Dual 10kΩ 256-tap digital pot with I²C control
The MAX5477ETE+ is a dual-channel digital potentiometer from Analog Devices, each channel offering 256 wiper tap positions across a 10kΩ end-to-end resistance. The Linear taper means the wiper resistance changes linearly with the digital code — the standard curve for volume control, signal attenuation, and trim-pot replacement in analog signal chains. Communication is over the I²C bus, with a Selectable Address feature that lets up to four devices share the same two-wire interface on a single board. The non-volatile memory stores the wiper position at power-down, so the pot returns to the last-set value on next power-up — no software re-initialization routine needed after a brownout.
Supply and temperature envelope
The 70ppm/°C temperature coefficient means the resistance drifts about 0.7Ω per °C on a 10kΩ element — negligible for most trim and bias applications, but worth noting if the pot sets a precision threshold in a -40°C to +85°C sweep. Wiper resistance is 325Ω typical, which adds a small offset in the bottom of the resistive divider.
Package and board integration
The ±25% tolerance on the end-to-end resistance is typical for digital pots — the absolute value varies part-to-part, but the ratiometric accuracy (the wiper-to-end ratio) is set by the 256-tap resolution and the internal resistor string matching, not the absolute resistance. For applications that need a precise absolute resistance, a trim step or a tighter-tolerance part is required.