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I read in other questions that is not possible to use 100% DC as PWM input for drivers that use a bootstrap/charge pump to shift the gate levels.

I'm talking about common brush DC motor gate drivers, like these:

I don't find in the datasheets any requirement for the PWM input signal. Which parameter should I check to find out if I can reach 100% PWM?

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  • \$\begingroup\$ Make those IC numbers a link to the datasheet, I've done the first, you do the rest. Most datasheets show a block diagram from which you can deduct if a gate driver is suitable for DC signals. It is assumed that from the block diagram you understand how the gate driver works. Gate drivers with a bootstrap circuit generally do not work for DC and need constant switching. \$\endgroup\$ – Bimpelrekkie Feb 16 at 11:48
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    \$\begingroup\$ The ICs you list all use a bootstrap circuit so are unsuitable for DC. But what if you limit the PWM signal to 99%, it will be difficult to notice that 1% difference and could be enough to make the bootstrap circuit work. \$\endgroup\$ – Bimpelrekkie Feb 16 at 11:53
  • \$\begingroup\$ Open the data sheet. Press CTRL-F then type "boot". In the FAN73832 there are 5 occurrences of the word boot or bootstrap. \$\endgroup\$ – Andy aka Feb 16 at 11:56
  • \$\begingroup\$ @Bimpelrekkie, sorry, I always put the links but nobody told me it was a good thing. The first time I didn't I've been told to do :) I'm going to add them in a while! \$\endgroup\$ – Mark Feb 17 at 6:58
  • \$\begingroup\$ @Andyaka, it's the other way around: I selected those datasheets because they have the "bootstrap" or "charge pump" inside! But if there is a requirement for the PWM input to be < 100% I must find it into the datasheet. I've never seen an "implicit" requirement based upon the alleged knowledge of the users. \$\endgroup\$ – Mark Feb 17 at 7:00

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