Avalon PSU Flyback Small Board for Avalon Miner Power Supply Repair

Avalon PSU Flyback Small Board | 94V-0 Replacement PCB for Avalon PSU3400-03 and PSU3300-03 Miner Power Supply Repair

The Avalon PSU Flyback Small Board is the replacement flyback sub-PCB for the Avalon miner power supplies built by Rspower — specifically the PSU3400-03 and PSU3300-03 models. Drop-in fix when the flyback section fails — restores PSU functionality without scrapping the entire unit. Common failure modes the board resolves: dead auxiliary rail, no startup signal to the primary controller, and oscillation faults on the feedback path.

Built on a 94V-0 flame-retardant FR4 substrate with the standard Rspower flyback topology. Direct replacement for the original sub-PCB inside the Avalon PSU3400-03 / PSU3300-03 housing — same connector layout, same mounting holes, same form factor. Cost-effective repair path versus PSU swap when the rest of the PSU is healthy.

When to Replace the Avalon Flyback Small Board

• PSU dead at startup — primary controller has no auxiliary supply, flyback sub-board failed.
• Auxiliary rail missing but primary side appears alive — flyback section dead, primary controller can't initialize.
• Visible burn or component damage on the flyback sub-PCB — direct replacement, no further diagnostic needed.
• PSU rebuild on a refurbishment line — replace the flyback board proactively on used PSU3400-03 / PSU3300-03 units before redeployment.
• Hum, buzzing or unstable startup on the PSU — magnetics or feedback components on the flyback board degraded.

Avalon PSU Flyback Small Board Specifications

FAQ — Avalon PSU Flyback Board

Q: Does this board fit other Avalon PSU models beyond PSU3400-03 / PSU3300-03?
A: This specific flyback sub-PCB is built for the PSU3400-03 and PSU3300-03 by Rspower. Earlier and later Avalon PSU revisions may use different flyback topologies — confirm against your PSU model number before ordering.

Q: Can I replace this board without specialized tools?
A: The flyback sub-PCB sits inside the main PSU housing. You'll need to open the housing, disconnect the sub-PCB harness, unfasten the mounting screws, and reinstall. No reflow or chip-level work — a screwdriver and basic electrical safety are sufficient.

Q: How do I confirm the flyback board is the failed part vs the main PSU PCB?
A: Power the PSU on a current-limited bench supply and probe the auxiliary rail — if it's missing while the primary stage shows life, the flyback board is the culprit. If the primary is also dead, the fault is elsewhere.

Q: Bulk pricing for repair shops?
A: Yes — email contact@lys-sz.com with your monthly volume and we'll send tier pricing.

Related products

• Avalon PSU3400-03 Power Supply – Canaan A1346 / A1366
• Avalon PSU4100-03 Power Supply – Avalon Q
• Avalon Test Fixture Data Cable 14P / 60cm
• Avalon PSU 2-in-1 Power Supply Fan Simulator

Repair shops rebuilding Avalon PSU3400-03 / PSU3300-03 in volume? Email contact@lys-sz.com for bulk pricing on flyback boards and matching PSU parts. Worldwide shipping from our Shenzhen warehouse.