INDUSTRIAL VOLTAGE AMPLIFIER IC

AM401

analog microelectronics

March 2006

Analog Microelectronics GmbH

Telefon: +49 (0)6131/91 073 – 0

3/21

An der Fahrt 13, D – 55124 Mainz

Telefax: +49 (0)6131/91 073 – 30

Rev. 2.3

Internet: http://www.analogmicro.de

E–Mail: info@analogmicro.de

FEATURES

• Supply voltage range: 6...35V

• Wide operating temperature range:

–40°C...+85°C

• Adjustable voltage reference:

5 to 10V

• Additional current/voltage source

• Instrumentation amplifier input

CMVI: 1.5...Vcc-3V

• Operational amplifier input

Vin: 0...Vcc-5V

• Adjustable gain and offset

• Adjustable output voltage range:

0...Vcc-5V, e.g. 0.5...4.5V, 0...5/10V

• Individually configurable function

modules

• Protection against reverse polarity

• Output current limitation

• Short-circuit protection

• Protection against ESD

• RoHS compliant

GENERAL DESCRIPTION

AM401 and AM401P [2] are universal voltage

transmitters designed for differential bridge signal

conditioning. The two devices differ in their offset

and offset drift values. The ICs are modular and

their functional units individually accessible. Both

ICs consist of a high-precision instrumentation

amplifier for differential input signals and an

operational amplifier for input signals referenced

to ground. A robust reference voltage source

(adjustable between 5 and 10V) can be used to

power external components. An operational

amplifier stage whose gain is also adjustable acts

as an output. The devices also contain an

additional operational amplifier which can be used

as a current or voltage source. The IC is protected

against reverse polarity and has an integrated

output current limit. Standard industrial voltages

(e.g. 0–5/10V, 0.5–4.5V) can be easily generated

using transmitter ICs AM401 and AM401P.

BLOCK DIAGRAM

1

2

3

4

14

13

5

6

11

15

12

V

BG

CVREF

CVSET

IN+

IN_

GND

ZA OUTIA INOP

7

8

GAIN

VOUT

VCC

VREF

VSET

Voltage Reference

AM401

+

_

OP2

+

_OP1

+

_ IA

Figure 1: Block diagram of AM401 (individually configurable function)