Fast recovery rectifier for 100 kHz switching
The STTH1R02Q is a 1.5 A, 200 V fast recovery diode from STMicroelectronics' STTH1 series, in a through-hole DO-15 axial package. Its 30 ns reverse recovery time keeps switching losses low in hard-switched topologies up to 100 kHz — think PFC boost, flyback secondary, or output rectification in a 48 V bus converter.
Forward drop and conduction loss budget
Forward voltage is 1 V maximum at 1.5 A, so conduction loss hits 1.5 W at full rated current. In free air, the DO-15 body needs the PCB copper or a clip-on heatsink to keep junction temperature below the 175°C absolute maximum — derate current above 100°C ambient. Reverse leakage is just 3 µA at 200 V and 25°C, but it doubles roughly every 10°C rise. At 125°C junction, expect leakage in the hundreds of microamps — still acceptable for most offline supplies, but worth checking if the diode sits in a high-impedance node.
Package and assembly fit
It solders into a 0.040-inch plated through-hole on a 1.6 mm board — no special pad geometry needed. The body length is 7.6 mm, so it fits most axial diode slots without lead forming. Available in cut tape or tape-and-box for hand assembly or low-volume production. The base part number STTH1 covers the whole family; the Q suffix denotes the DO-15 package variant.