i need to modify a little on original pcb.
There are only a few schematic changes. 1. Add DIP Switch. In a previous version there was a SIP alongside the DIP, but we dont need that extra 8-pin connector. 2. Delete J7. 3. On each driver channel, disconnect the pullup resistor from 3.3V and tie instead to the PWM signal. I made a sketch here attached. This affects 6 resistors, R6 through R39. This change will also improve the ground plane continuity. 4. Eliminate U12 and connect the 3V nodes to regulator on page 1. At the same time, change U6 to a 3-terminal 3.3V regulator,