Post Go back to editing

faster turn off of the passing fet of LT4356-1

Hi, all

     I am using an RC (10ohm, 47nF) on the gate drive of LT4356-1 to limit the inrush current.

     But I am seeing the capacitor 47nF is discharging very slowly probably due to no drain path. But if I put a scope probe on the gate pin, then it is discharging quite quickly.

     Due to the residue voltage on the cap, the inrush current control is not as effective during fast on-off cycles. I saw the below thread, Zach was saying 'A drain resistor in parallel with the capacitor will speed-up the turn-off of the FET which will help with rapid on/off connections.'

https://ez.analog.com/power/f/q-a/97105/lt4356-inrush-current-issue-with-ltc4015

    Did he mean adding a parallel resistor to the capacitor (in my case 47nF)? But the gate drive strength can be as low as 4uA. The resistor has to be fairly huge. Is my thinking correct?

    Or is there any other recommendation?

    Thank you.

Dyu

Parents Reply Children
No Data