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AD8225

Precision Gain of 5

Instrumentation Amplifier

FEATURES

No External Components Required

Highly Stable, Factory Trimmed Gain of 5

Low Power, 1.2 mA Max Supply Current

Wide Power Supply Range ( 1.7 V to

18 V)

Single- and Dual-Supply Operation

Excellent Dynamic Performance

High CMRR

86 dB Min @ DC

80 dB Min to 10 kHz

Wide Bandwidth

900 kHz

4 V to 36 V Single Supply

High Slew Rate

5 V/ s Min

Outstanding DC Precision

Low Gain Drift

5 ppm/ C Max

Low Input Offset Voltage

150

V Max

Low Offset Drift

2

V/ C Max

Low Input Bias Current

1.2 nA Max

APPLICATIONS

Patient Monitors

Current Transmitters

Multiplexed Systems

4 to 20 mA Converters

Bridge Transducers

Sensor Signal Conditioning

FUNCTIONAL BLOCK DIAGRAM

8

7

6

5

1

2

3

4

NC = NO CONNECT

NC

–IN

+IN

NC

REF

AD8225

GENERAL DESCRIPTION

The AD8225 is an instrumentation amplifier with a fixed gain

of 5

, which sets new standards of performance. The superior

CMRR of the AD8225 enables rejection of high frequency

common-mode voltage (80 dB Min @ 10 kHz). As a result,

higher ambient levels of noise from utility lines, industrial

equipment, and other radiating sources are rejected. Extended

CMV range enables the AD8225 to extract low level differential

signals in the presence of high common-mode dc voltage levels

even at low supply voltages.

Ambient electrical noise from utility lines is present at 60 Hz

and harmonic frequencies. Power systems operating at 400 Hz

create high noise environments in aircraft instrument clusters.

Good CMRR performance over frequency is necessary if power

system generated noise is to be rejected. The dc to 10 kHz

FREQUENCY – Hz

140

1

100k

10

100

1k

10k

130

120

110

100

90

80

70

60

50

40

30

HIGH PERFORMANCE IN AMP

@ GAIN OF 5

AD8225

Figure 1. Typical CMRR vs. Frequency

CMRR performance of the AD8225 rejects noise from utility

systems, motors, and repair equipment on factory floors, switch-

ing power supplies, and medical equipment.

Low input bias currents combined with a high slew rate of 5 V/

µs

make the AD8225 ideally suited for multiplexed applications.

The AD8225 provides excellent dc precision, with maximum

input offset voltage of 150

µV and drift of 2 µV/°C. Gain drift is

5ppm/

°C or less.

Operating on either single or dual supplies, the fixed gain of 5

and wide input common-mode voltage range make the AD8225

well suited for patient monitoring applications.

The AD8225 is packaged in an 8-lead SOIC package and is

specified over the standard industrial temperature range, –40

°C

to +85

°C.