1 kV, 8 A fast recovery in a TO-220AC
The STTH810D is a general-purpose fast recovery diode from STMicroelectronics, rated for 1000 V reverse voltage and 8 A average rectified current.
85 ns trr — snubber and switching-loss implications
The 85 ns reverse recovery time places this diode in the fast-recovery class, suitable for hard-switching topologies like PFC boost, output rectification in flyback converters, and snubber circuits. Compared to standard recovery diodes (trr > 500 ns), the STTH810D reduces turn-off losses and allows higher switching frequencies without excessive snubber dissipation. The 2 V forward voltage drop at 8 A is typical for a 1 kV-class fast diode — expect about 16 W conduction loss at full rated current, which the TO-220AC package must shed through a heatsink in continuous operation.
Through-hole mounting and thermal path
The TO-220AC package has a metal tab that is electrically common with the cathode. In a typical PFC or boost circuit, the tab is bolted to a heatsink at system ground potential — confirm isolation if the heatsink is chassis-grounded and the cathode is not at ground. The 175°C junction rating gives extra margin over the usual 150°C limit, useful in high-ambient environments like motor drives or sealed power supplies.