| Old Schematic (Pre-2020) | Updated (UPD) Version | |--------------------------|------------------------| | No soft-start circuit | Added C5 (1µF) from COMP to GND for soft-start | | Direct feedback from optocoupler | Series resistor + diode (R14, D7) for better transient response | | Single current sense filter | Dual RC filter (R9-C7 + internal leading-edge blanking) | | 50kHz oscillator | Increased to 65kHz to reduce transformer size |

| Ref Des | Old Value/Part | New Value/Part | Reason | |---------|----------------|----------------|--------| | IC1 | [old] | [new] | EOL / better efficiency | | Rxx | [value] | [value] | Adjust feedback loop | | Cxx | [rating] | [rating] | Ripple improvement |

On the secondary side:

A high-voltage capacitor (C854) typically shows ~310V when active. Voltage Test Points