Bitmain APW17 1215a Power Supply Repair Components List

The Bitmain APW17 1215a is the air-cooled power supply shipping with the Antminer S21 and S19j XP. Rated 12V–15V DC out at 267A on the main rail, plus a 12.3V/18A auxiliary rail (OUT2), it delivers over 3,200W per unit under a 220–277V AC input. Like every high-density switching supply running 24/7 in a mining room, it accumulates wear in predictable places. The good news for operators with bench capacity: most APW17 failures are repairable for $10–$50 in parts and 30–60 minutes of labor, versus $259–$449 for a complete replacement unit. This guide is a structured components list — every board position, every part name, and the LYS replacement we stock for each — followed by the diagnostic order we use in our Shenzhen workshop.

APW17 1215a Power Architecture (How the Components Fit Together)

Before troubleshooting, map the supply mentally. The APW17 uses a two-stage primary topology with a dedicated digital secondary controller:

Input stage. AC enters through the C20 inlet, passes a ceramic fuse, then hits the inrush-current limiter (MF72-class NTC thermistor in series), followed by a mechanical bypass relay (RF-SS-112DM-A) that shorts out the NTC once the bulk capacitor has pre-charged. A bridge rectifier converts AC to pulsing DC and a 500V 390uF (35×38mm) bulk electrolytic stores the energy at roughly 380V DC.

Primary switching — main power stage. The heart of the APW17 is an LLC half-bridge resonant converter controlled by the L6599AD resonant controller IC. The LLC stage drives the main transformer through SiC MOSFETs (UJ4C075033K4S, UJ4C075060K4S in board positions Q11, Q10, Q16, Q17) plus a 0SG65R038HZ high-voltage MOSFET on the high-side switching path. K39N60W5 (TK39N60W5) silicon MOSFETs sit alongside on the auxiliary switching positions.

Primary switching — auxiliary stage. A separate quasi-resonant flyback feeds the 12.3V/18A OUT2 standby rail and the internal control electronics. The flyback is controlled by the PN8149W IC at U27.

Isolation barrier. Feedback and signaling cross the safety barrier through optocouplers (PC817 4-pin through-hole) and digital isolators (NSi8221W1D at U21, with NS166 supporting at U10/U11).

Secondary rectification & filtering. SI7N65F 650V 7A N-channel MOSFETs sit at Q46/Q44 as synchronous rectifiers on the secondary side. Solid-polymer capacitors (1000uF 25V class) handle output bulk filtering, with 0603-pkg ceramics on the high-frequency loops.

Secondary digital controller (the "PIC chip"). A Microchip PIC33EP16 dsPIC microcontroller sits at U13/U20 — this is the digital brain of the secondary side. It handles miner communication, voltage commanding, telemetry, sequencing, and protection logic. When operators say "the PIC chip on the APW17," they mean this part. It's wholly different from the PN8149W or L6599AD PWM/resonant controllers, which are dedicated analog ICs for switching the power MOSFETs.

Analog feedback & monitoring. LM358 dual op-amp at U25 handles general-purpose analog buffering. TP2262 (3PEAK) voltage amplifiers at U22/U19/U23 provide precision sensing for the digital controller. YL3G3AG (U16) is a small LDO regulator; 85572XS8 (U17) is a specialty driver.

Cooling. A pair of 60×25mm 12V fans pull heat out of the chassis. Spec-sheet noise floor is 45dBA. Any audibly worse fan = end of life.

APW17 1215a Components List (BOM Position → LYS Replacement)

Every part below is mapped to its board reference (where available from the schematic), the exact P/N, its function, and the stocked replacement on lys-sz.com. Where a specific OEM part isn't stocked under its exact P/N, contact us at contact@lys-sz.com — we can usually source the equivalent within 48h.

Input Protection & Rectification

Primary-Side Power Switching

PWM & Resonant Controllers

Isolation Barrier

Secondary Digital Controller, Op-Amps & Auxiliary ICs

Magnetics, Diodes & Passives

Cooling, Connectors & Cabling

Diagnostic Order — The Sequence We Use on the Bench

1. Visual inspection. Burn marks, swollen or leaking caps, oxidized connectors, dust-clogged fans, melted housing. Five minutes that saves hours.
2. Fan check. Bench-power both 60mm fans on 12V. If either is slow, noisy, or won't spin freely, replace both — they age together.
3. Fuse and bridge rectifier. Continuity test on the ceramic fuse; diode test on the bridge rectifier. Open fuse = downstream short, almost always a primary MOSFET. Don't replace the fuse alone — you'll blow the new one.
4. NTC and bypass relay. Check the MF72 NTC isn't open-circuit (it shouldn't read >30Ω cold). Verify the RF-SS-112DM-A relay clicks during pre-charge.
5. Primary MOSFET diode test. With the 500V bulk cap discharged, diode-test every primary MOSFET drain-to-source: K39N60W5, UJ4C075033/060K4S, 0SG65R038HZ. Any short = replace; check the gate driver IC simultaneously.
6. L6599AD startup voltage. Apply low-voltage current-limited bench power; verify the L6599AD's Vcc rail comes up and the IC begins switching. No switching = dead L6599AD.
7. PN8149W aux-rail check. Verify the 12.3V auxiliary rail comes up first (the aux rail powers the L6599AD and PIC33EP16). No aux = dead PN8149W or its surrounding flyback components.
8. Loaded output test. Once the PSU powers up cold, connect a dummy load via the APW17 PSU tester. Verify output voltage, ripple, and protection thresholds.
9. Hot-soak 60min. Run the PSU at full rated load for an hour. Thermal protection trips, output drift, or fan ramp-up during this period catch the 5–10% of faults that pass a cold test but fail in production.

Repair-vs-Replace — The Operator's Math

A typical APW17 repair touches 2–4 components ($10–$50 in parts) plus 30–60 minutes of bench time. A new APW17 1215a replacement unit runs $259–$449 depending on grade and source. At any reasonable labor rate, repair lands well under a third of replacement cost — and that's before shipping and downtime.

Triage exceptions: PSUs with multiple-stage failures (primary short + secondary cap fatigue + fan wear simultaneously) or visible PCB damage from a catastrophic event are usually faster to part out for good components than to rework. The repair pattern that scales: keep a small stocking inventory of high-failure-rate parts on the bench (fans, MOSFETs, L6599AD, PN8149W, PC817 optos, NSi8221W1D isolators, P13/P14 connectors), a tester, and a soldering station. With that kit, you turn around 80% of APW17 failures the same day.

Sourcing & Shipping Notes

Every linked part is QC-tested and stocked in our Shenzhen warehouse. Parts with "sourced on request" in the table above are not in continuous stock but can usually be supplied within 48h — email us at contact@lys-sz.com with the BOM reference and quantity.

USA and European Union orders ship DDP (all duties and taxes prepaid, no surprises on delivery). Rest of world ships from China; local customs may apply depending on jurisdiction.

Keep Your APW17 Fleet Running

The APW17 1215a is a repairable, parts-supported platform — not a disposable unit. With a tester, a parts kit, and a consistent diagnostic order, most failures turn around in under an hour at a fraction of replacement cost.

→ Bitmain APW17 1215a Replacement PSU

→ APW17 PSU Tester & Fault Detector

→ L6599AD LLC Resonant Controller

→ PN8149W Quasi-Resonant Flyback Controller

→ UJ4C075060K4S SiC MOSFET

→ 60×25mm Cooling Fan

For bulk parts pricing or a full APW17 repair kit pre-assembled to your fleet size, contact us at contact@lys-sz.com or via WhatsApp. Worldwide shipping from our Shenzhen warehouse.