The PB3508-E3/45: The PB3508-/45: The Vishay PB3508-/45 is a single-phase bridge rectifier in a through-hole 4-SIP PB package, rated for 800 V peak reverse voltage and 35 A average rectified current. It uses standard silicon technology and is housed in the isoCINK+™ PB package, which provides a compact, high-thermal-performance footprint for a 35 A device. The 800 V peak reverse rating gives a comfortable margin for 240 VAC mains rectification (where the peak is ~340 V) and covers 400 VAC three-phase-to-DC conversion after accounting for line transients. The 35 A average current is the continuous DC output limit — the actual forward voltage drop of 1.1 V at 17.5 A means conduction losses are roughly 19 W at half-rated current, which sets the heatsink requirement.
Thermal and electrical margins for the power stage
The 10 µA reverse leakage at 800 V is a low figure for a 35 A bridge — it keeps standby dissipation negligible and limits thermal runaway risk at high ambient temperatures. The through-hole package (isoCINK+™ PB) is designed for vertical board mounting, which simplifies heatsink attachment and airflow routing in a bulk supply.