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Basic Electronics

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R - - - - - ~ ~ - - - - ~ - - ~

VI Output VI Output

Figure 3(a) Figure 3(b) (8)2. (A) The transistor in the circuit in Figure 4 has parameters Vm (threshold voltage)=

0.8V and Kn (conduction parameter) =0.25 mA/V2 Determine the powerdissipation in the MOSFET when (a) Vvv=4V, Rv=l kQ and (b) Vvv=5V, Rv=3k.Q. What is the operating bias region: for each condition?

' .

Ro

Figure 4(B)The open loop gain ofthe OPAMP (shown in Figure 5) is 103

Determine the output voltage V0 when VF2V.10kn

10kn

Vo100kn100kn

Figure 5' .

(5)

(10)

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(C) Calculate the small signal voltage gain of he circuit shown in Figure 6, forMOSFET transconductance parameter gm= 1 mAIV, MOSFET output resistancer0=50 kn and RD=10 kQ.

Figure 6(5)

3. (A) Determine the de current /z through the circuit shown in Figure 7. Both thetransistors have threshold voltage Vm = 1 V, 1= 0 and conduction parameterKn (L-MOSFET) = 10 J1AN2, Kn (D-MOSFET)= 50 J1AN2 Also determine V0for VF5V.

Voo=5V-

Vo

Figure 7(10)

(B) Calculate the bias current ofM1 in Figure 8. Assume process conductionparameter kn=lOO J1AN2 and threshold voltage Vnv=0.4V. Ifthe gate voltageincreases by 10 mV, what is the change in drain voltage?

; . .

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Also find what choice ofR0 places the transistor at the edge of the nonsaturationregion with Vas=1V?

VDD=1.8V

1~ R o = 5 k . Q WA.=210.18M1

Figure 8(10)

4. For all transistors in Figures 9(a) and 9(b), 13 = 75, fmd the values of

' .

(i) Collector current /c and resistance Rc for Figure 9(a).(ii) Base voltage VB and resistance Rc for Figure 9(b).

+10V

Rc

+VcE=4V

-10V

Figure 9 (a)

Ra=25kn

(4)

+5V

la=0.5 rnA

Vc=-1V

Rc

-5V

Figt.lre 9 (b)(10+10)