BQ78Z100: BQ78z100 MOSFET GS resistance select issue

Skate Lu

Intellectual 870 points

Part Number: BQ78Z100

As shown in the picture, R7, R8=3M, Will affect the stability of the circuit work?

And the recommended value of R7, R8 is10M.

over 6 years ago

0 Kang Kang over 6 years ago

TI__Mastermind 24870 points

Can you clarify your concern? These are tied to the gate. Are you concerned about the stability. These resistors are there for current limiting.

0 Skate Lu over 6 years ago in reply to Kang Kang

Intellectual 870 points

I am a little worried about charging and discharging FET off, I can also measure the output voltage if I use 3M resistance.

Because my product has been shipped, I am not sure if there is any other problem.So I'd like to hear some advice from you.

0 Onyx Ahiakwo over 6 years ago in reply to Skate Lu

TI__Guru* 76230 points

Hi Skate,
That resistor is there to keep fets off when they ought to be off. I think 3M should still be ok, but if there is the option of changing it to 10M, pls do so
thanks
Onyx

Power management

Power management forum

BQ78Z100: BQ78z100 MOSFET GS resistance select issue