中国矿业大学2014-2015学年第二学期
《模拟电路基础》 试卷（A 卷） 《Fundamentals of Analog Electronic Circuits 》 考试时间：100 分钟 考试方式：闭卷 2015. 5
学院 班级 姓名 学号
ⅠMultiple Choice )'30(
1、The Thevenin resistance seen between terminals A and B in Fig.1 is .
Ω
ΩΩ
Ω10)(5)(31)(11)(d c b a
Fig.1
2. Which of the following statements is true ? (a) For a resistor, the voltage and current are in phase. (b) For an inductor, the current lags the voltage by 90°. (c) For a capacitor, the current leads the voltage by 90°. (d) All of these are true.
3、The current is A )33377sin(10m t i
-=, and the voltage is
V )20377sin(10 +=t v . The power factor is
(a) 0.6 lagging (b) 0.6 leading (c) 0.8 lagging (d) 0.8 leading
4. Identify the forward-biased diode(s) in Fig.2
(a) D1(b) D2(3) D3(d) D1 and D3
Fig.2
5. Two currents that are nearly the same in normal operation of BJT are
(a) collector and base (b) collector and emitter
(c) base and emitter (d) input and output
6. If R2 in Fig.3 is open, V C will
(a) increase
(b) decrease
(c) not change
7. The voltage across a forward-biased silicon diode is
approximately
(a) 0.7 V
(b) 0.2V
(c) 0V
(d) dependent on the biased voltage
Fig.3
8. The output signals of a CC BJT-amplifier is always
(a) in phase with the input signals
(b) inverse-phased to the input signals
(c) larger than the input signals
(d) exactly equal to the input signals
9. An amplifer of FET with high voltage gain and high input resistance is common-
(a) drain (b) source (c) answers (a) and (b) (d) neither (a) nor (b)
10. A series resonant circuit has a 10-mH inductor, a 0.1-uF capacitor, and a 10- resistor. The resonant frequency (f), in Hz, is close to
(a) 31.620 (b) 5.035 (c) 801 (d) none of these
Ⅱ. Find the power of the i x voltage source in the circuit shown.
)'10(
Ⅲ. The switch has been open for a long time, it is closed at t=0.Find (a) the expression for i (t) when t > 0. (b) the initial energy stored in inductor.
)'10(
Ⅳ．Find the Norton equivalent with respect to the terminals a, b in the circuit shown.
)'12(
Ⅴ. Find the output voltage of the circuit shown.
)'10(
Ⅵ. (a) Design a clipper circuit that has the transfer characteristics shown in the Figure. )'6((You can use batteries resistors, diodes capacitors of any value desire and allow for 0.6V forward diode drops.)
(b) Design a circuit that clamps the negative peaks of an ac signals to +6V.
)'6(
(You can use batteries resistors, diodes capacitors of any value desire and allow for 0.6V forward diode drops.)
Ⅶ. Sketch the small signal equivalent circuit and compute the
voltage gain, the open-circuit voltage gain, input impedance, current gain, power gain and output impedance for the amplifier shown in the Figure. )'16(。