what is differential transistor

[ehsanelahimirza]

hi all

plz tell me what is a differential transistor and what is its gain how it is calculated.
i mean accross which nodes or what else
plz give the circuit if necessary

thanks

 

[m.salehi]

hi
it is a differential structure of two transistors.
source of two transistors that connected to each other.
transistores that has two drain, two gate and one common source.

voltage gain = diference of drain voltage of two transistor divided by diference of their gate voltage .

 

[shobhitkukreti]

simple circuit .. just visualize wut i am writing::

take two npn transistors .. connect their collectors 2gether with a + supply
their emitter together in series with a single emitter resistance with -suppy.
and the two inputs at the two bases respetively.
The Output is taken b/w the two collectors.

still confused .. get a book on Opamp fundamentals and look for differntial amplfier