This document contains sample questions and solutions for a basic electronics course on diodes. It includes 6 questions about calculating diode currents and voltages given saturation currents, applied voltages, and temperatures. The questions cover both forward and reverse bias conditions. Dr. Piyush Charan of Integral University authored the document to provide open educational resources for understanding diode characteristics and basic diode circuit analysis.

1. for
Open Educational Resource
on
Basic Electronics (EC101)
by
Dr. Piyush Charan
Assistant Professor
Department of Electronics and Communication Engg.
Integral University, Lucknow
This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.

2.  Q1. A germanium diode has a reverse saturation current of 0.19µA. Find the current
in the diode when it is forward biased with 0.3V at 27°C.
20-Jan-21 Dr. Piyush Charan, Dept. of ECE, Integral University, Lucknow 2

3.  Q2. The forward current in a Silicon Diode is 15mA at 27°C. If reverse
saturation current is 0.24nA, what is the forward bias voltage?
20-Jan-21 Dr. Piyush Charan, Dept. of ECE, Integral University, Lucknow 3

4.  Q3. A silicon diode is reverse biased with 5V at room temperature. If
reverse saturation current is 60pA, what is the diode current?
20-Jan-21 Dr. Piyush Charan, Dept. of ECE, Integral University, Lucknow 4

5.  Q4. A germanium diode carries a current of 10mA when it is forward
biased with 0.2V at 27°C. (a) Find reverse saturation current. (b) Find the
bias voltage required to get a current of 100mA.
20-Jan-21 Dr. Piyush Charan, Dept. of ECE, Integral University, Lucknow
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6. 20-Jan-21 Dr. Piyush Charan, Dept. of ECE, Integral University, Lucknow 6

7.  Q5.Calculate the static and dynamic resistance of a P-N Junction diode,
when the applied voltage is 0.25V for Germanium Diode. I0 =1µA and
T=300K.
20-Jan-21 Dr. Piyush Charan, Dept. of ECE, Integral University, Lucknow 7

8. 20-Jan-21 Dr. Piyush Charan, Dept. of ECE, Integral University, Lucknow 8
For Static Resistance,
For Dynamic Resistance,

9.  Q6. A silicon diode has a saturation current of 1pA at 20°C. Determine (a)
Diode bias voltage when diode current is 3mA. (b) Diode bias current when
the temperature changes to 100°C, for the same bias voltage.
20-Jan-21 Dr. Piyush Charan, Dept. of ECE, Integral University, Lucknow 9

10. 20-Jan-21 Dr. Piyush Charan, Dept. of ECE, Integral University, Lucknow 10

11. Thanks!!!
20-Jan-21 Dr. Piyush Charan, Dept. of ECE, Integral University, Lucknow 11
Contact:
er.piyush.charan@gmail.com
piyush@iul.ac.in