General Description

The MAX4194 is a variable-gain precision instrumentation amplifier that combines Rail-to-Rail® single-supply operation, outstanding precision specifications, and a high gain bandwidth. This amplifier is also offered in three fixed-gain versions: the MAX4195 (G = +1V/V), the MAX4196 (G = +10V/V), and the MAX4197 (G = +100V/V). The fixed-gain instrumentation amplifiers feature a shutdown function that reduces the quiescent current to 8µA. A traditional three operational amplifier configuration is used to achieve maximum DC precision.

The MAX4194–MAX4197 have rail-to-rail outputs and inputs that can swing to 200mV below the negative rail and to within 1.1V of the positive rail. All parts draw only 93µA and operate from a single +2.7V to +7.5V supply or from dual ±1.35V to ±3.75V supplies. These amplifiers are offered in 8-pin SO packages and are specified for the extended temperature range (-40°C to +85°C).

See the MAX4198/MAX4199 data sheet for single-supply, precision differential amplifiers.

Features

♦ +2.7V Single-Supply Operation

♦ Low Power Consumption

93µA Supply Current

8µA Shutdown Current

(MAX4195/MAX4196/MAX4197)

♦ High Common-Mode Rejection: 115dB (G = +10V/V)

♦ Input Common-Mode Range Extends 200mV Below GND

♦ Low 50µV Input Offset Voltage (G ≥ +100V/V)

♦ Low ±0.01 Gain Error (G = +1V/V)

♦ 250kHz -3dB Bandwidth (G = +1V/V, MAX4194)

♦ Rail-to-Rail Outputs

Applications

Medical Equipment

Thermocouple Amplifier

4–20mA Loop Transmitters

Data-Acquisition Systems

Battery-Powered/Portable Equipment

Transducer Interface

Bridge Amplifier