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What is your application?
High side? Low side? Half bridge? Full bridge? Voltage? Frequency? Fixed duty cycle? Mosfet, Bjt, IGBT, SCR, Triac?
Example:
An optocoupler solution to drive a low side mosfet with low voltage, low frequency will be more expensive than direct drive.
An optocoupler solution in a high voltage, SCR switching might be cheaper than a transformer design.
What is your application?
High side? Low side? Half bridge? Full bridge? Voltage? Frequency? Fixed duty cycle? Mosfet, Bjt, IGBT, SCR, Triac?
Example:
An optocoupler solution to drive a low side mosfet with low voltage, low frequency will be more expensive than direct drive.
An optocoupler solution in a high voltage, SCR switching might be cheaper than a transformer design.
The drawback for an optocoupler is that an isolated supply for each of the two top Mosfets.
The advantage is that very narrow or very wide drive pulses, a proper transformer drive requires a lot of thought and testing to do it properly. An otpocoupler is easier, and you can go all the way to 100%
Another drawback is that unless you can find an opto-coupler with fast switching characteristics and high current source and sink capability, it will not be able to provide enough gate current to ensure rapid turn on and off of the MOSFETS. The relatively high gate capacitance of power MOSFETS means you need a large charging current to turn them on and a good sink capability to turn them off.
Note that normal optocouplers are essentially isolated single pole switches, they can be wired to source current or sink it but not both.
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