IRF4905 datasheetIRF 3205 Datasheeet

I am working on a 24-volt BLDC 3ph drive application.

I have made this design with a basic understanding of p and n channel MOSFET.

In this design, MOSFET gate pulse is in voltage range of 18-20 volt.

I am quite confused about choosing the correct value gate resistor. I found that it must be within 20-50 ohm. I applied many combinations but still, the problem lies the same as the previous one.

I also found that maybe the dead band is not quite enough that will make MOSFET hotter so I changed it accordingly. From 1us to 3.2us. But still no change in temperature.

Please note that the gate pulse is coming from the Allegro based BLDC driver A4963. I am also attaching schematic of it.

What can I do to reduce the heating?

• N channel: IRF3205
• P channel: IRF4905
• Driver asic A4963 Allegro