1
GATE ECE 2011
+2
-0.6
The channel resistance of an N-channel JFET shown in the figure below is 600 W when the full channel thickness (tch) of 10 μm is available for conduction. The built-in voltage of the gate P+N junction (Vbi) is -1 V. When the gate to source voltage (VGS) is 0 V, the channel is depleted by 1 μm on each side due to the built in voltage and hence the thickness available for conduction is only 8 μm The channel resistance when VGS = 0 V is
A
480 Ω
B
600 Ω
C
750 Ω
D
1000 Ω
2
GATE ECE 2010
+2
-0.6
In a uniformly doped BJT, assume that NE, NB and NC are the emitter, base and collector dopings in atoms/cm3, respectively. If the emitter injection efficiency of the BJT is close unity, which one of the following conditions is TRUE?
A
NE = NB = NC
B
NE $$\gg$$ NB and NB > NC
C
NE = NB and NB < NC
D
NE < NB < NC
3
GATE ECE 2007
+2
-0.6
The DC current gain ($$\beta$$) of a BJT is 50. Assuming that the emitter injection efficiency is 0.995, the base transport factor is:
A
0.980
B
0.985
C
0.990
D
0.995
4
GATE ECE 1999
+2
-0.6
An n-channel JEFT has IDSS = 2 mA and Vp = −4 V. It's transconductance gm (in mA/V) for an applied gate-to-source voltage VGS of –2V is:
A
0.25
B
0.5
C
0.75
D
1.0
EXAM MAP
Medical
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