Using the theory covered at the module develop a common emitter amplifier circuit using mutism and a BC109 transistor to achieve gain of -100Simulate the circuit using multisimShow and explain your im

To design a common emitter amplifier circuit using a BC109 transistor to achieve a gain of -100, we can follow these steps:

1. Determine the desired gain: In this case, the desired gain is -100.

2. Calculate the required collector resistor (Rc): The collector resistor determines the gain of the amplifier. The formula to calculate Rc is Rc = Vcc / Ic, where Vcc is the supply voltage and Ic is the collector current. Let's assume Vcc = 12V. Since the BC109 transistor typically has a collector current of around 10mA, we can use this value to calculate Rc: Rc = 12V / 0.01A = 1.2kΩ.

3. Calculate the required base resistor (Rb): The base resistor determines the biasing of the transistor. The formula to calculate Rb is Rb = (Vcc - Vbe) / Ib, where Vbe is the base-emitter voltage and Ib is the base current. Let's assume Vbe = 0.7V and Ib = 0.01mA. Using these values, we can calculate Rb: Rb = (12V - 0.7V) / 0.01mA = 1130Ω. We can use a standard resistor value of 1.2kΩ for Rb.

4. Calculate the required input coupling capacitor (Cin): The input coupling capacitor blocks the DC bias from the input signal. The formula to calculate Cin is Cin = 1 / (2πf * R1), where f is the lowest frequency of interest and R1 is the value of the input resistor. Let's assume f = 20Hz and R1 = 1kΩ. Using these values, we can calculate Cin: Cin = 1 / (2π * 20Hz * 1kΩ) = 7.96μF. We can use a standard capacitor value of 10μF for Cin.

5. Choose suitable components: Based on the calculations above, we can choose the following components for the circuit:

• BC109 transistor
• 1.2kΩ collector resistor (Rc)
• 1.2kΩ base resistor (Rb)
• 1kΩ input resistor (R1)
• 10μF input coupling capacitor (Cin)

Once we have the components, we can simulate the circuit using Multisim.

The implementation of the circuit in Multisim would involve connecting the components as per the circuit diagram for a common emitter amplifier. The input signal (sinusoidal) would be connected to the input resistor (R1) via the input coupling capacitor (Cin). The output would be taken from the collector resistor (Rc). The base resistor (Rb) would be connected between the base of the transistor and the biasing voltage (Vcc). The emitter of the transistor would be connected to the ground.

After simulating the circuit in Multisim, we can measure the following parameters:

• Traces for input and amplifier output: These traces would show the input sinusoidal signal and the amplified output. The oscilloscope scale can be adjusted to clearly visualize the signals.

• Voltage drops: We can measure and display the voltage drops across the collector, emitter, R1, R2, and the collector-emitter voltage. These measurements would give us insight into the biasing and operation of the circuit.

• Currents: We can measure and display the currents at the collector, emitter, R1, R2, and the collector-emitter voltage. These measurements would help us understand the current flow and biasing conditions in the circuit.

• Frequency response: We can simulate the frequency response of the circuit using the bode plotter in Multisim. By varying the frequency and measuring the gain, we can plot a bode plot that shows the response of the amplifier at different frequencies. We should choose a suitable range of frequencies that includes both the lower and upper cutoff frequencies to analyze the behavior of the circuit.

Please note that the specific measurements and results would depend on the values chosen for the components and the simulation setup in Multisim