Hello,
We are making a inverter using IRP4668 Mosfets and FOD8316 Gate Driver . A system of single Mosfet was tested and was running fine.
Now we are planning to use 5 Mosfets in parallel.
We are planing to change power supply for Gate driver and use tidu478. As I think we would need a higher continuous and peak current while driving 5 Mosfets in Parallel.
From Infineon we got this formula to know the Gate current req:
Qg =I*t.
Where,
Qg is the Mosfet gate charge,
I is gate drive current,
t is turn on time.
Now if I assume that I want 200nS as my Turn on time i.e. t= 200ns with my Qg is 241nC as per IRP4668 datasheet.
So for Qg =I*t,
I get,
Igate = 241nC/200ns = 1.205A.
And as I have 5 Mosfet in parallel,
Hence,
Itotal = Igate * 5 = 1.205*5 = 6.025A..
But the power supply i.e. tidu478 which we are planing to use can provide only 100mA of rated current but it has 6A of peak current handling capacity.
So I wanted to ask that:
1. Will tidu478 work? or I need to get power supply which provide 6Amp continuous current. Which sounds suspicious to me!
2. What are proper formulas to find continuous and peak current requirement from Gate driver's power supply (DC-DC) for driving single Mosfet?
3. What are proper formulas to find continuous and peak current requirement from Gate driver's power supply (DC-DC) for driving 5 Mosfet in parallel?
