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## Intermediate / 1 to 5 years experienced level questions & answers

### Ques 1. What is the difference between combinational and sequential circuits?

Combinational circuits have no memory, while sequential circuits have memory elements.

### Ques 2. Differentiate between synchronous and asynchronous counters.

Synchronous counters use a common clock signal for all flip-flops, while asynchronous counters do not.

### Ques 3. Explain the working principle of a shift register.

A shift register is a cascade of flip-flops where the data is shifted through the register in one direction.

### Ques 4. What is the significance of Karnaugh maps in digital design?

Karnaugh maps are used for simplifying Boolean expressions and optimizing digital circuits.

### Ques 5. Describe the operation of a D-type flip-flop.

A D-type flip-flop changes its output state based on the input signal and the clock signal.

### Ques 6. What is a multiplexer and how is it different from a demultiplexer?

A multiplexer selects one input from multiple sources, while a demultiplexer directs one input to multiple outputs.

### Ques 7. Define the terms 'complement' and 'comparator' in digital electronics.

'Complement' refers to the inversion of a binary number, while a 'comparator' is a device that compares two numbers.

### Ques 8. What is the significance of Moore and Mealy machines in digital design?

Moore and Mealy machines are models of finite state machines used in digital systems.

### Ques 9. How does a counter differ from a shift register?

A counter is designed to count clock pulses and produce an output based on the count, while a shift register is used for serial data shifting.

### Ques 10. Explain the concept of synchronous reset in flip-flops.

A synchronous reset ensures that the flip-flop is reset only when the clock signal is active.

### Ques 11. How does a multiplexer function as a data selector?

A multiplexer selects one data input from multiple sources based on the control inputs.

### Ques 12. Define the terms 'fan-out' and 'fan-in' in digital systems.

'Fan-out' is the number of standard loads a gate can drive, while 'fan-in' is the number of inputs to a gate.

### Ques 13. Explain the working principle of a JK flip-flop.

A JK flip-flop toggles its output state based on the inputs and the clock signal.

### Ques 14. What is the purpose of a multiplexer in a data bus system?

In a data bus system, a multiplexer is used to select one of several data inputs and route it to the bus.

### Ques 15. Differentiate between a latch and a flip-flop.

Latches are level-sensitive and can change output state as long as the clock input is active. Flip-flops are edge-sensitive and change state only on the rising or falling edge of the clock signal.

### Ques 16. What is the significance of Gray code in digital systems?

Gray code is a binary numeral system where two successive values differ in only one bit. It is used in applications where a single bit change should result in a small change in the system state.

### Ques 17. Explain the operation of a 4-bit binary ripple counter.

A 4-bit binary ripple counter consists of four flip-flops, each toggling on the falling edge of the previous flip-flop's output. The output forms a binary count sequence.

### Ques 18. What is the purpose of a digital multiplexer in communication systems?

In communication systems, a digital multiplexer combines multiple input signals into a single output signal for transmission over a shared medium.

### Ques 19. What is the role of a digital comparator in microprocessor applications?

In microprocessor applications, a digital comparator is used to compare two binary numbers and determine their relationship, such as equality or magnitude.