I am looking to convert 48-60VDC down to 5VDC (@5A) and need to optimise for efficiency. I have limited thermal capability to remove heat, and also in this application saving 1/2W's ends up being important.
Using traditional Silicon Mosfets, large inductors, and using VCCx gets me to around 92% the major losses now are in teh FETS.
I was considering looking at replacing the Silicon FETs with GaNfets which have very low Rds and very Low Gate charge..
Currently i'm using a BSC340N ( Fet to +V ) and BSC190N ( to GND ).. they have Rds of .07 and 0.02 ohms respectively.
If i replaced those with a EPC2001, ( epc-co.com/epc/Portals/0/epc/documents/datasheets/EPC2001_datasheet.pdf )
Rdson is 0.007Ohms, and Qg to 7nC.
It results in an overall power saving of around 1.2W, which is another 4% or so, halfing my power loss. Futher optimization of frequency may result in better results, if i can increase the frequency and reduce the inductor value.. ( for a lower resistance ).
There are no free lunches in engineering.. The Fets are 3x the price ( at least ),
Does anyone have any other pointers of what might go wrong?
