Is there a PWM chip that can properly drive an H bridge? (with deadtime, fast on and off times etc)?thanksi

Most of the DSP chips designed for motor drive that I've looked into -- ADI, Freescale, TI -- do this.Dunno about discrete chips, though.-- Tim WescottWescott Design Services

Here's where I am a little confused. I thought that snubber capacitorsplaced across the IGBT would protect them during "dead time". It is a digitally controlled Hobart CyberTig. You can see it here: It is rated for 200A maximum. (and it does put out 200A).If I set it to operate at, for instance, 137A, that would be veryclose to its actual output.Open Circuit voltage 80V, typical arc voltage 30V.i

PWM chip that can drive an H bridge?

Oct 06, 2005 43 Replies

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Ignoramus30105 20 years ago

Here's where I am a little confused. I thought that snubber capacitors placed across the IGBT would protect them during "dead time".

It is a digitally controlled Hobart CyberTig.

You can see it here:

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It is rated for 200A maximum. (and it does put out 200A).

If I set it to operate at, for instance, 137A, that would be very close to its actual output.

Open Circuit voltage 80V, typical arc voltage 30V.

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Ignoramus30105 20 years ago

I think that my IGBT's already have catch diodes (formed like a bridge also). Toshiba-MG200Q2YS40.

See file Toshiba-MG200Q2YS40_DAT-IGBT.pdf

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Chris Jones 20 years ago

That will happen anyway when the electrode gets lifted too far from the metal and the arc goes out. But the OP is going to put varistors across the supply, I hope. Chris

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Don Foreman 20 years ago

You might find something at

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