A UD2.7 rebuilt around a Raspberry Pi Pico so that it can phase-shift. The sheet brings out Out and ShiftedOut on separate UCC27525 drivers, each into its own pair of WSF4012 FETs. Those are the two halves whose relative phase makes the ramp. Feedback and overcurrent run through GS8743 comparators, with a TPS54302 and an LD1117S33 for the rails. MIT licence, with gerbers, an interactive BOM and the schematic published.
The author notes his own compromises on the drawing: “Overshooting the phase lead and then tuning it with an RC filter so theres no need for kinda rare variable inductors”; “Couldn’t switch pins in the code fast enough, so decided to implement a simple OR gate”; “Will be replaced with just the RP2040 after I work out all the issues”; “This is a bit cursed, but solved all startup issues and it works well so…”; and on the gate resistors, “need to be picked according to the fet gate charge to avoid cross conduction”. The silkscreen calls the board “Nebula’s ‘UD3 we got at home’”.
No photograph of an assembled board turned up. The repository’s only image is the 3D render shown here, and a web search for the author finds nothing else, so the card is labelled render, not photo.
Schematics and photos
schematic: Pico, two UCC27525 on Out and ShiftedOut, WSF4012 pairs
Sources
This is the card from the driver tree, written from what the builder published. Send corrections through the forum.