UCC21550: UCC21550 - to Drive High side FET -ON Continuously

AMEY KULKARNI

Part Number: UCC21550

Hello;

I want use UCC21550 for one of motor Drive application. On our application this Driver I.C. is used to Drive a High side MOSFET and a Low side FET. Load is connected between High side FET and Low side FET. Hence we have following Requirements:

1> Both High side and LOW side will be On at the same time . Hence dead Time needs to be disabled.

2> High side FET is required to be continuously on . Hence instead of bootstrap capacitor we will connect an isolated 12V Supply between VSSA and VDDA pins of the I.C. That is a Separate supply to continiously power the high side section.

Please let me know if there will be any issue for above 2 points.

Regards;

Amey Kulkarni

2 months ago

0 Hiroki Honda 2 months ago

TI__Intellectual 2991 points

Hi Amey,

This should not be an issue as long as the dead time function is disabled.

The two channels are independent so it should not be a problem to keep one HIGH.

Regards,

Hiroki

0 AMEY KULKARNI 2 months ago in reply to Hiroki Honda

Prodigy 20 points

Thanks for the reply. For point No 2 that is using a isolated 12V Power Supply instead of bootstrap capacitor, any issue in that?

0 Hiroki Honda 2 months ago in reply to AMEY KULKARNI

TI__Intellectual 2991 points

Hi Amey,

This should not be a problem if this is the desired method of driving the high side. We have seen this application before, however the bootstrap circuit is generally a more cost effective solution.

Hiroki

Power management

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UCC21550: UCC21550 - to Drive High side FET -ON Continuously