Bjt + nmosfet test

The idea of ​​this scheme is to control a 1ohm nichrome resistor (heat it) to melt a wire. I have used BJT transistors and an NMOSFET. I carried out a series of tests… Could you tell me if there are errors in this scheme?

This forum is on using the Kicad software, not a general electronics site. Using the software for a project doesn’t mean it is a Kicad question.

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What @hermit said, but in the meantime: (looking at the right diagram on the 2nd page.

  1. Q1 needs to be an NPN
  2. Q1 needs a base resistor (when you change it to NPN)
  3. R6 is way too high unless you have a high PWN rate.
  4. Source of the NMOS needs to connect to GND.
  5. Not sure 6Volts is enough to drive the NMOS to a really low resistance. Look at its data sheet, in the curves you will see ON characteristics for different gate voltages.

I suggest you get out of the circuit analysis program and try it understand the elements. The circuit analysis program will give you a false sense of progress.


Don’t know how to delete the post.
Thank you for the explanation, it is very help full !
I’ve solved the circuit but yes, it was necessary to understand how really works this elements and after start to burn nichrome.

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Just leave the post, it goes away after some months.

I green lighted the subject as the system held it. I could have killed it then but we try to be helpful to a point. No need to walk away with a bad feeling. If you continue to use Kicad you will probably want some clarifications on it in the future. Good luck with your project. :smiley:

Basically, we have been discussing this recently as a community and I believe this is the majority opinion on how to proceed with posts like these. Give a little help but don’t allow it to go too far off topic.

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