LM25119 MOSFET gate drive levels

Steve Sinn

Other Parts Discussed in Thread: LM25119

I am trying to find the min, typ, & max levels for the Low side MOSFET gate drive pins (LO1&2) & the High side MOSFET gate drive output pins (HO1&2). Is this equal to the VCC level minus some drop?

over 11 years ago

0 Michael Brantley over 11 years ago

TI__Intellectual 1535 points

Steve,

Per the datasheet, the absolute max for the LO pins is –0.3 to VCC+0.3 V, and for the HO pins is –0.3 to HB+0.3 V (HB is high-side driver supply for bootstrap gate drive). It is recommended to stay away from the maximum limits in case of any fluctuations; i.e. LO should be kept from 0 to VCC.

Please refer to the datasheet for all of this information:

http://www.ti.com/lit/ds/symlink/lm25119.pdf

Michael

0 Steve Sinn over 11 years ago in reply to Michael Brantley

Intellectual 435 points

Thanks for the reply. I understand the absolute max numbers. What I am after is the voltage level that is driven out of these pins. ie, what will the gate to source voltage be on the external FETs that these pins drive?

0 Michael Brantley over 11 years ago in reply to Steve Sinn

TI__Intellectual 1535 points

Steve,

I apologize for the confusion. Please see the chart below that I pulled from page 7 of the datasheet. As you can see, during peak LO source and sink currents, VLO ranges from 0 to VCC, and during peak HO source and sink currents, VHO ranges from 0 to VHB.

Does this answer you question?

Michael

0 Steve Sinn over 11 years ago in reply to Michael Brantley

Intellectual 435 points

Got it, thanks!

0 Michael Brantley over 11 years ago in reply to Steve Sinn

TI__Intellectual 1535 points

Not a problem! Please click "Verify Post" on my responses to close out this thread.

Have a good day!

Michael

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LM25119 MOSFET gate drive levels