Question

AIM: To draw the V-I Characteristic curves of silicon and germanium PN junction diodes APPARATUS REQUIRED: Breadboard, DC power supply - each 1 Resistor 1kÎ©, IN4004, 1N283, 5.6 V zener diode - each 1 Multimeters - 2 No. Connecting wires FORWARD BIAS CHARACTERISTICS CIRCUIT DIAGRAM XMM2 V XMM1 R WM 1kÎ© A - ANODE K - CATHODE A Variable DC Source 1N4004 - SILICON 1N283 - GERMANIUM PROCEDURE: I. Construct the circuit as shown. Care should be taken in connecting the polarities of multimeters (for measuring the current and the voltage) and the leads of the diode. It is important to note that, under forward bias, the positive terminal of the battery (+) should be connected to the anode of the diode and the negative terminal to the cathode. 2. Start with the zero value of the variable DC voltage source. Note the readings in the ammeter and voltmeter and enter into the tabular column. 3. Slowly increase the value of input voltage in the voltage source. Note down the ammeter readings corresponding to voltmeter readings starting from 0 Volt up to 1 Volt in steps of 0.1 Volt. You can observe that the current readings are in the order of mA. 4. Draw a graph between the voltage (in the X-axis) and the current (in the Y-axis) in the I quadrant. 5. Note down the cut-in voltage (also called threshold voltage) of the silicon diode IN4004. 6. Repeat the same procedure for the germanium diode (1N283) by varying the input DC voltage source in steps of 0.1 V up to IV. 7. Note down the corresponding ammeter and voltmeter readings. 8. Draw the graph as before. Find out the cut-in voltage from the graph.

AIM: To draw the V-I Characteristic curves of silicon and germanium PN junction diodes

APPARATUS REQUIRED: Breadboard, DC power supply - each 1 Resistor 1kÎ©, IN4004, 1N283, 5.6 V zener diode - each 1 Multimeters - 2 No. Connecting wires

FORWARD BIAS CHARACTERISTICS

CIRCUIT DIAGRAM

XMM2
V XMM1
R WM 1kÎ©
A - ANODE K - CATHODE
A
Variable DC Source
1N4004 - SILICON 1N283 - GERMANIUM

PROCEDURE:

I. Construct the circuit as shown. Care should be taken in connecting the polarities of multimeters (for measuring the current and the voltage) and the leads of the diode.

It is important to note that, under forward bias, the positive terminal of the battery (+) should be connected to the anode of the diode and the negative terminal to the cathode.

2. Start with the zero value of the variable DC voltage source. Note the readings in the ammeter and voltmeter and enter into the tabular column.

3. Slowly increase the value of input voltage in the voltage source. Note down the ammeter readings corresponding to voltmeter readings starting from 0 Volt up to 1 Volt in steps of 0.1 Volt. You can observe that the current readings are in the order of mA.

4. Draw a graph between the voltage (in the X-axis) and the current (in the Y-axis) in the I quadrant.

5. Note down the cut-in voltage (also called threshold voltage) of the silicon diode IN4004.

6. Repeat the same procedure for the germanium diode (1N283) by varying the input DC voltage source in steps of 0.1 V up to IV.

7. Note down the corresponding ammeter and voltmeter readings.

8. Draw the graph as before. Find out the cut-in voltage from the graph.