Bjt tut 9 1(2003)

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Transcript of Bjt tut 9 1(2003)

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inV outV

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Question 1

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Tutorial 9

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Question 2The amount by which an electrical signal is increased in amplitude

OR

Gain is simply the ratio of output voltage to input voltage.Output current to input current or output power to input power

The frequency response of an amplifier is the change in gain or phaseshift over a specified range of input signal frequencies. The frequencyat which the magnitude of drops to , the cutoffFrequency of the filter. The range, or band, of frequencies below thecutoff frequencies is called the passband. The bandwidth (BW) of anAmplifier is the difference between the upper and lower cutoff frequencies.

BW=f2 – f1

(max)VA (max)(max) 707.02

2VV AA

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Question 4

Question 5

The complete h-parameter equivalent circuit of a common emitter.

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6 (a) Refer to 5(a)

6 (b)

fh -Forward current gain-Measure of the forward current gain measured with the output shorted.

feh -For the common emitter configuration, the lower case e was assed.

-Output admittance (conductance)-Measure of the conductance looking in at the output with the input open.

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Question 6

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Question 7

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Question 7 (Continued)

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Question 8

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Question 8(Continued)

Question 9

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