Low Gain Drift
Precision Instrumentation Amplifier
AD8228
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 ©2008 Analog Devices, Inc. All rights reserved.
FEATURES
Easy to use
Pin strappable gains of 10 and 100
Wide power supply range: ±2.3 V to ±18 V
DC specifications (B Grade, G = 10)
2 ppm/°C gain drift
0.02% gain error
50 μV maximum input offset voltage
0.8 μV/°C maximum input offset drift
0.6 nA maximum input bias current
100 dB CMRR
AC specifications
650 kHz, –3 dB bandwidth (G = 10)
2 V/μs slew rate
Low noise
8 nV/√Hz, @ 1 kHz (G = 100)
0.3 μV p-p from 0.1 Hz to 10 Hz (G = 100)
APPLICATIONS
Weigh scales
Industrial process controls
Bridge amplifiers
Precision data acquisition systems
Medical instrumentation
Strain gages
Transducer interfaces
GENERAL DESCRIPTION
The AD8228 is a high performance instrumentation amplifier
with very high gain accuracy. Because all gain setting resistors
are internal and laser trimmed, gain accuracy and gain drift
are better than can be achieved with typical instrumentation
amplifiers.
Low voltage offset, low offset drift, low gain drift, high gain
accuracy, and high CMRR make this part an excellent choice
in applications that demand the best dc performance possible,
such as bridge signal conditioning.
CONNECTION DIAGRAM
8
7
6
5
1
2
3
4
–IN
G1
G2
+V
S
V
OUT
REF
–V
S
IN
TOP VIEW
(Not to Scale)
AD8228
07035-001
Figure 1.
Table 1. Instrumentation Amplifiers by Category
General
Purpose
Zero
Drift
Military
Grade
Low
Power
High Speed
PGA
AD8220
1
AD8231
1
AD620 AD627
1
AD8250
AD8221 AD8553
1
AD621 AD623
1
AD8251
AD8222 AD8555
1
AD524 AD8253
AD8224
1
AD8556
1
AD526
AD8228 AD8557
1
AD624
1
Rail-to-rail output.
The AD8228 operates on both single and dual supplies. Because
the part can operate on supplies up to ±18 V, it is well suited for
applications where high common-mode input voltages are
encountered. The AD8228 is available in 8-lead MSOP and
SOIC packages.
Performance is specified over the entire industrial temperature
range of −40°C to +85°C for all grades. Furthermore, the AD8228
is operational from −40°C to +125°C. For a pin-compatible ampli-
fier with similar specifications, but with a gain range of 1 to 1000,
see the
AD8221.
