DRV8300: Dead time defination and calculation

Will Wang47

Part Number: DRV8300

Hi team,

I'm working with customer on DRV8300. They get one question about the dead time.

Where does the DT time start? In the following figure, does it start from the fall edge of INH or the fall edge of GH? This matters, for there is a tPD between INH and GH, this time will effect allow since the DT is usually ns second level.

After dead time, will there by a tPD time in the GLx signal as I marked below?

Hope you could share some comments on those two question. Thanks.

Best Regards,

Will

over 2 years ago

+1 Michael Arrant over 2 years ago

TI__Expert 3535 points

Hi Will,

The deadtime is added before the prop delay of the driver. In other word, the deadtime is at the input of the driver.

The prop delay component will add in both GLx and GHx after the deadtime block. So your picture is correct, the dead time will scoot over a bit.

Figure 8-3 a simplified version of the inputs/outputs.

Thanks,

Michael

0 Will Wang47 over 2 years ago in reply to Michael Arrant

TI__Expert 5510 points

Hi Michael,

Thanks for your feedback.

Does it mean that in the above figure 8-3, dead time is added after the INHx fall edge, not the GHx fall edge, correct?

0 Michael Arrant over 2 years ago in reply to Will Wang47

TI__Expert 3535 points

Hi Will,

Yes, that is correct.

Thanks,

Michael

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DRV8300: Dead time defination and calculation