Hi,
i have a question, i need to drive a mosfet (irfz44n), i saw this circuit once, but i dont understand why this circuit is not popular to drive a mosfet, is there any disadvantages of using this circuit? thanks. or maybe i just haven't find the name of this circuit yet...
Depends on the Arduino and the turn on/off speed you need.
The base current for Q1 flows through the emitter collector circuit of Q2 with nothing to limit the current, so is likely to damage either or both transistors.
The only thing discharging M1 gate is the 10k resistor R2 in series with the 1k resistor R1, resulting in M1 turning off slowly, which might or might not be a problem depending on the application.
Posted by a hobbyist with little experience or training?
Why make it hard on yourself by using non-logic level mosfets.
Use logic level fets, like the IRLZ44, so you can drive them directly from an Arduino pin. Note the "F" and "L" in the part number.
This page shows various drive possibilities.
Leo..
yep, i just started to learn more about mosfets and the switching behaviour
i know i can use logic level mosfet, however i just want learn more about mosfets, what variables are importants and why and how is some driver better than the others.
Thanks for the answer though!
- Watch this:
I was referring to the person who originally posted that circuit. They are obviously missing important background knowledge and key concepts.
The only comment I have about that video is skipping too fast over Vgs(th).
Assuming that if Vgs(th) is below 5volt it's OK, which is wrong.
Non-logic mosfets usually have a Vgs(th) value listed of 2-4volt.
Gate threshold voltage should be seen as the fet's turn-off point.
A logic-level fet has it's on resistance, RDS(on), listed at 4.5volt or lower.
Non-logic fets only have a Rds(on)@10volt stated in the datasheet.
Leo..
