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Why is transconductance called gm?

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Elektroniko

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A simple question, why is transconductance called gm? What does the g and the m stand for?
 

esp1

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The symbol 'g' is used for Conductance.

The gm value is Idt/Vdt, also called the mutual conductance, so its notation is gm.
 

LvW

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The symbol 'g' is used for Conductance.

The gm value is Idt/Vdt, also called the mutual conductance, so its notation is gm.

I suppose, Eric means: gm=dI/dV.

Because we have the dimension current/voltage=1/Ohm, this ratio gives a conductance g.
However, it is not a "classical" conductance that relates the current through a device and the voltage across THIS device.
Instead, it is a current through a certain node (collector, drain) related to a voltage at ANOTHER node (base, gate).
Therefore, it is a "mutual" conductance gm.
 

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