Single Supply 42 V System Difference Amplifier

The AD8205 is a single-supply difference amplifier for amplify-ing small differential voltages in the presence of large common-mode voltages. The operating input common-mode voltage range extends from −2 V to +65 V. The typical single-supply voltage is 5 V.

The AD8205 is offered in an 8-lead SOIC package and rated for operation from −40°C to +125°C for the Y and W grade models. The H grade version of the AD8205 is rated from −40°C to +150°C.

Excellent dc performance over temperature keeps errors in the measurement loop to a minimum. Offset drift is typically less than 15 μV/°C, and gain drift is typically below 30 ppm/°C.

The output offset can be adjusted from 0.05 V to 4.8 V with a 5 V supply by using the VREF1 and VREF2 pins. With VREF1 attached to the V+ pin, and VREF2 attached to the GND pin, the output is set at half scale. Attaching both pins to GND causes the output to be unipolar, starting near ground. Attaching both pins to V+ causes the output to be unipolar starting near V+. Other offsets can be obtained by applying an external voltage to the VREF1 and VREF2 pins.

Applications

High-side current sensing in:

* Motor controls

* Transmission controls

* Diesel injection controls

* Engine management

* Suspension controls

* Vehicle dynamic controls

* DC-to-dc converters

* Ideal for current shunt applications

* High Common-mode voltage range

−2 V to +65 V operating

−25 V to +75 V survival

* Gain = 50 V/V

* Wide operating temperature range

−40°C to +125°C: Y and W grade

−40°C to +150°C: H grade

* Bidirectional operation

* Available in 8-Lead SOIC.

* EXCELLENT AC AND DC

PERFORMANCE

15 µV/°C offset drift

30 ppm/°C gain drift

80 dB CMRR dc to 20 kHz

* Qualified for Automotive Applications