Hi If the orig part used is a irf3205 55v mosfet can a fqa140n10 100v mosfet be used instead with 2 irf 3808 75v mosfet in an input stage on power inverter the battery is 12 volts or am I better off with the irf3205 or all irf 3808? data sheets are on digikey
I would avoid paralleling power MOSFETs. Unless the layout is perfectly symmetrical with a gate resistor right at each MOSFET, they will often oscillate while in the linear region or while passing through the linear region in a switching application.
This is a mass china made pure sine inverter not a home made inverter the input has a row of mosfets and gate resistor are before and after each mosfet. The orig part is irf3205 is the fqa140n10 a good substitute? I was thinking since the fqa140n10 continous drain amps are higher the inverter wattage output would go up is this correct?
The FQA140N10 is not a direct substitute for the IRF3205. The two important differences are the ON resistance of 10 vs 6.5 milliohms and the total gate charge of 220 nC vs 76 nC. Note that the FQA gate charge is calculated for a higher drain voltage but it's still too high. The higher gate charge will slow down the rise/fall time and result in increased power dissipation.
The irf3205 are 110a 55v rds on its 8mega ohm http://www.irf.com/product-info/datasheets/data/irf3205.pdf
there are apparently 2 types of irf3205
With this new info is a fqa140n10 a good substitute for irf3205pbf or not? note there is plenty of room for a to-247 on the heat sink
It will work but will run hotter. If you have them already you might as well try them.
The IRF3205 is $2.53 in single quantities at Digikey and the FQA140N10 is $5.35. If you're going to order them you might want to order the IRF3205.