–VS + 1.6
+VS − 1.2
+VS − 1.3
+VS − 1.4
+VS − 1.5
V
V
V
V
mA
+125
°C
VOUT ± 10 V
VOUT = −10 V to +10 V
RL = 10 kΩ
RL = 10 kΩ
RL = 10 kΩ
RL = 2 kΩ
100||2
100||2
VS = ±2.3 V to ±5 V
TA = −55°C to +125°C
VS = ±5 V to ±18 V
TA = −55°C to +125°C
RL = 10 kΩ
VS = ±2.3 V to ±5 V
TA = −55°C to +125°C
VS = ±5 V to ±18 V
TA = −55°C to +125°C
18
−55
1
Total RTI VOS = (VOSI) + (VOSO/G).
Does not include the effects of external resistor RG.
3
One input grounded. G = 1.
2
Rev. 0 | Page 4 of 14
Enhanced Product
AD8221-EP
ABSOLUTE MAXIMUM RATINGS
THERMAL CHARACTERISTICS
Table 2.
Parameter
Supply Voltage
Internal Power Dissipation
Output Short-Circuit Current
Input Voltage (Common-Mode)
Differential Input Voltage
Storage Temperature Range
Operating Temperature Range
Specification for a device in free air.
Rating
±18 V
200 mW
Indefinite
±VS
±VS
−65°C to +150°C
−55°C to +125°C
Table 3.
Package
8-Lead MSOP, 4-Layer JEDEC Board
ESD CAUTION
Stresses at or above those listed under Absolute Maximum
Ratings may cause permanent damage to the product. This is a
stress rating only; functional operation of the product at these
or any other conditions above those indicated in the operational
section of this specification is not implied. Operation beyond
the maximum operating conditions for extended periods may
affect product reliability.
Rev. 0 | Page 5 of 14
θJA
135
Unit
°C/W
AD8221-EP
Enhanced Product
AD8221-EP
–IN
1
8
+VS
RG
2
7
VOUT
RG
3
6
REF
+IN
4
5
–VS
TOP VIEW
(Not to Scale)
13702-103
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
Figure 3. Pin Configuration
Table 4. Pin Function Descriptions
Pin No.
1
2, 3
4
5
6
7
8
Mnemonic
−IN
RG
+IN
−VS
REF
VOUT
+VS
Description
Negative Input Terminal.
Gain Setting Terminal. Place resistor across the RG pins to set the gain. G = 1 + (49.4 kΩ/RG).
Positive Input Terminal.
Negative Power Supply Terminal.
Reference Voltage Terminal. Drive this terminal with a low impedance voltage source to level-shift the output.
Output Terminal.
Positive Power Supply Terminal.
Rev. 0 | Page 6 of 14
Enhanced Product
AD8221-EP
TYPICAL PERFORMANCE CHARACTERISTICS
T = 25°C, VS = ±15 V, RL = 10 kΩ, unless otherwise noted.
1600
3500
1400
3000
1200
2500
UNITS
UNITS
1000
800
2000
1500
600
1000
400
–100
–50
0
50
100
150
CMR (µV/V)
0
–0.9
13702-003
0
–150
–0.3
0
0.3
0.6
0.9
INPUT OFFSET CURRENT (nA)
Figure 7. Typical Distribution of Input Offset Current
Figure 4. Typical Distribution for CMR (G = 1)
15
INPUT COMMON-MODE VOLTAGE (V)
2100
1800
1500
1200
900
600
300
–40
–20
0
20
40
60
INPUT OFFSET VOLTAGE (µV)
VS = ±15V
5
0
VS = ±5V
–5
–10
–15
–15
13702-004
0
–60
10
–10
–5
0
5
10
15
OUTPUT VOLTAGE (V)
13702-007
2400
UNITS
–0.6
13702-006
500
200
Figure 8. Input Common-Mode Voltage vs. Output Voltage, G = 1
Figure 5. Typical Distribution of Input Offset Voltage
15
INPUT COMMON-MODE VOLTAGE (V)
3000
2500
1500
1000
VS = ±15V
5
0
VS = ±5V
–5
–10
0
–1.5
–15
–15
–1.0
–0.5
0
0.5
1.0
INPUT BIAS CURRENT (nA)
1.5
Figure 6. Typical Distribution of Input Bias Current
Rev. 0 | Page 7 of 14
–10
–5
0
5
OUTPUT VOLTAGE (V)
10
15
13702-008
500
13702-005
