An ESP01 controller is paired with a buck converter module to provide an efficient 3.3 volt supply. Three separate channels are provided with open drain MOSFET outputs to drive LEDs up to 24 volt.

Example software is built using PlatformIO and Homie. To use OTA programming the flash chip on the ESP01 needs to be upgraded to 4MB to provide sufficient room for the current and update software images.

The example software provides independent timed sequence with fading for one to three channels, so ideal for controlling everything from fairy lights to RGB light strips. A Homie broadcast is used to synchronize sequences across multiple units and requires a millisecond timestamp to be posted periodically, for example by using a cron task. Christmas light displays can now be created across multiple rooms, multiple households, or even across a whole community!

A simpler software without timing and synchronisation might support OTA in a basic 1MB flash.

PCB is designed to fit into a Hammond 1551R box. For low profile the ESP-01 and PSU modules need to be soldered into the PCB.

The hole size for the regulator module will take socket but is too small for 0.6mm pins; turned pin connectors will fit okay.