What the 80 ns reverse recovery time means for your design
The STTH1L06U is a 600 V, 1 A fast-recovery diode from STMicroelectronics, built for continuous-conduction-mode PFC boost stages, flyback snubbers, and secondary-side rectification in medium-voltage switched-mode power supplies. Its 80 ns reverse recovery time (trr) is the key switching parameter: it cuts the recovery charge that a MOSFET or IGBT must absorb during turn-off, keeping the switching node clean and reducing ringing. At 1 A forward current the forward voltage drop is 1.3 V typical, which sets the conduction loss budget for a 1 A average load. The junction is rated to 175 °C, giving thermal headroom in a cramped PFC layout or a high-ambient telecom rectifier.
That means no last-time-buy scramble and no forced redesign for a replacement.