* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Lab 10 - ece.unm.edu
Tektronix analog oscilloscopes wikipedia , lookup
Integrating ADC wikipedia , lookup
Loudspeaker wikipedia , lookup
Superheterodyne receiver wikipedia , lookup
Analog-to-digital converter wikipedia , lookup
Surge protector wikipedia , lookup
Audio crossover wikipedia , lookup
Oscilloscope types wikipedia , lookup
Power MOSFET wikipedia , lookup
Cellular repeater wikipedia , lookup
Scattering parameters wikipedia , lookup
Negative feedback wikipedia , lookup
Oscilloscope history wikipedia , lookup
Transistor–transistor logic wikipedia , lookup
Index of electronics articles wikipedia , lookup
Power electronics wikipedia , lookup
Schmitt trigger wikipedia , lookup
Regenerative circuit wikipedia , lookup
Current source wikipedia , lookup
Nominal impedance wikipedia , lookup
Switched-mode power supply wikipedia , lookup
Audio power wikipedia , lookup
Wilson current mirror wikipedia , lookup
Standing wave ratio wikipedia , lookup
Two-port network wikipedia , lookup
Current mirror wikipedia , lookup
Resistive opto-isolator wikipedia , lookup
Radio transmitter design wikipedia , lookup
Wien bridge oscillator wikipedia , lookup
Zobel network wikipedia , lookup
Operational amplifier wikipedia , lookup
Opto-isolator wikipedia , lookup
Project 10 Common Collector Amplifier Objective: This project will show the biasing, gain, frequency response, and impedance properties of a common collector amplifier. Components: 2N2222 BJT Introduction: The common collector amplifier as shown in Figure 10-1 is one of the most useful small-signal amplifier configurations. The same biasing scheme and frequency response approximation technique as used for the common emitter amplifier can also be used for the common collector amplifier. The only change that needs to be made in biasing is that the voltage across the emitter resistor RE is usually larger for the common collector to allow a greater output voltage swing. The collector resistor is also usually omitted in the common collector configuration. The main characteristics of the common collector amplifier are high input impedance, low output impedance, less than unity voltage gain, and high current gain. This amplifier is most often used as a buffer or isolation amplifier to connect a high impedance source to a low impedance load without loss of signal. The load seen by the amplifier's signal source is the input impedance of the amplifier. With a high input impedance, the CC amplifier loads the source very lightly. Therefore the signal source is largely isolated + 1. This high current gain allows the CC amplifier to increase the power of the signal. These power and current gains make the CC amplifier a practical choice as an output stage amplifier driving several devices and/or low impedance loads. Design: Design a common collector amplifier with the following specifications: 1. use a 2N2222 BJT and a 12 volt DC supply 2. midband gain VO/VS 3. low cutoff frequency FL between 100 Hz and 200 Hz 5. VO 6. load resistor RL 7. source resistance RS - p) Figure 10 - 1: Common Collector Amplifier Lab Procedure: 1. Construct the CC amplifier of Figure 10-1. Remember RS is installed in addition to the internal 50 resistance of the function generator. Verify the amplifier operation by measuring the Q-point and midband voltage gain. Monitor the output on the oscilloscope to make sure the waveform is not clipped. Note any distortion in the output signal. 2. Adjust the input signal level to get a 3.0 volt peak symmetric output voltage swing. 3. Determine the midband current gain IL/IS [measure IS by looking at the current through RS] What is the overall power gain? 4. Observe the loading affect by replacing RL first by the output signal and comment on the loading affect. 5. Use computer control to record and plot the frequency response. Find the corner frequencies and bandwidth to verify that the specifications have been met. 6. Measure the input impedance seen by the source [look at the current through RS and the node voltage on the transistor side of RS] and the output impedance seen by the load resistor [look at the open circuit voltage and the current through and voltage across RL]. Verify that the input impedance specification has been met. Questions: 1. How can you achieve maximum power transfer from the input signal source to the amplifier circuit? Is the load resistance a factor in the answer? 2. What value of load resistance results in maximum voltage gain? What load resistance results in maximum power transfer to the load? +1. Comment on any differences. 4. Compare the measurements in Lab Procedures 1-6 to the theoretical predictions such as those obtained using PSPICE®. Note that you must adjust the circuit file to determine the output impedance. 5. What other method could be used to measure RO?