20 A, 350 V fast recovery diode — what the 35 ns trr buys you
The ROHM RFN20NS3STL is a standard fast recovery diode rated for 350 V reverse voltage and 20 A average rectified current, with a reverse recovery time of 35 ns. This trr figure places it in the fast-recovery class — under 500 ns at currents above 200 mA — making it suitable for continuous-conduction-mode PFC boost stages and the output rectification stage of a 200-240 VAC input SMPS, where switching losses at 50-100 kHz are dominated by the diode's recovery charge.
Forward drop and leakage — the thermal budget drivers
Maximum forward voltage is 1.35 V at 20 A. Reverse leakage is 10 µA at 350 V — low enough that the leakage contribution to the junction temperature rise is negligible at 150°C maximum junction temperature, but the leakage curve at elevated temperature should be reviewed against the actual operating VR for designs that push close to the 350 V ceiling.
Package and footprint — D2Pak with LPDS variant code
The RFN20NS3STL is supplied in a TO-263-3 (D2Pak) surface-mount package, with ROHM's internal supplier device package code LPDS. The D2Pak footprint is a standard high-current power package with a large copper tab for heatsinking. The LPDS code indicates a specific lead-frame or mold-compound variant — the land pattern should match the standard TO-263-3 pad layout, but the exact package drawing should be used to confirm the tab dimensions and lead coplanarity before committing the PCB.
Lifecycle and compliance — active, no LTB risk
It is ROHS3 compliant, clearing EU regulatory requirements for new designs.