low parts count 2kW inverter

Author	Message
analog8484 Senior Member Joined: 11/11/2021 Location: United States Posts: 198	Posted: 05:35pm 01 Feb 2026         poida said   it is 1oz copper, if it shows promise I will make a v.2 with 2 oz copper, error fixes, unused footprints removed and space for 3rd main cap. I have 3 similar inverters to compare. this one, the first version of it that uses TIP41/42 transistors in the totem pole type gate drive and Wiseguy's inverter with it's professional design. All 3 require about 1330 W input to drive the same load. Maybe Wiseguy's inverter used 1300 W but the load varies over time so it's hard to get it accurate. The next thing to examine is gate drive signal shapes and look for shoot through at idle and under load. Cool.  Look forward to your findings.   poida said   I varied gate drive voltage while running under load and changing from 12 to 15V made no difference to input power. Not surprised since the gate caps are fully charged by 10V according to the datasheets.  I have tested some HYxxx MOSFETs at 10V and 12V and didn't see any significant difference.   poida said   Finally, I might need to put "some" resistance in the gate drive, at the moment the FET gate is direct connected to FOD3182 output and I suspect there is MHz oscillation. No doubt that is causing some shoot through. That's a bit surprising.  Besides shoot through, the RFI/EMI can be pretty bad as well without any external gate resistance.