Ultrafast recovery for PFC and flyback snubbers
The STMicroelectronics STTH2R06S is a 600 V, 2 A ultrafast rectifier with a 50 ns reverse recovery time, housed in a DO-214AB (SMC) surface-mount package. It is designed for high-frequency power conversion — think power-factor-correction boost stages, flyback snubber clamps, and output rectification in switch-mode supplies where switching losses matter. The 50 ns trr keeps the recovery spike low enough that you can run the switching frequency up without cooking the diode. Junction temperature range extends from -40°C to 175°C, so it handles the thermal cycling in an outdoor telecom rectifier or an automotive on-board charger without derating.
The 50 ns reverse recovery time is the number that defines this part. In a continuous-conduction-mode PFC stage, a slower diode (say 200 ns) would dump charge back into the MOSFET at turn-off, raising the drain voltage spike and the EMI floor. At 50 ns, the stored charge is low enough that you can pair it with a 600 V MOSFET without an extra snubber in many designs. The 1.7 V forward drop at 2 A is typical for this voltage class — not the lowest Vf, but the speed is the trade-off. If your load is under 1 A, the Vf drops, and the recovery time stays the same.
The DO-214AB (SMC) body is large enough that you can hand-rework it with a hot-air station without worrying about the adjacent passives. The SMC footprint is about 7.1 mm x 6.1 mm, so it takes a standard 2 A copper trace without a thermal pad. MSL 1 out of the bag, no bake needed unless the reel has been open in a humid environment past the floor-life window.
If you need a second source, the STTH2R06 is the same die in a different package variant; the STTH2R06S is the SMC version.