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(ELEC102)final_paste.pdf
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Text Box: Given that VO / V1 = 11 , find V1 / VS in terms of R, C and jw. If C = 1.YF and R = 1k.., find the complex tran




Text Box: Circuit is a low pass filter

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VZK = 7V

rZ = 10.

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when T = T/2, Vi= 4 V, D is OFF

VO= Vi + Vc = -11 C9= -20 V

Vc = -9V

3V

3V

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Text Box: (a) In the ideal diode circuit, find Vc and sketch Vo(t). Show clearly the voltages in your sketch. Assume the diode




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T

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Text Box: . Vi = 6 cos 2.1kt V. Plot the waveform of VO(t) . Show also that the ripple voltage Vr of VO(t) is about 0.2V




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e

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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 active mode, describe the movement of ele




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RC = 2k.

RB = 10k.

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





AssumeBJT is in active mode

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Hence BJT is in saturation mode

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Hence BJT is in saturation mode

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Text Box: Given the BJT circuit below and the IC -VCE curve of the BJT. (a) Draw the load line VCE = VCC - ICRC and locate



Vin1 = 0.75V
IB1= 0.10mA

Vin2 = 0.73V
IB2 = 0.06mA

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Draw load line, Q point,

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(b)

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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.

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


NMOSFET is in triodemode

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Text Box: (c) If IDS = 3mA, find the mode of the MOSFET. Given VT = 1V
Text Box: VGS = VG .V VS = 5V .V 0V = 5V
Text Box: VGS > VT

Text Box: VGS - VT > VDS