Online Digital Electronics Test - Digital Electronics Test - Random

Instruction:

This is a FREE online test. Beware of scammers who ask for money to attend this test.
Total number of questions: 20.
Time allotted: 30 minutes.
Each question carries 1 mark; there are no negative marks.
DO NOT refresh the page.
All the best!

A periodic digital waveform has a pulse width (t_w) of 6 ms and a period (T) of 18 ms. The duty cycle is ________.

3.3%

33.3%

18%

[#]

Parallel transmission is faster than serial.

True

False

[#]

In binary, the decimal number 93 converts to ________ digits.

seven

eight

five

[#]

The gates in this figure are implemented using TTL logic. If the output of the inverter has an internal open circuit, what voltage would you expect to measure at the inverter's output?

Less than 0.4 V

1.6 V

Greater than 2.4 V

All of the above

[#]

Which of the following is an important feature of the sum-of-products (SOP) form of expression?

All logic circuits are reduced to nothing more than simple AND and OR gates.

The delay times are greatly reduced over other forms.

No signal must pass through more than two gates, not including inverters.

The maximum number of gates that any signal must pass through is reduced by a factor of two.

[#]

Implementing the expression using NAND logic, we get:

(A)

(B)

(C)

(D)

[#]

A NOR gate is a universal gate.

True

False

[#]

Which of the following combinations of logic gates can decode binary 1101?

One 4-input AND gate

One 4-input AND gate, one OR gate

One 4-input NAND gate, one inverter

One 4-input AND gate, one inverter

[#]

A good rule of thumb for determining the pin numbers of dual-in-line package IC chips would be to place the notch to your right and pin #1 will always be in the lower right corner.

True

False

[#]

10.

The action of ________ a FF or latch is also called resetting.

breaking

clearing

freeing

changing

[#]

11.

A 4-bit shift register that receives 4 bits of parallel data will shift to the ________ by ________ position(s) for each clock pulse.

right, one

right, two

left, one

left, three

[#]

12.

A counter has a specified sequence of states, but a shift register does not.

True

False

[#]

13.

Instructions for the 80X86 family are downward compatible.

True

False

[#]

14.

One can safely state that the output lines for a demultiplexer are under the direct control of the:

input data select lines.

the internal AND gates.

the internal OR gate.

Input data line.

[#]

15.

In HDL, one of the strategies used in strategic planning is to find the speed requirements.

True

False

[#]

16.

In the frequency counter, the length of time for the ________ to be enabled can be selected with the range select input.

display register

frequency prescaler

BCD counter

signal generator

[#]

17.

A diode placed in parallel across a relay coil serves what function?

to regulate input voltage

to protect the coil from arcing

to ensure most of the current passes through the coil

to reduce arcing across the relay contacts

[#]

18.

Show from the truth table how an exclusive-OR gate can be used to invert the data on one input if the other input is a special control function.

Using A as the control, when A = 0, X is the same as B. When A = 1, X is the same as B.

Using A as the control, when A = 0, X is the same as B. When A = 1, X is the inverse of B.

Using A as the control, when A = 0, X is the inverse of B. When A = 1, X is the same as B.

Using A as the control, when A = 0, X is the inverse of B. When A = 1, X is the inverse of B.

[#]

19.

A circuit that responds to a specific set of signals to produce a related digital signal output is called a(n):

BCD matrix

display driver

encoder

decoder

[#]

20.

Why is a decoupling capacitor needed for TTL ICs and where should it be connected?

to block dc, connect to input pins

to reduce noise, connect to input pins

to reduce the effects of noise, connect between power supply and ground

[#]

Quick links

Quantitative Aptitude

Verbal (English)

Reasoning

Programming

Interview

Placement Papers

Online Digital Electronics Test - Digital Electronics Test - Random

Marks : 2/20

Test Review : View answers and explanation for this test.

Current Affairs

Interview Questions

Group Discussions