G1N65R035TB-N hybrid normally-off Gallium Nitride GaN FET

G1N65R035TB-N Hybrid Normally-Off Gallium Nitride (GaN) FET – ASIC Miner PSU Repair

The G1N65R035TB-N is a 650V hybrid normally-off Gallium Nitride (GaN) FET built around a cascode topology that combines a high-voltage GaN HEMT with a low-voltage silicon MOSFET. The result is a transistor with the fast switching and low conduction loss of GaN while behaving like a normally-off enhancement-mode device that drops directly into PWM controller designs. It is used on the primary side of high-efficiency ASIC mining PSUs (latest-generation APW17-class units and aftermarket high-power supplies), where switching loss reduction directly buys back wattage that would otherwise be wasted as heat.

Why GaN Matters in a Mining PSU

Conventional silicon super-junction MOSFETs at 650V have a price-performance ceiling — pushing higher switching frequency to shrink magnetics costs efficiency. GaN devices like the G1N65R035TB-N break that compromise: their switching transitions are several times faster, gate-charge is lower, and Rds(on) holds at a useful 35mΩ class. In a 3000-3500W PSU running at 100kHz+, replacing a failed silicon switch with GaN does not change firmware or topology but shifts the loss balance favourably. In a repair context the cascode hybrid is also forgiving — gate drive looks like a regular MOSFET, no special driver needed.

Replacement Procedure

Disconnect the PSU from mains and bleed the primary bulk capacitors (5 minutes minimum, or use a bleed resistor for safety). Identify the failed switch — typically shorted D-S in both directions, often paired with a blown input fuse and a darkened gate-drive resistor. Clear any short on the gate path before fitting the new device. Mount the G1N65R035TB-N in the original footprint, dress the gate trace short and clean (GaN hates parasitic gate inductance), torque the heatsink screw to spec, and bench-test the PSU at low input voltage / current-limited before connecting to a real load.

G1N65R035TB-N Specifications

Related 650V Mining PSU Switches

• TP65H035G4WS 650V GaN FET – High Performance
• UJ4C075060K4S SiCFET – Bitmain APW17 PSU Repair
• SVF7N65F 650V N-Channel MOSFET – Crypto PSU Repair
• LSB65R041GF 650V 78A Power MOSFET

Repairing high-efficiency mining PSUs in volume? Contact us at contact@lys-sz.com for tray-quantity GaN pricing. Worldwide shipping from our Shenzhen warehouse.