Page 100 - Physics - XII

16. With the help of variable voltage power supply, gradually, increase the applied voltage in steps and
note the corresponding voltmeter reading.

17. Continue increasing the voltage till the current reaches the maximum value of microammeter.
18. Plot a graph between V and I by taking them along negative X-axis and negative Y-axis, respectively.
R
R
This graph will give you the reverse bias characteristics of diode.
Observations
For Forward Biasing

p-n junction diode used (diode number) = _____
Range of voltmeter = ( _____ to _____) V
Least count of voltmeter scale = _____ V

Range of milliammeter = ( _____ to _____ ) mA
Least count of milliammeter scale = _____ mA

Table for Forward Bias Characteristics

S. No. Forward voltage, V (V) Forward current, I (mA)
F F
1.
2.
3.

10.

For Reverse Biasing
Range of voltmeter = ( _____ to _____ ) V

Least count of voltmeter scale = _____ V
Range of microammeter = ( _____ to _____ ) µA
Least count of microammeter scale = _____ µA

Table for Reverse Bias Characteristics

S. No. Reverse voltage, V (V) Reverse current, I (µA)
R R
1.
2.
3.

10.

Graph

1. Plot a graph between forward voltage (V ) along positive X-axis and forward current (I ) along the
F
F
positive Y-axis. Locate the knee and determine the threshold voltage. The point where the current starts
increasing suddenly is called knee point in the forward bias characteristic.

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