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I am trying to understand the difference between synchronous buck MOSFET drivers and synchronous boost MOSFET drivers.

I have a full bridge converter which can also only be used as buck or boost. I use a half bridge driver to drive each of the two legs.

The drivers are only used for level conversion and impedance conversion, the control is realized by a microcontroller.

So far I use the driver NCP51513. During the search I came across some drivers like NCP5901B or NCP81151B, which are designated as buck driver. However, I do not understand why these drivers could not be used for a boost circuit.

The converter is used for input/output voltages from 2 to 12V.

UPDATE enter image description here

Due to a question here the configuration of the power stage. Besides the buck boost operation can also be used as a full bridge to control a motor.

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    \$\begingroup\$ Can you spell out whether any terminals on input and output can be common? There may be a difference more easy to see considering to use a "boost converter gate driver" in a buck converter. \$\endgroup\$
    – greybeard
    May 28, 2023 at 8:07
  • \$\begingroup\$ Take a look at the update \$\endgroup\$ May 28, 2023 at 9:19
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    \$\begingroup\$ (While I find the jumpers to the "half bridge bearings" surprising, I can sort of see GND allowed to be common.) \$\endgroup\$
    – greybeard
    May 28, 2023 at 9:28
  • \$\begingroup\$ Please think about what I say: focus on a specific problem you have and ask a specific question. At the moment it is unclear what you are asking of this site. \$\endgroup\$
    – Andy aka
    May 28, 2023 at 11:20

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I don't see a difference between these three drivers either. The suggested applications are, as best I can tell, just that -- suggested applications.

I would avoid the latter two (5901, 81151) just because of smell: they appear to be poorly-written translations, so may be making other omissions or errors that aren't so obvious.

Beware that these drivers do not indicate any kind of charge pump to maintain the high side supply, so they will not work for 100% duty cycle output. This isn't a problem for a buck/boost, but may be a problem for a motor control. A charge pump can be added easily enough, or a driver integrating one can be chosen.

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