Active digipot for trim and calibration
The MCP4161-503E/P is a 50 kOhm digital potentiometer with 257 taps and a linear taper, meaning the wiper resistance changes uniformly with the digital code — no log or audio curve to account for in the divider ratio. The 257 taps give roughly 0.39% resolution per step, fine enough for trimming a reference voltage or setting a bias point in an analog signal chain. Non-volatile memory retains the wiper setting through power cycles — no re-initialization routine needed at boot. The SPI interface lets a microcontroller write the wiper position directly; the protocol is simple and common across most MCU families.
Package and temperature grade
The 8-pin PDIP package (0.300-inch row spacing) is through-hole — easy to hand-assemble or socket in prototyping and low-volume production. The wiper resistance is 75 ohms typical, which matters when driving a low-impedance load — the voltage drop across the wiper adds to the divider output error.
ROHS3 compliant — no restricted substances to manage in the BOM.