The DS1868 has two 256-position potentiometers, with wiper positions each set as 8-bit values. The potentiometers can be used independently or stacked for increased total resistance and number of taps. Communication takes place through a 3-wire serial port interface that drives an internal control logic unit. Multiple DS1868s can be linked or daisy-chained for control by a single processor.
The DS1868 +5-volt Dual Digital Potentiometer was designed for applications requiring extremely low current consumption and extremely low cost. Maximum standby current is 1µA. The DS1868 is based on DS1267 technology but operates from a single +5-volt or from dual ±3-volt supplies.
Digital potentiometers improve upon mechanical devices with processor control and programmability, greater reliability and accuracy, and packaging options that facilitate automatic assembly. They are used for signal control in modems and phones, battery charging and control circuitry, tuning and calibration, offset trimming of operational amplifiers, gain control, and power supply regulation.