[05]

Why is there level conversion though if the digipot (MCP4141) is 2.7V to 5.5V?

Personally I'd just use breadboard, it's just a 8 pin IC and a ESP module, for a one-off hack..

[announcer4614]

Hey, author here. There's a line in the digipot datasheet that says the voltage on the A/B/W pins must be within -0.3V to VDD + 0.3V. The fan's line for the wiper pin is 5V, which would fall well outside of that if I gave the digipot's VDD 3.3V.

[05]

Thanks. Thinking more about that, might have been easier to just use 5V tolerant esp8266 :)

[announcer4614]

Fair point, I hadn't thought to consider that aspect of the ESP8266. I mainly opted for the shiny new ESP32-C6 with the idea that I might one day set it up to use Thread instead of WiFi.