Que. 1 A long speciman of p type semiconductor material
A is +ively charged
B is electrically neutral
C has an electric field directed along its length
D acts as a dipole
Que. 2 Acceptor impurity atoms in Si result in
A increase forbidden gap
B reduced forbidden gap
C new discreate energy level slightly below conduction leval
D new discreate energy leval slightly above conduction level
Que. 3 in any conductor hall voltage V(H) is proportional to
A B
B B^2
C 1/B
D 1/B^2
Que. 4 In BJT with I(infinite)=1 micro.A, a=0.99,the value of I(CEO) is
A 0.01 micro.A
B 0.001 micro.A
C 1 micro.A
D 1000 micro.A
Que. 5 The current gain of a BJT is
A g(m)*r(o)
B g(m)/r(o)
C g(m)*r(pi)
D g(m)/r(pi)
Que. 6 The velocity of the holes in the n region at X=0
A 12*10^3 cm/sec
B 5*10^3 cm/sec
C 2*10^4 cm/sec
D none of these
Que. 7 The spectral dencity of pink noise varies as
A 1/f^2
B f^2
C 1/f
D f
Que. 8 zener diode is used as a
A current regulator
B voltage booster
C voltage regulator
D power regulator
Que. 9 three phase half wave rectification,if the input frequency is 50hz then
output frequency is
A 100 hz
B 150hz
C 75hz
D 25hz
Que. 10 For getting low regulated voltages are used
A zeners
B SCR
C transistor
D chopper
Que. 11 thin film components are formed
A are made of ceramic
B are made of silk screening process
C are formed by photomaskingand diffusion
D can be made entirely from tantalum
Que. 12 in n-channel FET's are superior to p-channel FEY's because
A they have lower switching time
B they have lower pinchoff voltage
C they have higher input impedance
D mobility of charge carrier e- in n-channel FET is greater than
the mobility of charge carrier holes in p-channel FET
Que. 13 Which of the following device has the highest input impedance
A npn transistor
B JFET
C UJT
D MOSFET
Que. 14 the FET
A has 3 pn-junction
B use a forward bias junction
C depands on the variation of a magnetic field for it's operation
D depands on the variation of a reverse voltage it's operation
Que. 15 transistor in monolithic IC's
A are made as separate wafer
B use isolation junction as the collector junction
C are similar to discrete planner transistor but have the collector
constants on the top surface
D are identical with discrete planner transistor
Que. 16 encapsulation of a transistor is done to
A provide mechanical reggedness
B prevent photo electric effect
C prevent electrical interference
D to case heat radition
Que. 17 The most important factor groverning the cost of IC component is
A the shape of the component
B area occupied by the component
C number of electrode connection
D location of the component on the slice
Que. 18 Extremely low power dissipation and low cost per gate can be achieved
in the following IC
A ECL
B CMOS
C TTL
D MOS
Que. 19 The following digital IC family can give maximum fan out
A ECL
B PMOS
C CMOS
D HTL
Que. 20 in SCR the turn off time
A increases with increases of T
B is independent of T
C varies as 1/T
D varies as 1/T^2
Que. 21 In industrial electronic control
A AC power system are always used
B IC's can be used with advantage in feedback control ckt
C we are simply conceened in establishing stable control with constant
load conditions
D use of IC's is not of consequence
Que. 22 An IC sence amplifier
A consists of a linear amplifier a voltage level detector and a
logic pulse forming ckt
B cannot practically made as a standerad probuct
C is a memory system
D consist of four seperate linear amplifier
Que. 23 Forbidden energy gap between valance band and conduction band is least
in the case of
A mica
B pure Si
C pure Ge
D impure Si
Que. 24 At 0degreeK Forbidden energy gap in Si is
A .785 eV
B 1.21 eV
C .72 eV
D 1.1 eV
Que. 25 acceptor impurity atoms in a result in new
A wide energy band
B narrow energy band
C discrete energy leval just below conduction leval
D discrete energy leval just above conduction leval
Que. 26 relative dielectric constant of Si is
A 12
B 14
C 16
D 20
Que. 27 Diffusion constant for free e- in Ge expressed in (cm^2/sec) is
A 13
B 40
C 34
D 99
Que. 28 when Ge is doped with penta valent impurity,the resulting material is
A p-type semiconductor
B n-type semiconductor
C intrisic semiconductor
D no longer semiconductor
Que. 29 microwave IC's
A have inferior performance
B are not possible to fabricate
C always use discreate components
D are initally being made as hybrid type on ceramic substrates
Que. 30 cost of monolithic IC is
A independent of the quantity produced
B roughly proportional to the area of ckt wafer
C proportional to the number of ckt elements
D increases with increase of quantity produced
Que. 31 The main advantage of TRAPATT diode over IMPATT diode is it's
A higher output
B higher efficiency
C lower noise
D capability to operate at higher freq.
Que. 32 in an unbiased pn junction the junction current is equilibrum is
A due to diffusion of majority carriers
B due to diffusion of minority carriers
C zero due to equal and opposite currents crossing the junction
D zero because no charges cross the junction
Que. 33 In Ge diode the cutin voltage is about
A 0.2v
B 0.6v
C 1.1v
D 2v
Que. 34 In a pnp transistor operating in the active region the concentration of
minority carriers holes in the n region at collector junction
J(e) is
A zero
B thermal equilibrium value p(no) of emittor
C thermal equilibrium concentration of holes in collector region
D same as at J(e)
Que. 35 In the uniformly doped abrupt p-n junction, the doping level of the n-side
is four times the dopinglevel of the p-side. the ratio of the deplation
layer widths is
A 0.25
B 0.5
C 1.0
D 2.0
Que. 36 An n-channel JFET has a pinch off voltage of Vp=-5v,Vds(max)=20v and
(delta)(m)=2mA/V.The minimum 'ON' resistance is achieved
in the JFET for
A V(gs)=-7v, V(ds)=0v
B V(gs)=7v, V(ds)=0v
C V(gs)=0v, V(ds)=20v
D V(gs)=-7v, V(ds)=20v
Que. 37 The reverse saturation current of a solar cell is 10 and the light generated
short ckt current is I for 1 sun illuminated. the open ckt voltage of
the solar cell under one sun illumination is
A KT/q ln(1+I(L)/I(O))
B q/KT ln(1+I(L)/I(O))
C KT ln(I(O)+I(L))
D KT ln(I(L)-I(O))
Que. 38 The need of centre tap is eliminited in full wave_______ rectifier
A vacuum tube
B semiconductor
C crystal diode
D bridge
Que. 39 When a lossy capzcitance with a dielectric of permittivity e and conducitivity
o- operates at a freq. w, the loss tangent for the capacitor is given by
A wo-/e
B we/o-
C o-/we
D o-we
Que. 40 Micro-program is
A The name of the source program in microcomputer
B the set of instructions indicating the primitive operations in
a system
C the general name of a MACRO'S in assembly language programming
D the name of program of very smallsize
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