Digital Pots Consume Little Power

Addressing power consumption and cost concerns, the quad CAT5241 and dual CAT5221 digital potentiometer ICs provide 64 wiper positions (6-bit resolution) with a linear taper. Control is via a 400-kHz, two-wire interface, with the components consuming 5 µW in standby at 5V maximum. Tap positions are stored in embedded EEPROM registers and may be automatically retrieved upon power up. Each pot is controlled from an independent 6-bit digital control register and its four associated EEPROM registers. The value in one of the nonvolatile registers is also recalled upon power up. Additionally, the chips include four device address pins, allowing up to 16 devices or a maximum of 64 potentiometers to share a common two-wire bus. Both devices are available in 20-lead SOIC packages with four resistance options: 2.5, 10, 50 and 100 kiloherz. Prices start at $1.19 each/10K. CATALYST SEMICONDUCTOR, Sunnyvale, CA. (408) 542-1080.