This years ornament was a revisit of the 2019 tree, but with the construction design of three interlocking PCBs from 2021’s snowflake. A familiar electrical design based on a single AA battery, 3V boost, STM32F030 MCU, ambient light sensors and a matrix of RGB LEDs driven from the MCU directly with some PFETs.
48 RGB LEDs were placed on the tips of each branch with various animations of colours. 3 PCBs with double sided loads provided a significant amount to hand assemble, with the added complexity of this being the first RoHS compliant assembly.
Fred Temperton 