SCT51240TWBR Gate Driver for Power MOSFET Iceriver PSU Repair

SCT51240TWBR 24V / 4A Wide-Supply Low-Side Gate Driver | High-Speed Replacement for Iceriver BP-H-3640 PSU Repair

The SCT51240TWBR is a 24V / 4A wide-supply low-side gate driver for power MOSFETs, IGBTs, and wide-bandgap GaN devices. Used on the Iceriver BP-H-3640 power supply to drive the primary-side switching MOSFETs at high frequencies — the kind of high-speed switching where propagation delay and drive-current capability directly limit converter efficiency.

Headline specs for PSU rework: 4.5V to 24V supply range, 4A peak source / sink, 12ns input-to-output propagation delay, 9ns rise / 6ns fall times, and negative input voltage capability down to -5V for ringing-immunity at the driver input. Outputs default to a defined low when the input is floating, so the downstream MOSFET stays off through power-up sequencing — important on a PSU that just lost a primary MOSFET in a fault event.

When to Replace the SCT51240TWBR

• Iceriver BP-H-3640 PSU dead after primary MOSFET failure — the driver usually goes with the MOSFET.
• Sluggish or asymmetric gate waveforms on the primary switch — driver rise / fall times have drifted out of spec.
• PSU enters protection then resets repeatedly — UVLO triggering near the 4.5V threshold or thermal shutdown at 170°C.
• Visible damage on the TSOT23-5L package — burnt or cracked after a primary-side fault.
• Adjacent primary MOSFETs also failed — replace driver + MOSFETs together, never just one.

SCT51240TWBR Specifications

FAQ — SCT51240TWBR Gate Driver

Q: Replace just the driver, or driver + adjacent MOSFETs?
A: Always check the MOSFETs the driver was switching. A shorted MOSFET takes the driver out with a Vgs spike in the same event — replacing only the driver and re-energising the PSU usually kills the new driver in seconds. Replace the MOSFET and the driver together, then re-power.

Q: Why is the negative input voltage capability important?
A: On a low-side driver in a buck topology, the source-side ground can momentarily swing negative during high-di/dt switching events. A driver that latches up on negative input causes asymmetric switching and shoot-through. The -5V tolerance lets the SCT51240TWBR ride through these transients without misbehaving.

Q: Rework profile for the TSOT23-5L?
A: Bottom-side preheat 100°C, top-side hot air 300–320°C with flux paste. Small thermal mass — brief reflow dwell only, avoid prolonged heat which damages adjacent passives.

Q: Bulk pricing for Iceriver PSU repair benches?
A: Yes — email contact@lys-sz.com for reel-quantity SCT51240TWBR pricing and matched MOSFET kits.

Related products

• Iceriver BP-H-3640W PSU Replacement (KS3 / KS3L / KS3M / KS5L)
• Iceriver KS-Series Control Board (KS1-KS5M)
• FAN7391MX High-Current Gate Driver IC
• MD18624GAA Dual Gate Driver (Avalon 1346 PSU)

Iceriver PSU repair benches stocking SCT51240TWBR gate drivers by the reel? Email contact@lys-sz.com for bulk pricing. Worldwide shipping from our Shenzhen warehouse.