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Old 01-25-2011, 12:24 AM   #4256 (permalink)
DJBecker
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I haven't seen any design guidelines that suggest a power supply for each driver. Certainly you want good decoupling caps, following the usual guidelines: a small ceramic cap to damp the high frequency noise, and a bulk cap with low ESR that is more than 10x the combined gate charge to supply the instantaneous current.

If you connect the gate driver outputs together, you will get some amount of shoot-through. Even with perfect matching and putting them on opposite ends of the board, the power use will go up, perhaps way up.

The only reason I could see to connect the outputs of two gate drivers in parallel is to drive a single really big devices. The answer used to be to use a little gate driver feeding a totem-pole stack of big bipolar transistors. But today you can just buy a bigger gate driver. I've never used one, but my jaw dropped when I read the datasheet on this part:

IXDN430YI 30A 0.4ohm 35V TO-263-5 $4.40
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