110年 - 110 國立臺灣大學_碩士班招生考試_生物機電工程學研究所丙組:電子學(B)#101163

(a) (5%) Derive the voltage gain,. What kind of amplifier is it?

(b) (5%) Derive the voltage gain, . What kind of amplifier is it?

(c) (5%) Using superposition, derive the relation of Vou and V₂-V₁ as a function of R₁, R₂, Rrand Rg.

(e) (10%) Determine the gain, , of the advanced version.

2. (10%) Design the current limiting resistance for a circuit (Fig. 3) with a LED (Forward Voltage, V_f= 3.5V, CurrentmA), a lithium-ion battery (Supply Voltage = 4. 1 V), and the Resistance. Specify the required resistance value and power rating of the resistance.

3. (20%) For the circuit in Fig. 4, find the range of v_l, over which Q_lis operating in saturation. Under such condition, find the output voltage. Assume the threshold voltage

4. (20%) Evaluate the voltages at all nodes and the currents through all branches in the circuit of Fig. 5. Assume β= 100. Please first mark all the nodes and the branch currents of Fig. S on the answer sheet.

5. (20%) A common- -source amplifier using an NMOS transistor biased in the manner of Fig. 6 for which gm = 2 mA/V is found to have an overall voltage gain G_v of -16 V/V. What value should a resistance Rs inserted in the source lead have to reduce the voltage gain by a factor of 4?