IGBT BSM75GB170DN2 ...

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Original poster: "Rajesh Seenivasan" <rajeshkvs-at-hotmail-dot-com> 

Dear forum members,

I have got few BSM75GB170DN2 IGBT modules, which I am planning to use in my 
tesla coils.
The data sheet says:
"RG on,min = 22 Ohm"
I believe that this is the minumum gate resistance that should be used. Is 
this true ?

Description of the gate drive circuit i'm goign to use:
The output from TL494 is fed to optocoupler. Optocoupler's output is given 
to UCC37321 and the
output of UCC chip drives the IGBT gate through a gate resistance (3 ohms 
very low value in my
case). The power for this gate drive circuit is taken from a 0-12V/1A 
transformer, rectified, filtered.
When i measure the gate drive waveform, it is a square wave 0-15V. when i 
use a larger gate drive
resistor (> 6 ohms), the gate drive waveform is not a square wave, but has 
very very slow rise time.
If the gate resistance is lesser or equal to than 3 ohms, the square wave 
for gate drive has good
shape.
So, here is my question:
Will the IGBT or its gate be destroyed if the gate resistance in my circuit 
is less than 3 ohms ?

Thanks in advance.
Rajesh.