Design lumped lc matching networks and compare to 2 5

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3) Design lumped LC matching networks and compare to (2).
5 Problem 4 Using this MOSFET model: a) Simulate S21, S11, S22 in dB magnitude vs. Frequency b) Design and place a 100 GHz lumped LC matcing networks at the input, and again Simulate S21, S11, S22 in dB magnitude vs. Frequency c) Keeping the input matching network in place, design and place a 100 GHz lumped LC matcing network at the output, and again Simulate S21, S11, S22 in dB magnitude vs. Frequency. d) We now increase C3 (Cgd) to 0.5 fF. Re-adjust the matching networks to obtain matched S11 and S22 at 100 GHz. What do you observe ? e) Increase Cgd to 5 fF and reduce Rg to 5 Ohms. Try to re-adjust the matching networks to obtain matched S11 and S22 at 100 GHz. Now what do you observe ?
6 Problem 5 Using the MSUB parameters of problems(1,2), design a quarter-wave line output matching network at 100 GHz. At the input, use a short-circuited high-impedance shunt line of 5 microns width to make the input impedance pure real, and then a quarter-wave series line to complete the input match.
7 The problems below use the ADS directory ADS_for_218a; this is on the class web site. Problem 6: a) Design matching networks to match the input and output to 50 Ohms at 100 GHz. Give values of all 4 elements. b) Simulate using the provided gain_testbench, and make plots of dB magnitude of all 4 S-parameters vs frequency (DC-300 GHz) on a linear frequency scale. Also make ADS Smith chart plots of S11 and S22 Ri=10 3.3 Ohms, gm=300100 mS, Rds=60 200 Ohms, Cgs=200 50 fF, Cgd=0 fF
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