200 V, 3 A ultrafast recovery in a DO-15 axial package
The STTH3R02QRL is a 200 V, 3 A ultrafast recovery diode from STMicroelectronics, part of the STTH3 family. Its 30 ns reverse recovery time (trr) places it in the fast recovery class (≤500 ns, >200 mA), making it suitable for high-frequency rectification in switch-mode power supplies, PFC boost stages, and freewheeling circuits where switching losses matter.
30 ns trr and 175°C junction — what they mean for your design
With a 30 ns trr, this diode recovers fast enough for a 100 kHz+ switching converter — the stored charge clears quickly, so the MOSFET or IGBT turning on sees less reverse-recovery current spike. That translates to lower switching losses and less EMI in the snubber loop. The 175°C maximum junction temperature (Tj) gives headroom in a hot enclosure. If the diode sits on a PFC heatsink near a 85°C ambient, the 3 A average current can be sustained without derating as long as the thermal resistance to ambient is kept below about 30°C/W. Forward voltage is 1 V typical at 3 A — so at full load the conduction loss is 3 W. That is manageable in a DO-15 package with adequate lead length and copper pad area on the PCB. Reverse leakage is only 3 µA at 200 V, which keeps standby losses negligible in a lightly loaded supply.
DO-15 axial — through-hole fit for PFC and secondary rectification
The DO-204AC (DO-15) axial package is a through-hole footprint. It is common in PFC boost stages, output rectification on flyback converters, and freewheeling diodes across relay coils or motor windings where a surface-mount part might not handle the thermal cycling. The axial leads can be formed for vertical or horizontal mounting on the PCB. The part is supplied in Tape & Reel (TR) or Cut Tape (CT) — the reel format suits automated insertion for volume builds, while cut tape works for prototypes or small-batch rework.
Active lifecycle and compliance
STMicroelectronics lists the STTH3R02QRL as Active — no end-of-life notice or last-time-buy window. It is ROHS3 compliant, so it fits EU and global BOMs without exemption paperwork.