I'm a bit confused about something about BJTs and MOSFETs. My understanding was that MOSFETs tend to be better for power switches since they have a positive temperature-resistance coefficient, can switch at higher frequencies, lower power drive circuitry, and a resistive conduction characteristic that is low enough such that at most current levels the losses are less than a BJT's diode conduction characteristic (the voltage drop across the FET S-D resistance is less than the BJT's C-E diode voltage drop for the same current).
But here is where I get confused. Now, the BJT doesn't have the base capacitance like a MOSFET has a gate capacitance, and yet it switches slower? BUt then I read about BJT's are often used to drive FET gates because they can supply more current and are can turn on faster- except, I thought the MOSFET could supply more current due to its low S-D resistance compaed to the BJT's C-E diode voltage drop.
I'm a bit confused.
EDIT: From what I have gathered since I posted this, it seems some of the differences involve the output impedances, but I don't know much more than that.
But here is where I get confused. Now, the BJT doesn't have the base capacitance like a MOSFET has a gate capacitance, and yet it switches slower? BUt then I read about BJT's are often used to drive FET gates because they can supply more current and are can turn on faster- except, I thought the MOSFET could supply more current due to its low S-D resistance compaed to the BJT's C-E diode voltage drop.
I'm a bit confused.
EDIT: From what I have gathered since I posted this, it seems some of the differences involve the output impedances, but I don't know much more than that.
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