This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

UCC5350-Q1: RMS current calculation

Part Number: UCC5350-Q1

Hi Team,

My customer Preh has a question about the UCC5350-Q1:

How to calculate the RMS current for gate drivers.
4x Gate Driver UCC5530 for H-bridge control are in use and a Gate Driver will each drive an IGBT, which each IGBT 650nC gate charge has.
The switching frequency with approx. 50% duty cycle is f_sw=60kHz.
The 15V_supply supplies VCC2 at the gate driver. A transformer inductance must be dimensioned at the input of the 15V_supply and for this I need the RMS current.

1) is the RMS current calculated like this?

I_RMS_per_driver= Q/t_on =650nC*8,3µs=78mA
I_RMS_total:= I_RMS_per_driver*2 = 156mA (2x gate drivers activated simultaneously)

2) or so?
Charge is converted as a capacitor.

Calculate Tau:

The current curve during capacitor charging:
Peak current I_OH_nom is calculated as in the data sheet=15V/7.6ohm=1.97Ampere

Then the RMS current is calculated for the t_on duration:

I_RMS_total=IG_on_nom_RMS*2 = 537mA (2x gate drivers activated simultaneously)

Thanks and best regards