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问
（1）What characteristic(s) would be optimal for an ideal op-amp?
[A] Infinite input impedance
[B] Zero output impedance
[C] Infinite gain
[D] All of the above
(2)What is the best way to solve on op-amp oscillation problem?
[A]Try fixing any one of these, and if that doesn't help, leave that fix on, and try another
[B]Add a variable series-R-C damper from ground, to the output or input. Adjust the R and C values
[C]Note the frequency of oscillation.
[D]All of the above
(3)What is the likely cause of oscillation in op-amp circuits?
[A] Too much or too/little feedback capacitance
[B] Excessive capacitive load on the output
[C] Oscillation of the power supply
[D] All of the above
(4)Which Operational Amplifier Circuit has the highest impedance?
[A]Summing Amp
[B]Precision Current Source
[C]Unity-Gain Buffer
[D]Photodiode Amplifier  答 1: ::(5)How do you get R1/R2 = R3/R4?

[A]  Buy expensive resistors at 0.001%
[B] Buy expensive matched resistors at 0.001%
[C] Trim with POT
[D] Place a capacitor between R3 and R4  答 2: ;;(6) How CAN you improve the noise and stability of this circuit?

[A]  Add a small amount of Cf in parallel with R1, Cf = 1/50 x C1
[B]   Add a large amount of Cf in parallel wth R1
[C]  Add a small amount of Rin in series with C1, about 1/20 x Rf
[D]  Both A and C  答 3: ;;
(7) What kind of theoretical operational amplifier circuit is shown below?

[A] Differentiator
[B]  Low-pass Filter
[C]  Integrator
[D] Non-Inverting  答 4: ;;
(8) In the circuit below, when is it important to make R5=R1||R2||R3||R4?


[A]When R5 is very large
When Ib is large
[C] When R5 x Ib is large
[D] When VS is large

[b](9) What are the reason(s) why the circuit below is only a theoretical circuit?


[A] Stability Problems
[B] Noise Problems
[C] Thermal shut down
[D] A and B  答 5: 关注模拟基础知识，大家来练练。 答 6: 楼主要是以为这些就是“模拟基础知识”那就错了。
这些仅是模拟电路知识的很小一部分。
答 7: 相信他不会局限于此吧？ 答 8: 可惜我连这些都没完全搞懂！ 答 9: 应该算是基础了只要运放掌握好，模拟就不怕了。
可惜我还是不了解运放。 答 10: 只能回答几题，还请多多指教 答 11: 只晓得第一题的答案是D。 答 12: 我做的答案D、D、D、B、C、D、A、D、D、
有些是猜的。