# Basic Electronic and DLD Important Questions – Past Papers

## Paper 1: Basic Electronic DLD – University Past Papers.

Time Allowed: 3 hours

Total Marks:    70, Passing Marks (35)

Q.1 Fill in the blanks [14 Marks]
a. The Component having the ability to store Electric Charges is known as —————————-
b. The Unit of Voltage is _¬¬¬¬¬¬______.
c. The__________is the same at all points in a Series circuit.
d. Naturally Pure Semiconductor is known as —————————————.
e. FET is a —————————————————– control Device.
f. The reciprocal of Frequency is called —————————————————–.
g. An Practical Current Source has a _¬¬¬¬¬¬______ resistance.
h. The Current divider Technique is only used in _¬¬¬¬¬¬______ circuits.
i. (1111)2 = (——–)16
j. 1’s compliment of (1011 1110)2 ———————————).
k. The Gray code of 10101101 is………………………………..
l. If all inputs of NAND-Gate are zero then the output of the NAND-Gate………………
m. RAM is ……………………………………….Memory

n. Half Adder accept two Inputs and Produce ……………………….Outputs.

Q.2. (a) Define Resistor, Capacitor and Inductor.
(b) Explain Ohm’s Law in detail. (6+8)

Q.3. (a) Briefly explain the Intrinsic and Extrinsic Semiconductor in detail.
(b) Differentiate PNP and NPN Transistor? (7+7)

Q.4. (a) Explain the Kirchhoff’s Voltage Law and Kirchhoff’s Current Law.
(b)Write down the general Statement of Superposition, s Theorem. (7+7)
Q.5. (a) Simplify the given expression using Boolean rules and/or Demorgan’s theorem.
A (A + B) + (B + AA) (A + B)

(b) Draw the logic Circuit of the given SOP and POS expressions
(1) (2)
(7+7)
Q.6 Briefly Explain the function of Full Adder with the help of logic Circuit and Truth Table.
. (14)
Q.7 Define Multiplexer .Design and Explain 8 to 1 Line Multiplexer. (7+7)

Q.8. Write short notes on any TWO of the following.
(a) Encoder & Decoder (b) PN Junction Diode Application (c) RAM & ROM (7+7+7)

## Paper 2: Basic Electronic DLD – University Past Papers.

Time Allowed: 3 hours

Total Marks:    70, Passing Marks (35)

Q.1 Fill in the blanks [14 Marks]

1. The Material having large no of free electrons and current can easily flow in them is known as —-.
2. A Watt is unit of _¬¬¬¬¬¬______.
3. The__________is the same at all points in a parallel circuit.
4. Naturally Pure Semiconductor is known as —————————————.
5. BJT is a —————————————————– control Device.
6. The reciprocal of time period is called —————————————————–.
7. An Ideal Current Source has a _¬¬¬¬¬¬______ resistance.
8. The Voltage divider Technique is only used in _¬¬¬¬¬¬______ circuits.
9. (1111111)2 = (——–)8
10. 2’s compliment of (1011 1110)2 ———————————) .
11. The Gray code of 10101101 is………………………………..
12. If all inputs of NOR-Gate are zero then the output of the NOR-Gate………………
13. Rom is ……………………………………….Memory

Q.2. (a) Define Resistor, Capacitor and Inductor. (6+8)
(b)Differentiate Conductor, Insulator and Semiconductor with the help of Energy band Diagram
Q.3. (a) Briefly explain the Intrinsic and Extrinsic Semiconductor in detail.
(b) Differentiate BJT and FET? (7+7)
Q.4. (a) Explain the Voltage Divider and Current Divider Technique.
(b)Write down the general Statement of Thevenin, s Theorem. (7+7)
Q.5. (a) Simplify the given expression using Boolean rules and/or Demorgan’s theorem. (7+7)
A (A + B) + (B + AA) (A + B)
(b) Draw the logic Circuit of the given SOP and POS expressions
(1) (2)
Q.6 Briefly Explain the function of 3 to 8 Line Decoder with the help of logic Circuit and Truth Table.

. (14)
Q.7 Differentiate between Encoder & Decoder. Design 1-8 Lines De-Multiplexer. (7+7)

Q.8. Write short notes on any TWO of the following.
(a) JK Flip Flop (b) PN Junction Diode (c)Digital Registers (7+7)

Prof.Fazal Rehman Shamil (Available for Professional Discussions)
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