Figure 1 illustrates a common emitter amplifier using BC547. Calculate the resistance of R1, R2, Rc and Re to make an emitter current of about 1 milli-amp by using the design notes below.

The voltage gain, input and output resistance of the amplifier can be predicted from the AC equivalent circuit of the amplifier. Use the developed the AC equivalent circuit below to work out the the voltage gain, and input and output resistance. Choose the correct calculations for them from the following options. Ignore the output resistor r₀ of the BJT and assume thermal voltage of the BJT is 25 mV.

The Figure below shows a BJT common collector amplifier as well as its AC equivalent circuit. Assume the R_S of the FG is 50Ω, early voltage of the BJT is 45V, current gain β is 100, thermal voltage V_T is 25mV, and biasing DC current I_C=1mA. Calculate r₀, r_π, and further input and output resistances R_in and R_out illustrated in the equivalent circuit. Which answers below are correct?

 

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Figure i illustrates a common emitter amplifler using BCS47. Calculate the resistance of R1, R2, Re and Re to make an emitter curent of about I milli-amp by using the design notes below. Vo Ge Design Noter • Aim for about l10% of VCC across Re. Then choose an E12 resistor value for Re to set the emimer current to ImA. • As the emiter sesistor Re takes 10% of Vec, the base volhage needs to be at about 2.7 volts to make the BJT operate in conduction mode. · Ensure that the curent flow through the voltage divider Ri and R2 is at least 10 times of the base current (which also flows through resistoe RI) as this tends to minimize the possibility that the base curent (uhen varying with AC) will affeet the biasing amangement. Assume the current gain Bof BCS47 is 100. • Make VCE sbout the same as the voltage drop acros Re for a largest output swing Which can be possible correet answers in the following options based on your design caleulations? RI-1SI, R2-27 ka, Re-, Re2 ka RI-IRO, R2-a. Re-22 ka Re-0 OB RI-22. R2-33 AO. Re-22. Re-10 k Ri-O, R2-27 R. Re- , Re82 ka. RI-1ONI. R2-27 LO, Re-1, Re-t0 OD. DE Figure i illustrates a common emitter amplifler using BCS47. Calculate the resistance of R1, R2, Re and Re to make an emitter curent of about I milli-amp by using the design notes below. Vo Ge Design Noter • Aim for about l10% of VCC across Re. Then choose an E12 resistor value for Re to set the emimer current to ImA. • As the emiter sesistor Re takes 10% of Vec, the base volhage needs to be at about 2.7 volts to make the BJT operate in conduction mode. · Ensure that the curent flow through the voltage divider Ri and R2 is at least 10 times of the base current (which also flows through resistoe RI) as this tends to minimize the possibility that the base curent (uhen varying with AC) will affeet the biasing amangement. Assume the current gain Bof BCS47 is 100. • Make VCE sbout the same as the voltage drop acros Re for a largest output swing Which can be possible correet answers in the following options based on your design caleulations? RI-1SI, R2-27 ka, Re-, Re2 ka RI-IRO, R2-a. Re-22 ka Re-0 OB RI-22. R2-33 AO. Re-22. Re-10 k Ri-O, R2-27 R. Re- , Re82 ka. RI-1ONI. R2-27 LO, Re-1, Re-t0 OD. DE

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1 Find the emitter voltage 10 VE 20x 100 2 V Find re... View the full answer