Trouble with MOSFET and ESP32

Using my ESP32 I am able to switch a MOSFET (IRF510) to blink an externally powered LED but not other things.
E.g. if I connect a brushless fan motor (that does work with as little as 3V) instead of the LED the motor does not spin at all.

Here is my minimal working example of this problem (also see picture):
Gate <-> D25
Drain <-> LED Cathode (-) / motor GND
Source <-> 3V Power supply GND and ESP32 GND
3V Power supply GND <-> LED Anode (+) / motor 3V

What I have tried:

  1. Switch to IRF1310F: same result
  2. Switch to IRF Z44N: LED is on all the time
  3. Switching to another DC motor: same result
  4. Adding a 10k resistor between Gate and Source: same result

I feel like there is an obvious solution to this. However I just can't see it.
Looking forward to any pointers in the right direction. Thank you!

None of those MOSFETs are logic level. All of them have Rds(on) specified at 10V so will not turn on fully at 3.3V. Check the wring and pinout of the IRFZ44N.

A IRL510 has Rds(on) specified at 4V so is a better choice.

  1. Adding a 10k resistor between Gate and Source: same result

The use of a gate resistor has been debated on this forum before. Many say that none is necessary. I always use gate resistor. The gate resistor is to limit the current while charging the gate capacitance. 10K is way too much and will cause the MOSFET to turn on slowly and waste power as heat.

Welcome to the forum.

Please read the post at the start of any forum , entitled "How to use this Forum".

As @groundFungus has pointed out, you will need to use a logic level MOSFET.
You will also need a current limit resistor with the LED.

Tom... :slight_smile:

I got a IRL540N (the closest to the recommended IRL510N I could get my hands on today) and now everything works like a charm. :slight_smile: Thank you groundFungus!

Good to hear, now all we need is a circuit diagram and this thread will be complete.

Thanks.. Tom.. :slight_smile:

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