REV. A

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use, nor for any infringements of patents or other rights of third parties

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a

AD627

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.

Tel: 781/329-4700

World Wide Web Site: http://www.analog.com

Fax: 781/326-8703

© Analog Devices, Inc., 1999

Micropower, Single and Dual Supply

Rail-to-Rail Instrumentation Amplifier

FUNCTIONAL BLOCK DIAGRAM

8-Lead Plastic DIP (N) and SOIC (R)

8

7

6

5

1

2

3

4

–IN

+IN

OUTPUT

REF

AD627

FEATURES

Micropower, 85

A Max Supply Current

Wide Power Supply Range (+2.2 V to

18 V)

Easy to Use

Gain Set with One External Resistor

Gain Range 5 (No Resistor) to 1,000

Higher Performance than Discrete Designs

Rail-to-Rail Output Swing

High Accuracy DC Performance

0.10% Gain Accuracy (G = 5) (AD627A)

10 ppm Gain Drift (G = 5)

125

V Max Input Offset Voltage (AD627B)

200

V Max Input Offset Voltage (AD627A)

1

V/ C Max Input Offset Voltage Drift (AD627B)

3

V/ C Max Input Offset Voltage Drift (AD627A)

10 nA Max Input Bias Current

Noise: 38 nV/

√Hz RTI Noise @ 1 kHz (G = 100)

Excellent AC Specifications

77 dB Min CMRR (G = 5) (AD627A)

83 dB Min CMRR (G = 5) (AD627B)

80 kHz Bandwidth (G = 5)

135

s Settling Time to 0.01% (G = 5, 5 V Step)

APPLICATIONS

4 mA-to-20 mA Loop Powered Applications

Low Power Medical Instrumentation—ECG, EEG

Transducer Interfacing

Thermocouple Amplifiers

Industrial Process Controls

Low Power Data Acquisition

Portable Battery Powered Instruments

PRODUCT DESCRIPTION

The AD627 is an integrated, micropower, instrumentation

amplifier that delivers rail-to-rail output swing on single and

dual (+2.2 V to

±18 V) supplies. The AD627 provides the user

with excellent ac and dc specifications while operating at only

85

µA max.

The AD627 offers superior user flexibility by allowing the user

to set the gain of the device with a single external resistor, and

by conforming to the 8-lead industry standard pinout configura-

tion. With no external resistor, the AD627 is configured for a

gain of 5. With an external resistor, it can be programmed for

gains of up to 1000.

Wide supply voltage range (+2.2 V to

±18 V), and micropower

current consumption make the AD627 a perfect fit for a wide

range of applications. Single supply operation, low power con-

sumption and rail-to-rail output swing make the AD627 ideal

for battery powered applications. Its rail-to-rail output stage

maximizes dynamic range when operating from low supply

voltages. Dual supply operation (

±15 V) and low power con-

sumption make the AD627 ideal for industrial applications,

including 4 mA-to-20 mA loop-powered systems.

The AD627 does not compromise performance, unlike other

micropower instrumentation amplifiers. Low voltage offset,

offset drift, gain error, and gain drift keep dc errors to a mini-

mum in the users system. The AD627 also holds errors over

frequency to a minimum by providing excellent CMRR over

frequency. Line noise, as well as line harmonics, will be rejected,

since the CMRR remains high up to 200 Hz.

The AD627 provides superior performance, uses less circuit

board area and does it for a lower cost than micropower discrete

designs.

FREQUENCY – Hz

100

1

90

80

70

60

50

40

30

20

10

0

10

100

1k

10k

TRADITIONAL

LOW POWER

DISCRETE DESIGN

AD627

Figure 1. CMRR vs. Frequency,

±5 V