If you plan for an interview and look for mock FPGA interview questions, this article will help you with the most frequent questions. FPGA engineers and software developers are skilled experts who can overcome the interview section for getting their desired job. The critical factor is to review a list of prepared questions. The most important thing for you as an FPGA engineer is to have a deep understanding of hardware design skills. Also, testing and error handling with different electronic tools are crucial for passing the FPGA interview questions.
Having professional work experience is your competitive strength for presenting skills and your expert level at FPGA development. If you benefit from practical work experience, there is no concern for giving complete and comprehensive answers. Our advice for doing best in the interview section is to review as many questions as possible to predominate the list of essential topics and be familiar with the different forms of questions.
Steps to succeed FPGA interview questions
If you are an FPGA engineer and preparing for FPGA interview questions, we all know this is somehow tough to deal with. But, there are few steps to becoming more confident and getting deeper into the main point. But, your complicated path will be cleaned out if you read and review just some forms of FPGA interview questions.
The main point is to prepare by checking and getting familiar with the several questions that interviewers ask frequently. If you get the primary and frequent topics, then there is no concern with the interview section. However, it would be better for you to take your time providing a complete list of FPGA interview questions, which appear in the interview most times. So then, you can review different forms at any time and just by holding a digital device in your hand.
In this article, we provide the most related and worthwhile FPGA interview questions you can have in your list:
- What is an FPGA?
- What is VLSI for FPGA Manufacturing?
- Is it obligatory to buy a development board for FPGA programming?
- What are the benefits of FPGA systems and chips?
- Explain the difference between FPGA and CPLD.
- What are the frequent applications of FPGAs?
- How can we program an FPGA chip, and what are different forms of FPGA programming?
- List out leading manufacturers of FPGAs.
- What are DSMs in FPGA developing, and why do we use them?
- In FPGA systems, How can we increase clock speed?
- What is the idea of using DRC for developing FPGAs?
- Explain the main structure of FPGAs.
- What are the disadvantages of FPGAs and hardware development with them?
- What does synthesis mean?
- Can we configure CLB as RAM?
- Explain some popular debug tools for FPGA debugging.
- Why do we implement PPL in the FPGAs?
- What does block RAM in an FPGA stand for?
Above is the main list of frequently asked FPGA interview questions, and you would better overview them over and over. Then, in the next section, you can read standard answers to these questions. Note that this is crucial to stick to the main topic instantly if you await the best results attending the FPGA interview questions.
What is an FPGA?
FPGA refers to Field Programmable Gate Array, which consists of internal programmable logic blocks and interconnects. We can program logic blocks to act as logical gates, such as AND, XOR, or other entrances. More than that, logical blocks can be programmed to perform even more complex mathematical and rational functions. The application of an FPGA system depends on the user and customer’s purpose and how we program the logical blocks.
What is VLSI for FPGA manufacturing?
VLSI is a cutting-edge technology for creating integrated chips using thousands of transistors and gates. VLSI began in 1970, and it is used for creating several electronic devices like FPGAs. VLSI technology provides the ability to make very large-scale integration to achieve high-speed processing, high-performance computing, and small-size devices.
Is it obligatory to buy a development board for FPGA Programming?
FPGA chips are designed as integrated ICs that you can buy and program separately without a complete development board. But, dev boards have been designed with their attachments and have more additionals compared to FPGA chips. Thus, we can name these boards as a complete package for developing FPGAs and learning different capabilities.
What are the benefits of FPGA systems and chips?
This is one of the common FPGA interview questions that we often see in the interview section, and you can answer it as follows:
FPGAs benefit from many features and characteristics. So that you can use them as a complete controller and programmable suit for high-tech applications, the main advantages of these electronic devices are high performance, small in size, high-speed computing, programming capabilities, and the ability to use different methods for programming.
Explain the difference between FPGA and CPLD.
CPLDs usually consist of less complex logic blocks and have fewer transistors. CPLD devices are cheaper, but FPGAs are more expensive. FPGAs are being used for complex applications. In CPLD devices, you only see logical gates in which FPGAs benefit several blocks, making them suitable for embedded systems. Although FPGAs are more costly, they have more functionalities and power for performing complex tasks.
What are the frequent applications of FPGAs?
