103年 - 103 國立嘉義大學_碩士班招生考試試題_電機工程學系：電子學#146110

1. The BJTs in Fig. 1 have β = 100. Find VB and VE for Vi = +3Vand -10V, respectively. (16%, each sub-question takes 4%)

(a) indicate the operating region (3%), and

(b) calculate the base current IB, collector current IC and Vo (12%,Each sub-question takes 4%)

3.For the voltage divider with I = 90 μA, shown in Fig. 3, e MOSFET has V_T = 1V, μ_nCox = 20 μA/V², and neglect the effectof r_o. Design the W/L ratio of each Q₁, Q₂, and Q₃ MOSFETs suchthat the source voltage V₁ of the transistor Q₁ is +1 V and sourcevoltage V₂ of the transistor Q₂ is -1 V. (18%, Each sub-questiontakes 6 %)

(a) Find the values of R_E and R_C, such that I_E = 2 mA and V_BC =4.5 V. (12%, each sub-question takes 6 %)

(b) Find the values of I_E and V_BC when R_E = 3.9 kΩ and R_C = 2.2kΩ. (12%, Each sub-question takes 6 %)

(b) Find the values of I_E and V_BC when R_E = 3.9 kΩ and R_C = 2.2kΩ. (12%, Each sub-question takes 6 %)

5. Select a value for “RE” in Fig. 5 so that the transistor saturateswith a forced β of 30. Assume VEB = 0.7 V and VEC,sat = 0.2 V. (12%)

6. The design of a class AB MOS output stage, as shown in Fig. 6,is being considered, where each transistor has |Vt| = 1 V and μC_oxW/L = 300 mA/V².
What value of gate-to-gate bias voltage “V_GG” is required suchthat the incremental output resistance of the equivalent circuitin the quiescent state is 25 Ω? (15%)