Title of the experiment: N Scheme Common Base transistor output characteristics.
AIM:
To simulate Common Base transistor output characteristics.
Facilities/material required:
| 1 | MULTISIM Software Loaded PC | 1 |
| 2 | Printer | 1 |
THEORY:
The transistor is a semiconductor device which transfers a weak signal from low resistance circuit to high resistance circuit. The words trans mean transfer property and istor mean resistance property offered to the junctions.
| Steps | Description (in full) |
| 1 | Theory |
| 2 | Transistor Symbol |
| 3 | Design Circuit |
| 4 | Simulation Procedure |
| 5 | Output Waveform |
ZENER DIODE SYMBOL:
CIRCUIT DESIGN:
Simulation Procedure:
- Open MULTISIM software.
- Design1 – Multisim file will be opened. Save it as Output characteristics of PNP transistor.
- Select PNP from the real components list and place it in the working area.
- Select DC power sources, DC current and ground from the same list and make connections as in the circuit.
- As seen in the above characteristics, the range of voltage for VBE is to be set at 0 – 10 V in steps of 2V and range of voltage for VBE is to be set at 0 – 10 in steps of 2V.
- For this, select Simulate => Analyses => DC sweep.
- In the DC Sweep Analysis, select Analysis Parameters. For VBC, set the start value as 0, stop value as 10 and increment as 2V.
- Select Use Source2. Select VBE as Source2. For VBE, set the start value as 0, stop value as 12 and increment as 2V.
- After that specify the output variables Base current and collector current and click Add. Click Ok.
- To Simulate the circuit, select Simulate => Analyses => DC sweep and click simulate.
- The output characteristics of PNP transistor is displayed. In the grapher view as below, to change the labels of left axis and right axis, double click on it and change the labels as required.
Result:
Thus the circuit is designed to simulate the VI characteristics of PNP transistor and the output graph is printed.
DC ANALYSIS SETTINGS:
DC ANALYSIS SETTINGS:
Questions with answers:
1.Explain about the Common Base configuration?
In a common base configuration, the base terminal is common between the input and output circuits. The applied input signal is fed to the emitter-base terminal and the output is collected from the collector-base terminal.
2. Mention about the different configurations of a transistor?
The different configurations of a transistor are common emitter configuration, common base and common collector configurations.
3. How a transistor performs as an electronic switch?
It is a well known fact that transistor is commonly used as switch in electronic circuits. We know that, when transistor is in cut off region, it works as off switch (off state condition) and when transistor is in saturation region, it works as on switch (on state condition).
4. Give the comparison and applications of a CE, CB and CC amplifiers?
| Property | CB | CE | CC |
| I/P resistance | Low | Moderate | High |
| O/P resistance | High | Moderate | Low |
| Current Gain | 1 | High | High |
| Voltage Gain | ≈150 | ≈ 500 | >1 |
| Phase Shift | 0 or 360° | 180° | 0 or 360° |
| Uses | High freq ckts | Audio freq ckts | For Impedance Matching |
Video Tutorial:
All experiments should be designed and verified through simulation tools like Multisim.
1. Zener diode (Forward and Reverse bias characteristics)
2. Rectifier circuits ( Half wave, Full wave, Bridge rectifier with filters)
3. Power supply with Zener diode as Regulator
4. Common Base transistor output characteristics
5. Common emitter amplifier (Implementation of Current Series negative feedback)
6. Emitter follower (Implementation of Voltage Series negative feedback)
7. RC Coupled amplifier (Implementation of the concept of multistage amplifier)
8. Clippers and Clampers
9. RC Phase shift oscillator (Medium frequency Sine wave generators)
10. Hartley oscillator (High frequency Sine wave generator)
11. Astable Multivibrator (Square or Rectangular wave generator)
12. Gate triggering of SCR with various gate currents.
