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UCC21520: UCC21520 and UCC5310 power supply Question in half bridge

Part Number: UCC21520

Dear TIer,

I have question about single / two channel ios-gate driver.

Why single channel iso-gate driver no use bootstrap circuit in main popular half bridge design?

It looks like a PWM IC with two auxiliary lines is used, whereas the 2-channel iso-gate driver uses a bootstrap circuit.




Power deliver iso side

Tow aux wire


Chip unit



  • Hi,

    Single channel drivers can also be used in a half bridge design. So yes, we can still use a bootstrap supply. Typically single channel driver are used to either drive high or low side separately, but dual channel drivers are almost always used in a half bridge design. This is why we mention bootstrap circuitry in dual channel drivers, but it can also be applied to any half bridge configuration. Single channel drivers also typically are powered by bias supplies.