Question

Q1. For the cascade amplifier circuit shown in Fig (1): a) What are the functions of the capacitors C, C2 and C3? And what are the functions of the capacitors Cs and CE? b) What are the functions of the resistors RD and Rc? c) Draw the DC biasing circuits for each stage. d) Find loa, VGsa, VDs and gm for the JFET stage (you may use either mathematical or graphical methods) e) Calculate l, Ic, le and Ve for the BJT circuit. f)Calculate the value of re for the BJT transistor. g) Draw the ac equivalent circuits of the multistage amplifier. h) Determine the voltage gain of the JFET circuit with the BJT amplifier as a load. i) Determine the input impedance Z and output impedance Zo of the overall amplifier circuit assuming that ra 50 k and ro 30 kQ Calculate the output voltage Vo if the input source voltage Vs is 2.0 mV with 500 source resistance (Rsig) k) Find the overall voltage gain Avs if the output (Vo) of the second stage is connected to a load resistance of Ru 1 k +12V RD 2k0 Rc 4.7kn 91kQ C, 0.1 F 10HF Va 065 μF =6 mA V. B-150 -3 V 15MO 12k0 100 HF 100 μF 1kn 3900 Figure (1) JFET, BJT cascade amplifier circuit ww

Answer 1

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LODP O39 Tos - VDs e- aDS 1Sost NGS 2.6 2.39 TDS a- 1 (G15 12- 23x 1 76 S76 9.GI ma) Oper ang poink JFET - (3r sa) BTT - biasin DC BTJ 4.3) MA 4. 3) M n IS0 O46 2 sS 4.3) xIG O. 65 mA