We can use these electronic devices in many cases to control different tasks and process complex functions. For example, audio processing, image processing, machine vision, robotics, communication systems, and automobile electronic systems are just a few applications of FPGA-based systems.
How can we program an FPGA chip, and what are different forms of FPGA programming?
There are many modes for programming these devices that we implement according to the situation.
- SRAM via JTAG method
- FLASH programming
- USB or SD card
List out leading manufacturers of FPGAs.
It is better to remember essential manufacturers, and this could be of the FPGA interview questions.
Several companies manufacture FPGAs that some of which are more popular among developers and supposedly reliable. Here is a list of big manufacturers that provide Field Programmable Gate Array devices:
- Xilinx
- Intel
- Altera
- Microchip
- Lattice
What are DSMs in FPGA developing, and why do we use them?
DCM refers to Digital Clock Manager, which controls the clock condition by a feedback system. This approach provides high precision output, and it is more stable to temperature and voltage change than regular clock generators.
In FPGA systems, How can we increase clock speed?
We can change clock frequency by changing crystal type or by reconfiguring the DCM. But there is a must to check maximum clock support of the chip before the reconfiguration.
What is the idea behind using DRC for developing FPGAs?
DRC, the short form of Design Rule Checking, is to run a command to ensure there will not be any problem with the current design. Manufacturers have set the rules in the characteristics of FPGAs, and DRC is to check the constraints of technology for any parameter failures or design limits.
Explain the main structure of FPGAs
Asking about the structure of FPGAs is common in FPGA interview questions.
FPGAs consist of three main blocks:
- Configurable logic blocks
- Programmable interconnects
- Programmable input/output ports
What are the disadvantages of FPGAs and hardware development with them?
The critical disadvantage of these devices is that they are costly compared to other embedded systems’ components. Also, FPGAs have limits in production quantity, and you need to learn a different language for programming them. Another problem compared to ASICs is that there is not a thorough approach to control power consumption.
What does synthesis mean?
As you understand from its naming, synthesis is the process of converting written codes into logical gates. The program is written in the HDL language. In the next step, the synthesis process should produce a netlist for implementing gates as programmed.
Can we configure CLB as RAM?
Yes. Each CLB consists of combinational logic, registers, and other parts. They are configurable logic blocks for programming as RAM.
Explain some popular debug tools for FPGA debugging.
All FPGA manufacturers also have their exclusive debug tools. There are main debugging tools as follows:
- Xilinx chip scope
- Synopsys protolink
- Altera on-chip debugging
Why do we implement PPL in the FPGAs?
The Phase Locked-Loop system is a closed-loop frequency controller that compares the phase difference between input and output signals. The PLL controllers are the pivotal parts of the DSP systems. They are being used to generate definite and desired signals matched with the input signal phase.
What does block RAM in an FPGA stand for?
Block RAM stands for Block Random Access Memory, which provides an extensive data storage structure on a chip. We can use Block RAMs to achieve these goals:
- Storing large amounts of data more efficiently
- Transferring data between two clock domains using local FIFOs
- Transferring data between FPGAs using P2P FIFOs
- Implementing DMA FIFO for sharing data between FPGA and a host processor
Conclusion
FPGA interview questions are all about your work experience and knowledge about various peripheral devices. Also, suppose you are an expert at VHDL programming and testing. In that case, you only need to review different question forms for overcoming the challenging interview section. There is a need to answer short and without unnecessary explanations. All you need is to check the list of FPGA interview questions continually and present your skills thoroughly.
Frequently Asked Questions
How many are FPGA interview questions expected to be in the interview section?
- This depends on the interviewer and the company’s policy. But, there is an expectation of having 10 to 30 questions in the interview section.
How much time will it take in the interview section to get the FPGA engineer job?
- It will be between 30 minutes to one hour. But according to the number of questions, it may be more than one hour.
What are the most important topics that are asked in the FPGA interview questions?
- The critical questions are mainly about general topics, VHDL language, hardware, testing, and debugging.
Will we get the FPGA engineering job without passing the interview section?
- The interview section is an inseparable part of getting a job after applying for it. So you should attend and get it done with your work experience and knowledge.
What is the most notable thing to pass the interview section without any difficulty?
- It would be better for you to use your previous knowledge and work experience and give short, comprehensive, and convincing answers to FPGA interview questions.
