30 ns recovery — the switching-speed differentiator
The STTH1R02U is a 200 V, 1.5 A fast-recovery rectifier from STMicroelectronics built for continuous-current mode PFC boost stages, flyback snubbers, and secondary-side freewheeling where the recovery tail of a standard diode would cost efficiency or overheat the junction. Its 30 ns reverse recovery time (trr) places it in the ultrafast class, well inside the Fast Recovery =< 500ns, > 200mA (Io) category — the 30 ns figure is the one that matters for a 70–150 kHz switching edge.
1.5 A continuous and 200 V blocking — where it fits the BOM
A 1.5 A average rectified current (Io) with a 1 V forward drop at that current gives a 1.5 W conduction loss floor before any thermal derating. The 200 V reverse voltage (Vr) provides margin on 48 V and 100 V DC rails, but falls short for 230 VAC offline rectification (which peaks at ~325 V). The 3 µA reverse leakage at 200 V is tight enough to keep standby losses negligible in a bias supply.
SMB footprint and 175 °C junction rating
The SMB body is larger than the SMA sibling, which helps spread heat in a board with limited copper area.
Active lifecycle and compliance status
It is ROHS3 compliant, which clears it for EU and RoHS-restricted markets without an exemption review.