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FET comparison chart

I've always been confused between JFETS, MOSFETS, Enhancement mode, etc...

Recently I did some reading and have a better understanding at the differences. It appears JFETS are similar to BJTs, however, they have higher input impedance and require negative voltage to turn off. MOSFETS require 0 volts to turn off, and have high impedance.

All I'm pointing out is that I've done some research before I ask my question.

Is there a comparison chart that shows all the variations between the models? It seems MOSFETS require much less gate current than JFETS, but each one has good and bad points.

It would be nice to see a chart laid out.

Thanks in advance.

Reply to
Peter
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In all FETS, the input signal controls the cross section or conductivity of the conducting channel. It how that is done that leads to all the FET variations.

A JFET and BJT are completely different except for the material (usually silicon) used to make them. The conductive channel width of the JFET is controlled by reverse drive on the junction. In structure, it is somewhat similar to a unijunction transistor.

Bill

-- Support the troops. Impeach Bush. Oh, I forgot about Cheney.

Reply to
Salmon Egg

Peter wrote on 07-06-07 20:47 : [...]

MosFETs don't require Gate current, unless you consider very high frequency (Gate capacitance), hence the "Metal-Oxide-Semiconductor" portion of the acronym. Junction FETs do require finite gate current. Before you go further, decide what you mean by "good and bad".

Try undergraduate EE courses and class material, unless, of course, Google is still down.

Reply to
nospam

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