Before continuing the experiment, learners should know

• What is P-N junction diode and How it works?
• How is this experiment useful in real life? Click here

  PN junctions are versatile components with wide applications, for example AC-DC rectifiers, voltage regulators, signal processors, and light-to-electricity converters (photodiodes) or the reverse direction (LEDs). These are part of all areas covering electronics, power systems, and optoelectronics.Additionally, diodes are used to restrict reverse voltage. They will not permit high current to pass until the breakdown voltage is reached.

Aim:

To determine the volt-ampere characteristics of a silicon p-n junction diode.

Apparatuse Required:

Ciruit Diagram

Forward Bias:

Forward Bias:

1. Set up the circuit according to this circuit diagram for forward biasing a diode.

2. Keep in your mind that the positive terminal of the power supply shall be connected to anode of the diode and negative terminal to cathode.

3. Switch on the power supply.

4. Gradually increase the input voltage (supply voltage) in incremental steps.

5. Values at each step of voltage are recorded, which involve the values of -

* The current flowing through the diode

* The voltage across the diode

6. Take voltage on the x-axis and current on the y-axis

7. Plot the data points on the graph from the recorded data.

Reverse Bias:

1. Set up the circuit to reverse bias a diode, shown

2. Connect the cathode of the diode to the positive terminal on the RPS and connect the anode to the negative terminal.

3. Switch on the power supply.Since supply voltage is an input voltage, vary it in incremental steps.

4. For each step-up of the voltage measure the following: Current passed through the diode Voltage across diode

5. All read values are summarized in a tabular form where one column contains the voltage values and another columns the corresponding current values.

6. A graph is plotted with voltage on x-axis and current on the y-axis. The readings as taken by noting down the points are being plotted on this graph.

Forward Bias:

Reverse Bias:

1. Do not allow the current and voltage to exceed the diode ratings; otherwise, it will be damaged.

2. Ensure that the voltmeter and ammeter are connected according to the circuit diagram.

3. Check all circuit connections before powering the power supply.