International Airport Industrial Park

•

Mailing Address: PO Box 11400

•

Tucson, AZ 85734

•

Street Address: 6730 S. Tucson Blvd.

•

Tucson, AZ 85706

Tel: (520) 746-1111

•

Twx: 910-952-1111

•

Cable: BBRCORP

•

Telex: 066-6491

•

FAX: (520) 889-1510

•

Immediate Product Info: (800) 548-6132

INA120

FEATURES

q LOW OFFSET VOLTAGE: 25

q LOW OFFSET VOLTAGE DRIFT:

0.25

q PIN-STRAPPED GAINS: 1, 10, 100, 1000

q LOW GAIN DRIFT: 30ppm/

at G = 100

q HIGH COMMON-MODE REJECTION:

106dB at 60Hz, G = 100

APPLICATIONS

q BRIDGE AMPLIFIER

q THERMOCOUPLE AMPLIFIER

q RTD SENSOR AMPLIFIER

q MEDICAL INSTRUMENTATION

q DATA ACQUISITION SYSTEM

q SWITCHED-GAIN AMPLIFIER

DESCRIPTION

The INA120 is a precision instrumentation amplifier

ideal for accurate signal acquisition. It combines pre-

cision, protected-input operational amplifiers, laser-

trimmed gain-setting resistors, and a high common-

mode rejection difference amplifier on a single chip.

Simple pin-strapped connections set precise gains of 1,

10, 100 or 1000. External resistors can be used to set

any gain from one to 5000. Gains can be digitally

selected with an external multiplexer. Gain-sense con-

nections on the INA120 maintain accuracy when using

multiplexer or gain-switching circuitry. Low power

dissipation and careful on-chip thermal management

reduce warm-up drift and assure excellent long-term

stability.

The INA120 is available in both plastic and ceramic

18-pin DIP packages, specified for the industrial tem-

perature range.

Precision

INSTRUMENTATION AMPLIFIER

+

–

A

1

–

+

A

2

+

–

A

3

2k

Ω

2k

Ω

400

Ω

44

Ω

43

67

12

217

1

18

16

13

15

14

5

8

9

10

11

Gain Sense 1

–In

Offset Adjust

A Out

1

V+

V–

V

O

Com

A Out

2

+In

Gain

Sense 2

Gain Set 2

Gain Set 1

RC

X1000

X100

X10

1k

Ω

1k

Ω

20k

Ω

20k

Ω

10k

Ω

10k

Ω

10k

Ω

10k

Ω

1k

Ω

1k

Ω

®

PDS-1071

Printed in U.S.A. March, 1992