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1. The JFET is(a) a unipolar device(b) a voltage-controlled device(c) a current-controlled device(d) answers (a) and (c)(e) answers (a) and (b)

e

2. The channel o a JFET is between the(a) gate and drain(b) drain and source(c) gate and source(d) input and output

b!. " JFET alwa#s operates with

(a) the gate-to-source pn $unction reverse-biased(b) the gate-to-source pn $unction orward-biased(c) the drain connected to ground(d) the gate connected to the source

a4. For %&'  %* the drain current beco+es constant when %,'

eceeds(a) cuto(b) %,, (e) %P (d) %

c/. The constant-current area o a FET lies between

(a) cuto and saturation(b) cuto and pinch-o 

(c) and l,'' (d) pinch-o and brea0down

d

. l,'' is(a) the drain current with the source shorted(b) the drain current at cuto(c) the +ai+u+ possible drain current(d) the +idpoint drain current

c. ,rain current in the constant-current area increases when

(a) the gate-to-source bias voltage decreases(b) the gate-to-source bias voltage increases(c) the drain-to-source voltage increases(d) the drain-to-source voltage decreases

a

3. n a certain FET circuit. %&'  %* %,,  1/%. l,''  1/ +"*and 5,  4 6. 5, is decreased to !! 6* loss is

(a) 17./ +"(b) 1./ +"(c) 1/ +"(d) 1 +"

c7. "t cuto* the JFET channel is

(a) at its widest point(b) co+pletel# closed b# the depletion region

(c) etre+el# narrow(d) reverse-biased

b1. " certain JFET data sheet gives %&'(o)  -4 %. The pinch-o 

voltage %P*(a) cannot be deter+ined(b) is -4 %(c) depends on %&' (d) is 84 %

d

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11. The JFET in 9uestion 1(a) is an n channel(b) is a p channel(c) can be either

a12. For a certain JFET* &''  1 n" at %&'  1 %. The input

resistance is

(a) 1 :6(b) 1 :6(c) 1 :6(d) 1 +6

c1!. For a certain p-channel JFET. %&'(o)  3 %. The value o %&' 

or an approi+ate +idpoint bias is(a) 4 %(b) %(c) 1.2/ %(d) 2.!4 %

d14. " :;'FET diers ro+ a JFET +ainl# because

(a) o the power rating(b) the :;'FET has two gates(c) the JFET has a pn $unction(d) :;'FETs do not have a ph#sical channel

c1/. " certain ,-:;'FET is biased at %&'  %. ts data sheet

speci