The DS1669 Dallastat is a digital rheostat or potentiometer. This device provides 64 possible uniform tap points over the entire resistive range. The standard resistive ranges are 10 k, 50 k, and 100 k. The Dallastat can be controlled by either a switch contact closure input or a digital source input such as a CPU. Wiper position is maintained in the absence of power through the use of a EEPROM memory cell array. The EEPROM cell array will withstand more than 50,000 writes.

The DS1669 is offered in two standard IC packages which include an 8-pin 300-mil DIP and an 8-pin 208-mil SOIC. The DS1669 can be configured to operate using a single pushbutton, dual pushbutton or digital source input by varying power-on conditions. This is illustrated in Figures 1 and 2. The DS1669 pinouts allow access to both ends of the potentiometer RL, RH, and the wiper, RW. Control inputs include the digital source input, D, the up contact input, UC, and the down contact input, DC. Other pins include the positive, +V, and negative, -V, supply inputs. The DS1669 is specified to operate from -40°C to +85°C.