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Mosfet to PWM a 20V load

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0miker0:
Hello all,
I'd like to pwm a 20V led light strip using an esp32 gpio pin. I have something started below and am wondering if I'm on the right track or have something drastically wrong? Any pointers or tips would be greatly appreciated.

jmw:
Have you tried it in spice? I think those 100k resistors might interact with the gate capacitance of Q3 to skew or wreck your PWM, depending on the period. There are IC PWM LED drivers that will do this for you, or you could also consider a complementary pair topology.

0miker0:
100K is definitely too much and I'm working on correct values now. Checking out other circuits and am wondering if R17 can be completly removed.

ledtester:
Why not just use a single N-MOSFET, eg:

[attach=1]

Zero999:

--- Quote from: 0miker0 on February 02, 2023, 07:49:04 pm ---100K is definitely too much and I'm working on correct values now. Checking out other circuits and am wondering if R17 can be completly removed.

--- End quote ---
Removing R17 will only speed up the turn-on time. R11 means the discharge time is slow, making it take a long time to turn off.

Use a MOSFET driver.

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