256-tap dual 100k pot in 14-TSSOP
The MAX5387NAUD+T is a dual 100 kΩ digital potentiometer with 256 wiper positions per channel, configured as a linear-taper potentiometer and controlled over an I2C interface.
Wiper resistance, tempco, and tolerance — what limits your precision budget
The wiper resistance is 250 Ω typical — this sets the minimum end-to-end resistance when the wiper is at the top terminal and adds a fixed offset in voltage-divider mode. Temperature coefficient is 35 ppm/°C typical, so a 100 kΩ resistance drifts about 3.5 Ω per °C — negligible for gain trimming but relevant if the pot sets a precision threshold across temperature. Tolerance is ±25 % — the absolute resistance of each channel can vary by up to 25 kΩ from nominal; the ratiometric accuracy (tap-to-tap linearity) is tighter and is what matters for divider applications.
Supply rails, memory type, and bus addressing
Memory type is volatile — the wiper position resets to mid-scale on power-up and is lost when the supply drops below the minimum operating voltage. The I2C interface supports a selectable address pin, allowing up to two devices on the same bus without an address conflict.