Original poster: "claude masetto" <claudmas-at-optusnet-dot-com.au> Hello list, I'm going to replace the mosfets in my SSTC with IGBT's. I've only bought 2 to try and am going to build a half bridge. I would like to know if I can use the same drive for the gates. Do I still need the 15v back to back zeners and do I still include the fast freewheling diodes across the collector emitter legs. Thanks Claude.