Dual 5k digital pot with non-volatile wiper storage
The MCP4261T-502E/SL is a dual-channel digital potentiometer from Microchip's WiperLock series, each channel offering 257 taps across a 5k ohm resistance with a linear taper. The non-volatile memory retains the wiper position after power-down, so the device powers up at the last programmed setting without needing a software restore on each boot. Communication is over a standard SPI interface, which allows daisy-chaining multiple MCP4261 devices on a single bus for multi-channel systems.
Parametric fit and design considerations
With 257 taps, the step resolution is 5k / 256 ≈ 19.5 ohms per tap, giving 0.39% of full-scale per step. The ±20% tolerance on the total resistance means the absolute step size varies between parts, but the ratiometric accuracy between taps is consistent — important for applications like adjustable voltage dividers or sensor offset trimming where the ratio matters more than the absolute resistance. The typical wiper resistance is 75 ohms, which adds a small series resistance that is negligible in high-impedance loads but becomes significant when driving low-impedance inputs (e.g., below 10k). The temperature coefficient of 150 ppm/°C is moderate — for a 5k pot, that is about 0.75 ohms per degree C, acceptable for calibration loops that are trimmed at room temperature and see less than 50°C drift. The part is ROHS3 compliant, which satisfies the EU RoHS directive for lead-free soldering and material restrictions.
It is not a pin-compatible drop-in — the MCP4014 uses a different package (SOT-23-5) and a simpler control scheme, so a board spin is required. The MCP41010-E/P is a through-hole volatile alternative with 256 taps and SPI, but it is also single-channel and through-hole only.