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(ELEC102)test2_pastl.pdf
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4

(12)

(12)

(a)



Text Box: . In the ideal op amp circuit, the diode equation is . whe
Text Box: If V2 = - 0.62V D is a ON diode




(12)

4

(4)

VO= Vi + Vc = -10 C10= -20 V

Vc = -10V

(8)

(b)



Text Box: (b) In the ideal diode circuit, find Vc and sketch Vo(t). Label clearly VO(t) . Assume the diode is ideal. (12)




(13)

(c)

Vi > 4.6

10k.



Text Box: (c) In the diode circuit, sketch and label clearly VO(t) . D2 is an ideal diode and D1 is an offset diode with
Text Box: VO




VZK = 7V

rZ = 5.

5

(22)

(7)

(15)



6

(16)

e

(10)

1. EBJunction is a forward bias (on) diodeand BC is reverse bias (off) diode
2. E is very heavily doped(N +for NPN). E has many electrons,
3. B is very thin. So most electronsinjected from E (to B) are attracted to C and

Text Box: Draw the cross sectional structure of a NPN BJT transistor operated in the amplifier mode, describe the movement of





7

VO(t)

RC

RB

Vi= 0.74V


Text Box: Given the BJT circuit below and the IC -VCE curve of the BJT. The Q point is chosen as IC = 16mA and VCE = 5V. (a)
Text Box: vi(t)


VCE2 = 6V

Draw load line,

(8)

(28)

(a)

(5)

(5)

IB = 0.16mA

(10)

(c)

(b)





8

(20)

(a)




Text Box: (a) Find IC / IB . Given RE = 1k.. and Vi = 7V. Show clearly your reasons. For the BJT, given VBE(ON) = 0.






8

(8)

RC = 1k.

RB = 1k.

(8)

(16)

(b)


Text Box: . Draw the small signal (AC) equivalent circuit of the BJT amplifier and find the voltage gain AV ( = Vout / Vin





(15)

ID

IS

source usually shorted to body

Metallic film

IG= 0
ID= IS

An NMOSFET consists of a metal gateinsulated from a p-type semiconductorsubstrate (or body) by an insulating layer of silicon dioxide. On either side of the gate there are n type regions forming the drain and source.

(10)

10

(5)

(b)

(a)




Text Box: (a) Name two advantages of MOSFET. (b) Draw the cross sectional diagram for an enhancement NMOSFET and describe v


NMOSFET is in saturationmode

(6)

(7)

10