Electronics and Communication Engineering - Electronic Devices and Circuits

41.
The total number of input words for 4 input OR gate is
20
16
12
8
Answer: Option
Explanation:

24 = 16.


42.
In digital circuits Schottky transistors are preferred over normal transistors because of their
lower propagation delay
lower power dissipation
higher propagation delay
higher power dissipation
Answer: Option
Explanation:

Schottky transistors have low switching time and hence low propagation delay.


43.
A flip flop is a
combinational circuit
memory element
arithmetic element
memory or arithmetic element
Answer: Option
Explanation:

It is a memory element used in digital circuits.


44.
A 4 bit parallel type A/D converter uses a 6 volt reference. How many comparators are required and what is the resolution in volts?
0.375 V
15 V
4.5 V
10 V
Answer: Option
Explanation:

No. of comparators = 2n - 1 = 24 - 1 = 15

.


45.
Quantization error occurs in
D/A converter
A/D converter
both D/A and A/D converter
neither D/A nor A/D converter
Answer: Option
Explanation:

Analog input can have any value but digital value can have only 2N discrete levels (for N bits). Hence quantization error in A/D conversion.