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Lab 7

Lab #7

BJT TRANSISTOR

1. OBJECTIVES:

To become familiar with the basic properties of the Bipolar Junction Transistor (BJT).  To analyze all three currents related to the BJT and focus on 2 main voltages of the BJT including (Vce and Vbe).  To compute the current and voltage gains.  To perform DC and AC analysis.

2. COMPONENTS USED AND SPECIFICATION:

– 2N2222 NPN transistor

– Several Resistors

– DC power supply

– Multimeter for voltage and current readings

– Waveform generator

– Oscilloscope with probes

– Computer with Multisim software for computer simulations

– Wire, alligator clips, and a breadboard

3. DC Analysis:

lab 7_1

Figure 1

a) Calculate the DC analysis values for the circuit shown in Figure 1.  Find IC, IE, IB, Rth, Vth, VE, VC, and VB.  β =    100, VA = 100 and VBE = 0.7 volts .

b) Assemble the circuit as shown in Figure 1 (R1= 27KΩ, R2= 15KΩ, RC= 2.2KΩ, RE= 1.2KΩ, VDC= 9V) and take measurements to verify calculations (both software simulation and hardware).

4. AC Analysis:

lab 7_2

Figure 2

a) Calculate the AC analysis values using the T-Model shown in Figure 2.  Find RIN, ROUT, ro, re, Avo, Av, and Gv

b) Assemble the circuit as shown in Figure 1 (Rsig= 10KΩ, R1= 27KΩ, R2= 15KΩ, RC= 2.2KΩ, RE= 1.2KΩ, RL= 2.2KΩ, VDC= 9V, and all capacitors are very large) and take measurements to verify calculations (both software simulation and hardware). Set the sine wave generator to 50mVpp (limitation of generator) and 1KHz. Explain the discrepancy, if the measured gains are not within ± 0% of the calculated gains.

Lab report is individual and Analysis part should be on your own words.

The Lab report must include all lab procedures, all the observations from hardware and software simulations, and a detailed analysis.

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