400 V blocking with 500 mA output — the parametric fit
The RMB4S-E3/45: The RMB4S-/45 is a Vishay single-phase bridge rectifier rated for 400 V peak reverse voltage and 500 mA average rectified output current. For a 240 VAC mains input, the peak voltage is 339 V, so the 400 V rating provides 61 V of headroom for line transients and surge events. Forward voltage is 1.25 V typical at 400 mA forward current. Two diodes conduct in series per half-cycle, so the total conduction drop is approximately 2.5 V at that current level. Reverse leakage is 5 µA at the full 400 V blocking voltage — low enough for always-on circuits where standby power matters.
TO-269AA surface-mount footprint
Packaged in the TO-269AA (MBS) 4-pin surface-mount package, the RMB4S-/45 occupies a compact footprint roughly 8.5 mm × 6.5 mm. The MBS outline is a standard for low-current bridge rectifiers and mates with conventional SMD solder pads. The device ships in tube packaging, not tape-and-reel — factor this into pick-and-place setup if the line expects reel-fed parts. The wide temperature range suits applications from outdoor telecom rectifiers to high-ambient power supplies.