Comments on Using FET based followers and design rules
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Using FET based followers and design rules
Usually, voltage followers are built with bipolar transistors (or with opamps if better precision is needed). In this case, the simple rule says that the transistor emitter "follows" the input voltage one diode drop below, a somewhat approximate but understandable term.
It is perhaps less usual to see field effect based followers, and I'm particularly interested in jfets and mosfets.
From my readings about this topic, it is still unclear to me how to determine the voltage drop introduced by these transistors (parallel to the diode drop for the bipolar transistor follower).
Also, if there is a way to control this drop (without using an opamp), what are the design rules, or perhaps the rules of thumbs ?
Allow me to address the MOSFET only as a source follower. - this has very unpredictable linear use without voltage …
3y ago
"Also, if there is a way to control this drop (without using an oamp), what are the design rules, or perhaps the rules o …
3y ago
FET source-followers are generally less predictable than BJT (bipolar junction transistor, like NPN or PNP) emitter-foll …
3y ago
> ... it is still unclear to me how to determine the voltage drop introduced by these transistors... Very interesting …
3y ago
In addition to Olin's answer: > and I'm particularly interested in jfets and mosfets. If you decide to go dow …
3y ago
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