9.

1.(20%) Figure 1 shows the CS amplifier. The threshold voltage of transistor is -0.5 V. (a) Select a value for Rs to bias the transistor at ID = 0.4 mA and IVovl = 0.4 V. Assume Vsig to have a zero DC component. (b) Select value for Ro that results in vo/vsig = -8 V/V. (c) Find the largest sinusoid Voie peak that the amplifier can handle while remaining in the saturation region. (d) If to obtain reasonably linear operation, Vsig peak is limited to 40 mV, what value can RD be increased to while maintaining saturation-region operation? (5%*4)

2.(20%) Figure 2 shows the differential amplifier. Please find (a) the differential gain, (b) the differential input resistance, (c) the common-mode gain assuming the resistance Rc have 2% tolerance, and (d) the common-mode input resistance. For these transistors, β = 100, thermal voltage is 25.9 mV and Early voltage VA = 100 V. (5%*4)

3. (25%) Figure 3 shows a three-stage amplifier. (a) Find the DC bias collector current in each of the three transistors and DC bias output voltage Vo. Assume IVBEl = 0.7 V, β = 100, thermal voltage is 25.9 mV and neglect the Early effect for all BJTs. (b) Find the input resistance Rin, output resistance Rout, and voltage gain vo/vi. (10%, 5%*3)

4.(20%) For the CC-CB amplifier of Figure 4, let I = 1 mA, β = 100, Cπ= 8 pF, Cμ = 3 pF,Rig = 15 kΩ, RL= 20 kΩ, and thermal voltage is 25.9 mV. Find (a) the low-frequency overall voltage gain AM, (b) the frequencies of the poles for the high frequency response, and (c) the 3-dB frequency fi. All BJIs have the same β, Cπ and Cμ. (5%, 10%, 5%)

5. (15%) Please only use the diode and capacitor components to draw the circuits of peak rectifier, DC restorer and voltage doubler to come out the stable output voitage: (a) -Va, (b) -Va+ Va sin(ωt), (c) -2Va, with a stable sinusoid input voltage Va sin(ωt) as shown in Figure 5. (5%*3)

Dielectric constant: Si = 11.9 ; SiO2 =3.9. Bandgap: Si = 1.12 eV ; GaAs = 1.42 eV. 1. A silicon sample has a doping profile with donors ND = NO exp(-mx). If ND >>ni, find the expression for the built-in electric field at equilibrium. (20%)

2. A Si p-n junction has same doping concentration cm' in each side. The peak electric filed in the junction at breakdown is 2 x 105VIcm. Calculate the reverse breakdown voltage of this junction at 300K. (20%)

3. Calculate the oxide capacitance, the flatband capacitance, and the high frequency capacitance in inversion of a silicon MOS capacitor with a substrate doping ，a 25 nm thick silicon dioxide and an aluminum gate (ΦM = 4.1 V). (20%)

4. For heterojunctions in the GaAs-AlGaAs system, the direct bandgap difference is accommodated approximately in the conduction band and in the valence band. The bandgap of AlGaAs is 1.85 eV if Al composition is 0.3. Draw the band diagrams of two heterojunctions: (a)As on n-GaAs (b)As on n-GaAs (20%)

5. In a metal-Si Schottky barrier contact, the barrier height is 0.85 eV and the effective Richardson constant is 110 A/K2-cm2 . Calculate the ratio of the injected hole current to the electron current at 300K. Dp = 12 cm2/s, τp = s, and (20%)

109年 - 108 國立中山大學_碩士班招生考試_電機系(丙組)：離散數學#110538

109年 - 109 國立中山大學_碩士班招生考試_電機系(丙組)：離散數學#106106

107年 - 107 國立中山大學_碩士班招生考試_電機系(丙組)：離散數學#110222

106年 - 106 國立中山大學_碩士班招生考試_電機系(丙組)：離散數學#109065

102年 - 102 國立中山大學_碩士班招生考試_電機系(丙組)：離散數學#108985