AD8207:  Zero Drift, High Voltage, Bidirectional Difference Amplifier

The AD8207 is a single-supply difference amplifier ideal for amplifying small differential voltages in the presence of large common-mode voltage. The operating input common-mode voltage range extends from −4 V to +65 V with a 5 V supply. The AD8207 works with a single-supply voltage of 3.3 V to 5 V, and is ideally suited to withstand large input PWM common-mode voltages, typical in solenoid and motor control applications.

The AD8207 is available in an 8-lead SOIC package. Excellent dc performance over temperature keeps errors in the mea-surement loop to a minimum. Offset drift is typically less than 500 nV/°C, and gain drift is typically below 10 ppm/°C.

The AD8207 is ideal for bidirectional current sensing applications. It features two reference pins,V_REF1 and V_REF2, that allow the user to easily offset the output of the device to any voltage within the supply range. With V_REF1 attached to the V+ pin and V_REF2 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 output offsets are achieved by applying an external low impedance voltage to the V_REF1 and V_REF2 pins.

• High-side current sensing in
  Motor control
  Solenoid control
  Diesel-injection control
  Engine management
  Suspension control
  Vehicle dynamic control
  DC-to-dc converters