Q1: Consider the amplifier circuit shown below in Fig. 1 using BJTS with equal ß-200 (15 marks). V+ (6 to 20V) C1 10μ FO

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Q1: Consider the amplifier circuit shown below in Fig. 1 using BJTS with equal ß-200 (15 marks). V+ (6 to 20V) C1 10μ FOR In R1 2k2 R4 470k Q1 2N3904 R3 4k7 R2 4k7 ,C2 47μ Q2 2N3906 OH C3 10μ Out 1777 0V Fig. 1 1. Perform DC analysis to find the operating points of the 2 transistors (Vc le) (5 marks) 2. Calculate the small-signal voltage gain (Vout/Vin) (4 marks) 3. State what is true and what is false in the following. You must explain your answer (6 marks) a. If the BJT transistors are replaced by MOS transistors, the overall gain of the amplifier in Fig. 1 remains un-changed. b. C2 is a DC coupling capacitor. c. The second-stage in Fig. 1 is a common-collector amplifier. d. An ideal op amp is a differential amplifier with voltage gain=. Practically, cascaded multi-stages are needed to achieve this gain. e. The bandwidth of an amplifier is mainly determined by its high cutoff frequency. f. A differential amplifier is usually biased by a DC current source which is considered short circuit in the AC analysis.