Analog Devices Inc. AD5222BRZ100

Description
The AD5222 is a dual-channel, 128-position, digitally controlled variable resistor (VR) device. It performs the same electronic adjustment function as a potentiometer or variable resistor. The device contains two fixed resistors with wiper contacts that tap the fixed resistor value at a point determined by a digitally controlled up/down counter. The resistance between the wiper and either end point of the fixed resistor provides a constant resistance step size. The variable resistor offers a true adjustable value of resistance, between Terminal A and the wiper, or Terminal B and the wiper. The fixed A-to-B terminal resistance has a nominal temperature coefficient of -35 ppm/°C.
The chip select CS, count CLK, and U/D direction control inputs set the variable resistor position. The MODE determines whether both VRs are incremented together or independently. With MODE at logic zero, both wipers are incremented UP or DOWN without changing the relative settings between the wipers. In the independent MODE (Logic 1), only the VR determined by the DACSEL pin is changed.

Features
128-Position, 2-Channel Potentiometer Replacement
10 kΩ, 50 kΩ, 100 kΩ, 1 MΩ
Very Low Power: 40 μA Max
±2.7 V Dual Supply Operation or 2.7 V to 5.5 V Single Supply Operation
Increment/Decrement Count Control

Applications
Stereo Channel Audio Level Control
Mechanical Potentiometer Replacement
Remote Incremental Adjustment Applications
Instrumentation: Gain, Offset Adjustment
Programmable Voltage-to-Current Conversion
Line Impedance Matching