0
\$\begingroup\$

I'm newbie in electronics looking for an advice on how to properly limit gate voltage for BUZ11 MOSFET in my PWM regulator for a DC motor. Currently I'm using it with 12V power supply and it works OK, but I want to use it with 25,2V (LiPo 6S), so the gate voltage should be limited to < 20V. Thinking about Zener diode 1N4745A (16V). Will it work for schematic below?

Schematic (for 12V power supply): enter image description here

Zener diode:

enter image description here

UPD I'll also use 78L12 LDO to power NE555.

\$\endgroup\$
4
  • \$\begingroup\$ It might, but that won't be the only problem - the NE555 can only hande 18V so it would also fry if connected to 25V. \$\endgroup\$
    – Justme
    Commented Oct 5, 2021 at 12:32
  • \$\begingroup\$ Oh, I've forgot to mention that I'll use 78L12 LDO to power NE555. \$\endgroup\$
    – Mr D
    Commented Oct 5, 2021 at 15:32
  • 1
    \$\begingroup\$ If you would use 12V linear voltage regulator for powering the NE555 why would you think you'll need to "protect" a MOSFET? \$\endgroup\$
    – NStorm
    Commented Oct 5, 2021 at 15:55
  • \$\begingroup\$ @NStorm, so if I'm using LDO to power NE555, then I'm also limiting it's output to MOSFET. Actually, I haven't thought about it. \$\endgroup\$
    – Mr D
    Commented Oct 5, 2021 at 18:49

1 Answer 1

1
\$\begingroup\$

The zener will be useless as you seem to be powering the NE555 with 12V, so you don't need any protection for FET gate.

\$\endgroup\$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.