110年 - 110 國立中山大學碩士暨碩士專班招生考試_電機系碩士班/甲組:電子學(甲組)#104341

1.(20pt) Figure 1 is a summing op-amplifier to produce the output v₀ = -10v₁ -4v₂+5v₃ + 2v₄・ The resistors R₁ = 20 kΩ and R₃ = 80 kΩ. The op-amplifier is ideal. Please determine the values of resistors R₂, R₄, R₅ and R₆. (5pt*4)

2.(30pt) For the circuit shown in Figure 2, the transistor parameters of Q₁ and Q₂ are: = 1.2 V, = 1.6 mA/V², and neglect channel length modulation effect. Let R₁ + R₂ + R₃ = 300 kΩ and Rs = 10 kΩ. = 5 V, -Vs =-5 V. (a) Please determine the R₁, R₂, R₃ and R_D such that DC current I_D = 0.4 mA and DC voltage Coupling capacitor Cc is large enough that can be treated as short circuit for AC analysis. Please also find the voltage gain of small signal. (5pt*6)

3.(25pt) The circuit configuration to be designed is shown in Figure 3 and the = -40. Assumingβ = 100, 0.7 V, and neglect Early effect. Thermal voltage V_T = 26 mV. Please find the value of = 4 V and I_E = 0.2 mA. And calculate the corresponding values of the AC voltage gain input resistance . Coupling capacitor Cc is large enough that can be treated as short circuit for AC analysis. (5pt*5)

4.(25pt) For the circuit shown in Figure 4, the parameters are: = 0.1 kΩ, R₁ = 40 kΩ, R₂ = 5.72 kΩ, R_E = 0.5 kΩ, Rc = 5 kΩ, and R_L = 10 kΩ. The transistor parameters are: β = 150,  0.7 V, neglect Early effect, Cπ = 35 pF, Cμ = 4 pF, Cc= 1 μF. Thermal voltage V_T = 26 mV. Please determine the lower and upper corner frequency (f_L and f_H), midband gain. (10pt, 10pt, 5pt)