1200 V, 110 A, 58 ns trr — what this HEXFRED module delivers
The VS-HFA220FA120 is a Vishay HEXFRED® fast recovery diode module rated for 1200 V DC reverse and 110 A average forward current per diode, with two independent diodes in one SOT-227-4 miniBLOC package. Its 58 ns reverse recovery time (trr) keeps switching losses low in hard-switched topologies like boost PFC stages, output rectifiers in welding inverters, and IGBT snubber clamp circuits.
Switching loss and thermal budget
At 100 A forward current the maximum forward voltage drop is 3.6 V, giving a conduction loss floor of 360 W per diode at full load — the heatsink must handle that plus the switching loss from the 58 ns trr. Reverse leakage at 1200 V is 75 µA, negligible at 25 °C but rising with junction temperature; the datasheet's thermal derating curve sets the safe operating area for continuous 110 A DC per diode.
Package and mounting — SOT-227 miniBLOC
The SOT-227-4 (miniBLOC) package is a chassis-mount module with screw terminals for the anode and cathode connections and a metal baseplate for direct heatsink attachment. Two independent diodes in one module let you build the high-side and low-side of a half-bridge leg without separate discrete parts, saving board space and bus-bar routing.
No official successor or pin-compatible second source is listed on the record; for dual-sourcing resilience, confirm the BOM position and compare the thermal and switching characteristics of other 1200 V, 110 A-class fast-recovery modules in SOT-227.