Using a driver (IRS21844S) without the boot cap circuit

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Hi, I'm trying to figure out how to use an H-Bridge driver chip without resorting to the boot strap cap method. The FETs themselves are switching a +96V circuit, and what I'd like to do is connect a +108V signal directly to Vboost. Is this possible? What other considerations do I need to make or take into account?
Thanks, Dan B.
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Daisy_T
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Hello Dan,

The AGND should be connected to DGND for this IC. And please add a small capacitor between Vb and Vs as a filter.

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Daisy_T
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so yo mean no bootstrap circuit is used in your application, and use a 108V connected to the VB pin, 96V to VS pin. Then please use a capacitor between VB and VS as a filter, the IC will work as expected.
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Hi tengD, thanks for getting back to me. Here is the circuit I have now:

2990.attach

I'm going to add an isolated DC-DC converter to the circuit. And if I understand correctly, I should connect it like this?
2991.attach

Thanks again! Dan B.
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Daisy_T
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250 sign-ins 250 replies posted 25 likes received
Hello Dan,

The AGND should be connected to DGND for this IC. And please add a small capacitor between Vb and Vs as a filter.
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