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This won't work as you want. For a start the BS170 is an N channel mosfet and does not have a collector or emitter. Secondly you are attempting to describe it being wired as a source follower - this will not amplify the gate drive voltage at all. In fact it's likely you'll get a smaller gate drive voltage onto the IRFZ44.

What you could do is have the BS170 wired with source to 0V and drain to the gate of the IRFZ44 - you will also need a pull-up resistor from drain to 12V. The action will be inverted i.e. when you formally produced a 3V3 gpio output, this will now turn off the IRFZ44.

If you can't live with the inversion then a PNP transistor can be made to work but the base drive to it is a little more complex. Given the speed you need to drive PWM I'd use a proper driver like this: -

enter image description here

Try googling "mosfet driver chip".

This won't work as you want. For a start the BS170 is an N channel mosfet and does not have a collector or emitter. Secondly you are attempting to describe it being wired as a source follower - this will not amplify the gate drive voltage at all. In fact it's likely you'll get a smaller gate drive voltage onto the IRFZ44.

What you could do is have the BS170 wired with source to 0V and drain to the gate of the IRFZ44 - you will also need a pull-up resistor from drain to 12V. The action will be inverted i.e. when you formally produced a 3V3 gpio output, this will now turn off the IRFZ44.

If you can't live with the inversion then a PNP transistor can be made to work but the base drive to it is a little more complex.

This won't work as you want. For a start the BS170 is an N channel mosfet and does not have a collector or emitter. Secondly you are attempting to describe it being wired as a source follower - this will not amplify the gate drive voltage at all. In fact it's likely you'll get a smaller gate drive voltage onto the IRFZ44.

What you could do is have the BS170 wired with source to 0V and drain to the gate of the IRFZ44 - you will also need a pull-up resistor from drain to 12V. The action will be inverted i.e. when you formally produced a 3V3 gpio output, this will now turn off the IRFZ44.

If you can't live with the inversion then a PNP transistor can be made to work but the base drive to it is a little more complex. Given the speed you need to drive PWM I'd use a proper driver like this: -

enter image description here

Try googling "mosfet driver chip".

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source | link

This won't work as you want. For a start the BS170 is an N channel mosfet and does not have a collector or emitter. Secondly you are attempting to describe it being wired as a source follower - this will not amplify the gate drive voltage at all. In fact it's likely you'll get a smaller gate drive voltage onto the IRFZ44.

What you could do is have the BS170 wired with source to 0V and drain to the gate of the IRFZ44 - you will also need a pull-up resistor from drain to 12V. The action will be inverted i.e. when you formally produced a 3V3 gpio output, this will now turn off the IRFZ44.

If you can't live with the inversion then a PNP transistor can be made to work but the base drive to it is a little more complex.