Precision, Dual-Channel
Instrumentation Amplifier
AD8222
FEATURES
Two channels in small 4 mm × 4 mm LFCSP
Gain set with 1 resistor per amplifier (G = 1 to 10,000)
Low noise
8 nV/√Hz at 1 kHz
0.25 μV p-p (0.1 Hz to 10 Hz)
High accuracy dc performance (B grade)
60 μV maximum input offset voltage
0.3 μV/°C maximum input offset drift
1.0 nA maximum input bias current
126 dB minimum CMRR (G = 100)
Excellent ac performance
140 kHz bandwidth (G = 100)
13 μs settling time to 0.001%
Differential output option (single channel)
Fully specified
Adjustable common-mode output
Supply range: ±2.3 V to ±18 V
FUNCTIONAL BLOCK DIAGRAM
OUT1
OUT2
14
+V
S
16
15
–IN1
RG1
RG1
+IN1
AD8222
1
2
3
4
12
11
10
9
–V
S
13
–IN2
RG2
RG2
+IN2
5
6
7
8
05947-001
+V
S
REF1
Figure 1. 4 mm × 4 mm LFCSP
Table 1. Instrumentation Amplifiers by Category
General
Purpose
Zero
Drift
Military
Grade
Low
Power
High Speed
PGA
APPLICATIONS
Multichannel data acquisition for
ECG and medical instrumentation
Industrial process controls
Wheatstone bridge sensors
Differential drives for
High resolution input ADCs
Remote sensors
1
See
for the latest selection of instrumentation amplifiers.
GENERAL DESCRIPTION
The AD8222 is a dual-channel, high performance instrumentation
amplifier that requires only one external resistor per amplifier
to set gains of 1 to 10,000.
The AD8222 is the first dual-instrumentation amplifier in the
small 4 mm × 4mm LFCSP. It requires the same board area as a
typical single instrumentation amplifier. The smaller package
allows a 2× increase in channel density and a lower cost per
channel, all with no compromise in performance.
The AD8222 can also be configured as a single-channel, differen-
tial output instrumentation amplifier. Differential outputs provide
high noise immunity, which can be useful when the output
signal must travel through a noisy environment, such as with
remote sensors. The configuration can also be used to drive
differential input ADCs.
Rev. A
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
The AD8222 maintains a minimum CMRR of 80 dB to 4 kHz
for all grades at G = 1. High CMRR over frequency allows the
AD8222 to reject wideband interference and line harmonics,
greatly simplifying filter requirements. The AD8222 also has a
typical CMRR drift over temperature of just 0.07 μV/V/°C at G = 1.
The AD8222 operates on both single and dual supplies and only
requires 2.2 mA maximum supply current for both amplifiers.
It is specified over the industrial temperature range of −40°C to
+85°C and is fully RoHS compliant.
For a single-channel version, see the
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
Fax: 781.461.3113 ©2006–2010 Analog Devices, Inc. All rights reserved.
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S
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