MOSFET control with PWM

V is the output voltage from the power supply and the 4th collum is the percentage from the first to the next amp.

Voltages are always measured between 2 points. So your measurement is between "output voltage from the power supply" and WHAT??????

Hi,
What circuit are you using?
Can you indicate on it where you are measuring current and voltage?

Thanks.. Tom... :smiley: :+1: :coffee: :australia:

And, add the "power supply" under test to the circuit. As a block is sufficient, don't need its detail schematic (yet).

Assuming you are using an effective gate driver, which an Arduino is not. You'll probably get away with it at 20-40kHz, but it's not ideal. In any case don't use 12k at the gate, but a more sane value such as 47R or so. 470R as suggested by @TomGeorge is safe for the Arduino. However, it does still limit the switching speed of the mosfet.

Doesn't look good to me. For instance at 30V and pwm '100' the current is 723mA whereas at pwm '225' (which is 2.25x more) it's 2040mA, while it should have been 723 x 2.25 = 1627mA if the 100-figure would be correct. So either you have a measurement problem, or you have a mosfet driver problem.

if it's an inductive load, should the current be linear with PWM duty cycle?

"real quick" ?
10A thru 0.0135 Ohm is 1.3W

Sim it in LTSpice :wink: You've got a point, but you'd have to do the math to determine if it's valid with the given frequency and I-L-R values.

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