• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 63 subscribers
  • Views 169 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

LM74930-Q1: If it is avaliable to put a discharge resistor between the gate and source of the MOS

Ethan Liu
Intellectual 1445 points
Part Number: LM74930-Q1
Other Parts Discussed in Thread: LM74930,

Tool/software:

Hi team,

Regarding the LM74930-Q1 in the ORing circuit, we usually put a discharge resistor (R7, R8) between the gate and source of the mos, as shown in the figure below. But the LM74930 recommended application circuit does not have it, so I want to confirm, if the discharge resistor is put, what effect will it have on the gate drive?

Best regards!

Ethan

  • 0
    TI__Mastermind 47340 points

    Hi Ethan,

    A discharge resistor is not required.

    When the FETs are turned off, they are connected internally to source pins (DGATE to A and HGATE to OUT). 4.7k is a very high value as it will lead to constant sink of around 2.5mA (VGS = 12V) which is very high and constantly load charge pump.

    Even when the device is off, we have a passive pulldown which keeps the FETs off.

    Regards,

    Shiven Dhir