(SOLVED) Drop voltage - drain to source voltage - using IRL520N

Continuing the discussion from 615 coreless motor mosfet:

I tried to do the same as the schematic above and I found the voltage drop (drain to source voltage) from 3.7v to 0.64 volt in max throttle but turned to 3.7 volt in min throttle. Is this normal?

For this experiment, I use 720 dc motor. I will use 8520 coreless dc motor later.

Do you think 10K resistor is too big. How about 1K?

Between the "output pin" and the Gate?
(If so, in either case: much too much.)

No, but drain to source.

For the sake of clarity --

There are 1k resistors between the output pins and the IRL Gates. Shouldn't be > 100Ω.
No Drain-to-Source resistors are shown. There should not be. Or what are you trying to do?

it was written above the motor.

Is it the cause of the drop voltage? okay, I will remove 1KΩ and add 100Ω

He noted "between first and last leg".
That would be Gate to Source, which is Gate to GND.

image

Yes, I added like it. Gate to source.

Do you ken the difference between "Gate and Source" and "'output pin' and the Gate" ?

As far as I can see, gate is the control and source is where the power flows in it.

That's the answer to a different question.

From the schematic you show, the resistor should not be gate to GND/source, right? :slight_smile: :hugs: Is that what you mean? wait, I'm soldering them now to test.

I tried it and measure again and I see only 0.4 the voltage drop. Thank you for the best solution. :heart_eyes: I learn a lot here.

Now I know that the source is ACTUALLY a positive power flow.

This guy looks like he has had a rough life.

Nasty soldering and you're right. I built many projects of Quadcopter (for 3 years - rough life) and now I'm going to try using ESP32 lol. Don't you realize that God sends you here to solve my problem. YOu're the best. Thanks again.