UNITS
2000
10
Figure 9. Input Common-Mode Voltage vs. Output Voltage, G = 100
AD8221-EP
Enhanced Product
0.80
180
0.75
160
0.70
140
0.60
VS = ±5V
0.55
120
GAIN = 10
100
GAIN = 1
60
0.45
40
–10
–5
0
5
10
15
COMMON-MODE VOLTAGE (V)
20
0.1
1
100
1k
10k
100k
1M
Figure 13. Positive PSRR vs. Frequency, RTI (G = 1 to 1000)
2.00
180
1.75
160
1.50
140
1.25
1.00
0.75
GAIN = 100
120
GAIN = 10
100
GAIN = 1
80
0.50
60
0.25
40
0
0.01
0.1
1
10
WARM-UP TIME (min)
20
0.1
100
1k
10k
100k
1M
Figure 14. Negative PSRR vs. Frequency, RTI (G = 1 to 1000)
5
70
VS = ±15V
GAIN = 1000
60
3
50
2
40
INPUT BIAS CURRENT
–1
20
10
–2
0
–3
–10
–4
–20
5
20
35
50
65
TEMPERATURE (°C)
80
95
110 125
GAIN = 1
–30
100
13702-011
–5
–55 –40 –25 –10
GAIN = 10
1k
10k
100k
1M
FREQUENCY (Hz)
Figure 12. Input Offset Current and Input Bias Current vs. Temperature
Rev. 0 | Page 8 of 14
Figure 15. Gain vs. Frequency
10M
13702-015
INPUT OFFSET CURRENT
GAIN = 100
30
GAIN (dB)
1
0
10
FREQUENCY (Hz)
Figure 11. Change in Input Offset Voltage vs. Warm-Up Time
4
1
13702-013
NEGATIVE PSRR (dB)
GAIN = 1000
13702-010
CHANGE IN INPUT OFFSET VOLTAGE (µV)
10
FREQUENCY (Hz)
Figure 10. Input Bias Current (IBIAS) vs. Common-Mode Voltage (CMV)
INPUT CURRENT (nA)
GAIN = 1000
80
0.50
0.40
–15
GAIN = 100
13702-012
POSITIVE PSRR (dB)
VS = ±15V
0.65
13702-009
INPUT BIAS CURRENT (nA)
GAIN = 1000
Enhanced Product
160
INPUT VOLTAGE LIMIT (V)
REFERRED TO SUPPLY VOLTAGES
–0.4
GAIN = 100
120
GAIN = 10
100
–0
+VS
GAIN = 1000
140
CMRR (dB)
AD8221-EP
GAIN = 1
80
60
–0.8
–1.2
–1.6
–2.0
–2.4
+2.4
+2.0
+1.6
+1.2
+0.8
+0.4
10
100
1k
10k
100k
1M
FREQUENCY (Hz)
+0
–0.4
GAIN = 100
–0.8
100
GAIN = 1
OUTPUT VOLTAGE SWING (V)
REFERRED TO SUPPLY VOLTAGES
GAIN = 1000
GAIN = 10
80
60
15
RL = 10kΩ
–1.2
RL = 2kΩ
–1.6
–2.0
+2.0
+1.6
RL = 2kΩ
+1.2
+0.8
RL = 10kΩ
+0.4
–VS
1
10
100
1k
10k
100k
1M
FREQUENCY (Hz)
+0
13702-017
40
0.1
20
–0
+VS
120
10
Figure 19. Input Voltage Limit vs. Supply Voltage, G = 1
160
CMRR (dB)
5
SUPPLY VOLTAGE ( ±V)
Figure 16. CMRR vs. Frequency, RTI
140
0
0
5
10
15
20
SUPPLY VOLTAGE (±V)
13702-020
1
13702-019
–VS
13702-016
40
0.1
Figure 20. Output Voltage Swing vs. Supply Voltage, G = 1
Figure 17. CMRR vs. Frequency, RTI, 1 kΩ Source Imbalance
30
100
VS = ±15V
OUTPUT VOLTAGE SWING (V p-p)
80
60
20
0
–20
–40
–60
20
10
0
5
20
35
50
65
80
TEMPERATURE (°C)
95
110 125
1
10
100
1k
10k
LOAD RESISTANCE (Ω)
Figure 21. Output Voltage Swing vs. Load Resistance
Figure 18. CMR vs. Temperature
Rev. 0 | Page 9 of 14
13702-021
–80
–100
–55 –40 –25 –10
13702-018
CMR (µV/V)
40
AD8221-EP
Enhanced Product
+VS –0
VS = ±15V
OUTPUT VOLTAGE SWING (V)
REFERRED TO SUPPLY VOLTAGES
–1
SOURCING
ERROR (100ppm/DIV)
–2
–3
+3
+2
SINKING
1
2
3
4
5
6
7
8
9
10
11
12
OUTPUT CURRENT (mA)
–10
Figure 22. Output Voltage Swing vs. Output Current, G = 1
–6
–4
–2
0
2
4
OUTPUT VOLTAGE (V)
6
8
10
Figure 23. Gain Nonlinearity, G = 1, RL = 10 kΩ
VOLTAGE NOISE SPECTRAL DENSITY RTI (nV/√Hz)
13702-023
ERROR (1ppm/DIV)
–8
–6
–4
–2
0
2
4
OUTPUT VOLTAGE (V)
6
8
10
Figure 25. Gain Nonlinearity, G = 1000, RL = 10 kΩ
VS = ±15V
–10
–8
1k
GAIN = 1
100
GAIN = 10
