BJT Amplifier Design
1. Given and Required Specifications
The design of the amplifier shall be performed for the Fairchild Q2N3904 NPN Transistor. Specifications can be obtained from the datasheet for the Fairchild Q2N3904 and are typically given in a variety of ways. Minimum and maximum operating conditions are found in a table at the beginning of the datasheet.
Regions of operation and performance characteristics are given in graphs toward the end of a datasheet. Spice models that contain useful parameters are included somewhere in the middle. Other datasheets may have circuit configurations, packing options, or physical drawings. Students will need to acquire P from the Current Gain (hfe) vs. Collector Current in the datasheet.
The early voltage can be found in the SPICE parameters under VAF. There may be other relevant information included on the datasheet needed for the project which will be responsibility of the student to determine.
Specifications for Amplifier:
- AV = VO/VI > 150 V/V
- RL = 5 K
- VCC = 16 V (rail voltage, single supply)
- Power Consumption = VCC * ICC < 200 mW
- Swing = 10 V pk to pk
- Rinput = any value
- Routput = any value Requirements for Project:
- Hand Analysis
¦ DC Biasing
¦ AC vs DC Load Line
¦ AC Gain
¦ Rinput
¦ Routput
- PSpice Simulation of Amplifier
¦ DC Biasing
¦ AC Gain
¦ Transient Response
¦ Rinput
¦ Routput
- Write a Technical Report in the form of IEEE Journal Publication
The IEEE Journal Publication style can be found on the IEEE website using the link below. The website includes resources for references, images, titling, and even templates that may be used to create the paper. The paper should include various sections such as:
- Introduction
- DC Analysis
- AC Analysis
- Results
- Areas for Future Research / Improvement
- Conclusion References
Results to Include
The plots and tables previously asked for during the tutorial should be included in the results section. Discussion about what is happening with the plot or table should be included. The following about the frequency response should also be included in the results section for both simulated and measured.
Range of frequency of operation: Hz to Hz 3dB Bandwidth of the circuit: Hz Peak Gain Frequency: Hz
Conclusion
A discussion of the circuit and how it performed should be included in the conclusion. The following questions should also be addressed: Why is there a difference between the hand calculated gain, the simulated gain, and the measured gain?
At what value does the swing become unsymmetrical and why is that? How did you approach solving this design problem (remember to write in passive voice)?