US1M-E3/61T

US1M-E3/61T is a Vishay ultrafast rectifier in an SMA (DO-214AC) package, rated at 1000 V reverse voltage and 1 A average forward current, with forward voltage of 1.7 V and a reverse recovery time of 75 ns — the high-voltage member of the US1x surface-mount rectifier family, for secondary-side rectification, clamp and snubber duty in switching supplies and high-voltage auxiliary rails. The 1000 V rating is the selection point: it is the code to specify where the rectified bus or the ringing on it rules out the 200 V to 600 V siblings in the same footprint. Selection advice: ultrafast recovery is what the US prefix buys over a standard rectifier — at 75 ns it suits switch-mode frequencies where a 1N4007-class part would overheat from recovery losses; the 1.7 V forward drop at 1 A is the conduction-loss figure to budget, and the SMA package dissipates through board copper, so continuous current in a hot enclosure sits below the headline 1 A. The E3/61T suffix is the lead-free tape-and-reel ordering form — quote it in full. Parameters verified against Vishay documentation.