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1. What is Verilog?
Verilog is a hardware description language (HDL) that is used for designing digital circuits. It was developed at UC Berkeley in the late 1970’s by David A. Patterson and others. It is a general-purpose HDL designed for simulation and synthesis of electronic systems.
2. How does Verilog differ from VHDL?
VHDL is a special case of Verilog where the syntax is simplified. In particular, only two data types are supported: signed 8 bit integers and unsigned 32 bit fixed point numbers.
3. Why do we need Verilog?
The primary use of Verilog is to design digital circuits. However, it can also be used to simulate analog circuits, control software, and test equipment.
4. What is the difference between simulation and synthesis?
Simulation is the act of running a program written in Verilog to model a circuit. Synthesis is the act of turning a Verilog file into a netlist that can be used in a place & route tool.
5. What is a netlist?
A netlist is a list of components connected together to represent an electrical circuit.
6. What is a register transfer level (RTL)?
An RTL represents the behavior of a circuit at the register transfer level. An RTL consists of registers, combinational logic, and sequential elements.
7. What is a behavioral description?
A behavioral description describes how a circuit behaves. Behavioral descriptions often consist of state diagrams, flow charts, and pseudocode.
8. What does Verilog stand for?
The name stands for VEriLog-a Hardware Description Language. It was developed by Cadence Design Systems Inc. (Cadence) in 1995.
9. How do I know if my design is written in Verilog?
You can check if your design is written in VeriLog by looking at the top of the file. 3. What is the difference between Verilog HDL and C/C++?
A hardware description language is a programming language designed to describe the behavior of digital circuits. A hardware description language is different than a software program because it describes how the circuit works, not what the circuit should do. In contrast, a software program tells the computer what to do.
10. What is the difference among Verilog, SystemVerilog, and VHDL?
VHDL is a standard developed by the IEEE. SystemVerilog is a newer version of VHDL created by LSI Corporation. Verilog is a proprietary hardware description language created by Cadence Design Systems.
11. Is Verilog suitable for embedded systems?
Yes, Verilog is a good choice for designing embedded systems. It provides many features that make it easier to develop complex designs.
12. What is the difference in using Verilog vs. C/C++?
Using Verilog requires less time to write and debug code. However, it takes longer to compile and link. Using C/C++ requires more time to write and debug the code. But, it compiles faster and links faster.
13. Which tool do you use to generate Verilog files?
Most people use the free Cadence Code Composer Studio.
14. What does the following statement mean?
The output of a Verilog module is always 1 if its input is 0.
15. What does the following code do?
module test(input a,output b);
16. What does the following line of code mean?
always @ (posedge clk) begin
//do something else
17.What does this code do?
module top(input A, B, C);
assign D (A & B) | (~C & ~B);
18. What is the output of this code?
module top(output A, B, C, D);
input A, B, D;
assign D (A&B)|(~C&~B);
19. What is the output if we change the input of C to 0?
module top(inout A, B, C,D);
20. What does Verilog stand for?
A. Verilog stands for Very Large Instruction Set Architecture.
B. Verilog stands fro Very Long Instruction Word.
C. Verilog stands fo Very Little Instruction Word.
D. Verilog stands fop Very Little Instruction Word.
21. How many bits are in a byte?
A. 8 bits
B. 16 bits
C. 32 bits
D. 64 bits
22. What is the difference between a register and memory?
A. Registers store data temporarily while memories store data permanently.
B. Registers store data permanently while memories store data temporarily.
C. Registers store data temporally while memories store data permanently and vice versa.
23. What is RTL?
The acronym stands for Radio-Frequency Transceiver Logic. This is a type of technology that is used in electronic circuits, specifically radio frequency (RF) devices. These devices use transistors and capacitors to amplify signals and create oscillations.
24. How does RTL differ from CMOS?
CMOS stands for Complementary Metal Oxide Semiconductor. This is a type semiconductor that uses both p-type and n-type transistors. RTL uses only p-type transistors.
25. Why do we need RTL?
Because CMOS is not suitable for high power applications. RTL is much more stable than CMOS.
26. What is the difference between an IC and a chip?
An integrated circuit (IC) is a single piece of silicon that contains all the logic necessary to perform a specific function. A chip is just a small portion of an IC.
27. What is the difference betweeen a microchip and a macrochip?
A microchip is a chip that is less than 1 inch square, while a macrochip is larger than 1 inch square.
28. What is the difference btween a DIP switch and a push button?
A dip switch is a mechanical device that changes position based on how far it is depressed. A push button is a mechanical device that depresses based on how hard it is pressed.
29. What is the difference beetwen a diode and a transistor?
A diode is a two terminal device that conducts electricity in one direction. A transistor is a three terminal device that controls current flow in one direction.
30. What is the difference between a’standard’ and ‘custom’ RTL?
A standard RTL is a generic design that can be manufactured in any quantity, whereas a custom RTL is designed specifically for a particular customer’s application. A standard RTL may have some features that make it suitable for many different applications. However, if a customer specifies certain requirements, then these must be incorporated into the design before manufacturing begins.
31. How do you ensure that the product meets the customers’ expectations?
To ensure that the product meets its customers’ expectations, we conduct extensive research and testing to understand their specific requirements. We work closely with our customers throughout the design stage to identify what they need and how the finished product should behave.
32. What is the difference among a ‘product’,’service’, and ‘application’?
The three words are often used interchangeably, but each serves a slightly different purpose. A product is something tangible – a physical object, for example, a car or a pair of shoes. A service is a set of activities performed for someone else – for example, a mechanic repairing a vehicle. An application is a particular way of using something – for example, a mobile phone app that lets people book taxis.
33. What are the advantages of using a plastic mould instead of a metal mould?
Plastic molds are cheaper than metal molds and are easier and faster to produce. They are also lighter, making them easier to transport and handle. Plastic molds also tend to last longer than metal molds, since they don’t rust.
34. What does a ‘prototype’ mean?
It means a model of a device, system, or process that is built to test out ideas and functionality. Prototypes allow engineers to explore potential solutions to problems without committing time and money to production.
35. How do you know whether a product is ready for mass production?
A product is considered ready for mass production when it has been thoroughly tested and refined to be as close to perfect as possible. Products that are not yet fully developed may still be improved upon, but once they reach that point, mass production can begin.
36. What is the difference in terms of cost between developing a new product versus adapting an existing one?
Developing a new product generally involves more investment and risk than adapting an existing one. New products require the creation of a brand-new prototype, while adapting an existing product is done by modifying the original design.
37. What is the difference between a designer and an engineer?
A designer creates something that looks good, while an engineer designs something that works well. A designer is responsible for the look of a product, while an engineer is responsible for how well a product works.
38. How do you know if a product is designed correctly?
You should feel comfortable using the product. If you don’t use it often, then it’s not likely to work properly.
39. Why does a product need to have a logo?
The logo is what makes the product recognizable. Without a logo, people would never know who manufactured the product.
40. Why do some products have a tagline?
Taglines help consumers remember the brand name.
41. What is the difference in designing for print versus designing for digital?
Designing for print means making sure that the layout of text and images is appropriate for printing. Designing for digital means making sure that the website is user-friendly.
42. What is the difference when designing for mobile devices versus desktop computers?
Mobile devices are smaller than desktop computers. Therefore, designers have to make their websites small enough to fit on a smartphone screen. Desktop computer screens are much larger than smartphones. Therefore, designers have more space to create content.
43. What is the difference of designing for tablets versus laptops?
Tablets are similar to smartphones, but they’re bigger. Laptops are similar to desktops, but they’re smaller.
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