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PART B
Answer any 2 questions. Each question carries 10 marks.
9. a) Parameters of FET used in amplifier circuits are gm=4.2 mU and ೧730142, Assume C to
be short circuit for signal frequency, given a small signal model for the amplifier.

Determine small signal voltage gain if Ro=6.8KQ, २५ = 10/6) and Rs=10 KQ.

vs

(2.5) b) Compare JFET with MOSFET.
(2.5)
௦) Why is voltage divider bias relatively stable against changes in டி? 11) Design voltage divider
bias circuit to operate from a 12V supply. The bias conditions are

Vce=3V,Ve=SV and [= 1111. (5)

10. a) A transistor used in CE connection has the following set of h parameters when the d.c.
operating point is ५४८5 =5V and Ic = 1 mA; hie 51700 Q ; hye =1.3 10-4; hee = 38; ‏عمط‎ = 6
x 10 ൦0. If the ೩.೦. load प, seen by the transistor 2 60) , find (i) the input

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