The MAX5477EUD+T is a dual-channel, 256-tap digital potentiometer from Analog Devices with a linear taper and 10kΩ end-to-end resistance. It uses an I²C interface for wiper control, and the wiper position is stored in non-volatile memory so it holds its setting after power is cycled. Typical applications include volume control in audio gear, programmable voltage dividers, LCD bias adjustment, and sensor trimming in industrial or telecom equipment where the linear law is required.
Non-volatile memory means the wiper position is stored internally — no external EEPROM or microcontroller re-initialization routine needed after a power cycle. That saves a few lines of firmware and one I/O pin. The wiper resistance is 325Ω typical. That's the resistance between the wiper pin and the internal tap point. It adds a small offset in the voltage-divider ratio, especially at the end stops. Factor it into your divider calculations if you're working with low-impedance loads.