Intersil claims first precision low-voltage digitally controlled potentiometer

The ISL22317 is an excellent choice for designs that require specific current and resistor values such as test and measurement circuits, medical devices, backlight controls, or adjusting specific resistances in analog circuits. The patent-pending architecture of the ISL22317 allows it to track an external resistor within 10ppm/oC, improving overall system accuracy for temperatures up to 125oC.

The device reduces programming time and development costs by letting users select accurate pre-determined resistor values, and use calculated resistor values in schematics. In addition, it allows one to use the known value of one system to calibrate other systems. The device employs an easy-to-use I2C interface to program accurate resistor settings >1 million times in the integrated EEPROM memory. It also features a zero-compensated wiper resistance in rheostat mode. By negating wiper resistance, overall accuracy is improved, especially at the low tap positions where the ratio of wiper resistance to actual resistance is much higher. This enables users to do schematic calculations based on an actual 1 percent value, instead of competitive solutions that have >±20 percent tolerance of the resistor string in addition to wiper resistance error.