Why are the advantages of JFET over MOSFET, or why are JFET still used?
The JFET has several advantages over the MOSFET. The most important are:


higher gain
lower noise


These are the overriding factors when building preamplifiers for low-level signals, such as those from microphones.

Also, since there's no thin gate oxide that can be punctured by ESD, they're a little more "rugged" in that sense.

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