BQ40Z50-R1: Mosfet Rgs 10M function

Che yi Su

Part Number: BQ40Z50-R1
Other Parts Discussed in Thread: BQ27742-G1

Hi,

BQ40Z50-R1 suggested to connect a 10M ohm resistor from Mosfet Gate to Source, but I found BQ27742-G1 without this suggestion.

1. What's diffierent between BQ40Z50-R1 and Bq27742-G1?

2. Can I remove this 10M ohm resistor when I use BQ40Z50-R1? What's condition need to consider when I remove it?

over 7 years ago

0 Batt over 7 years ago

TI__Mastermind 42535 points

No, you can't remove it. That's for a proper pulldown. Otherwise you will leave the terminal floating.

0 Che yi Su over 7 years ago in reply to Batt

Expert 1695 points

Hi Batt,
Thanks for your reply. Why BQ27742-G1 can remove it?

0 Batt over 7 years ago in reply to Che yi Su

TI__Mastermind 42535 points

Che Yi,

I believe that for a 1s application the drive across the fet was not that high on the bq27742-G1. However in the bq40z50-r1 you need a clear pull down to be absolutely sure the fet's turn off. That's why you need the 10M. Also, the devices are not from the same IC or the same family. So you cannot compare them.

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BQ40Z50-R1: Mosfet Rgs 10M function