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DKNguyen
DKNguyen
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If you're PWMing an LED to adjust brightness then the frequency required will be too low for the slow switching of a BJT to matter since you could probably do as low as 30Hz-60Hz and get away with it due to the way the human eye works. Even if you used 120Hz it's not going to matter much. For your case, I don't think it matters much in your case which you use, but you'll have lower gate drive current with a logic level MOSFET than an NPN, whereas the NPN can be driven by very base-emitter voltages voltages (almost down to about 0.7V) since it is controlled by the base-emitter current rather than the voltage.

If you're PWMing an LED to adjust brightness then the frequency required will be too low for the slow switching of a BJT to matter since you could probably do as low as 30Hz-60Hz and get away with it due to the way the human eye works. Even if you used 120Hz it's not going to matter much. For your case, I don't think it matters much in your case which you use.

If you're PWMing an LED to adjust brightness then the frequency required will be too low for the slow switching of a BJT to matter since you could probably do as low as 30Hz-60Hz and get away with it due to the way the human eye works. Even if you used 120Hz it's not going to matter much. For your case, I don't think it matters much which you use, but you'll have lower gate drive current with a logic level MOSFET than an NPN, whereas the NPN can be driven by very base-emitter voltages voltages (almost down to about 0.7V) since it is controlled by the base-emitter current rather than the voltage.

Source Link
DKNguyen
DKNguyen
  • 57.3k
  • 5
  • 70
  • 161

If you're PWMing an LED to adjust brightness then the frequency required will be too low for the slow switching of a BJT to matter since you could probably do as low as 30Hz-60Hz and get away with it due to the way the human eye works. Even if you used 120Hz it's not going to matter much. For your case, I don't think it matters much in your case which you use.