GAIN = 100
10
GAIN = 1000
GAIN = 1000
BW LIMIT
1
1
10
100
1k
10k
100k
FREQUENCY (Hz)
13702-026
0
13702-022
–VS +0
13702-025
+1
Figure 26. Voltage Noise Spectral Density vs. Frequency (G = 1 to 1000)
–8
–6
–4
–2
0
2
4
OUTPUT VOLTAGE (V)
6
8
10
2µV/DIV
1s/DIV
Figure 27. 0.1 Hz to 10 Hz RTI Voltage Noise (G = 1)
Figure 24. Gain Nonlinearity, G = 100, RL = 10 kΩ
Rev. 0 | Page 10 of 14
13702-027
–10
13702-024
ERROR (10ppm/DIV)
VS = ±15V
Enhanced Product
AD8221-EP
30
VS = ±15V
OUTPUT VOLTAGE (V p-p)
25
20
GAIN = 1
GAIN = 10, 100, 1000
15
10
1s/DIV
0
1k
10k
100k
13702-031
0.1µV/DIV
13702-028
5
1M
FREQUENCY (Hz)
Figure 31. Large Signal Frequency Response
1k
5V/DIV
100
1
10
100
1k
10k
FREQUENCY (Hz)
Figure 29. Current Noise Spectral Density vs. Frequency
20µs/DIV
13702-032
10
7.9µs TO 0.01%
8.5µs TO 0.001%
13702-029
0.002%/DIV
Figure 32. Large Signal Pulse Response and Settling Time (G = 1), 0.002%/DIV
5V/DIV
5pA/DIV
1s/DIV
Figure 30. 0.1 Hz to 10 Hz Current Noise
4.9µs TO 0.01%
5.6µs TO 0.001%
20µs/DIV
Figure 33. Large Signal Pulse Response and Settling Time (G = 10),
0.002%/DIV
Rev. 0 | Page 11 of 14
13702-033
0.002%/DIV
13702-030
CURRENT NOISE SPECTRAL DENSITY RTI (fA/√Hz)
Figure 28. 0.1 Hz to 10 Hz RTI Voltage Noise (G = 1000)
AD8221-EP
Enhanced Product
5V/DIV
0.002%/DIV
10.3µs TO 0.01%
13.4µs TO 0.001%
20µs/DIV
Figure 34. Large Signal Pulse Response and Settling Time (G = 100),
0.002%/DIV
4µs/DIV
13702-037
13702-034
20mV/DIV
Figure 37. Small Signal Response, G = 10, RL = 2 kΩ, CL = 100 pF
5V/DIV
0.002%/DIV
83µs TO 0.01%
112µs TO 0.001%
10µs/DIV
Figure 35. Large Signal Pulse Response and Settling Time (G = 1000),
0.002%/DIV
13702-038
200µs/DIV
13702-035
20mV/DIV
Figure 38. Small Signal Response, G = 100, RL = 2 kΩ, CL = 100 pF
13702-036
4µs/DIV
100µs/DIV
13702-039
20mV/DIV
20mV/DIV
Figure 39. Small Signal Response, G = 1000, RL = 2 kΩ, CL = 100 pF
Figure 36. Small Signal Response, G = 1, RL = 2 kΩ, CL = 100 pF
Rev. 0 | Page 12 of 14
Enhanced Product
AD8221-EP
1000
SETTLING TIME (µs)
10
SETTLED TO 0.001%
SETTLED TO 0.01%
5
100
SETTLED TO 0.001%
10
0
0
5
10
15
20
OUTPUT VOLTAGE STEP SIZE (V)
Figure 40. Settling Time vs. Output Voltage Step Size (G = 1)
1
1
10
100
GAIN
Figure 41. Settling Time vs. Gain for a 10 V Step
Rev. 0 | Page 13 of 14
1000
13702-041
SETTLED TO 0.01%
13702-040
SETTLING TIME (µs)
15
AD8221-EP
Enhanced Product
OUTLINE DIMENSIONS
3.20
3.00
2.80
8
3.20
3.00
2.80
5.15
4.90
4.65
5
1
4
PIN 1
IDENTIFIER
0.65 BSC
0.95
0.85
0.75
15° MAX
1.10 MAX
0.40
0.25
6°
0°
0.23
0.09
0.80
0.55
0.40
COMPLIANT TO JEDEC STANDARDS MO-187-AA
10-07-2009-B
0.15
0.05
COPLANARITY
0.10
Figure 42. 8-Lead Mini Small Outline Package [MSOP]
(RM-8)
Dimensions shown in millimeters
ORDERING GUIDE
Model1
AD8221TRMZ-EP
AD8221TRMZ-EP-R7
1
Temperature Range
–55°C to +125°C
–55°C to +125°C
Package Description
8-Lead Mini Small Outline Package [MSOP]
8-Lead Mini Small Outline Package [MSOP]
Z = RoHS Compliant Part.
©2016 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D13702-0-4/16(0)
Rev. 0 | Page 14 of 14
Package Option
RM-8
RM-8
Branding
Y67
Y67