Verification is an important process in the development of any digital system, whether it targets an ASIC or an FPGA. The front-end design of both ASIC and FPGA is done using hardware description languages (HDL) like Verilog, SystemVerilog, or VHDL. Depending on the complexity of the design, different approaches can be used to verify the functionality of the design ranging from simple directed testing to complex constrained random and coverage driven verification.
Despite the similarities in the verification process for ASIC and FPGA, there are significant differences between the two approaches.
In this article, we will explore the differences between ASIC and FPGA verification deeply.
ASIC Verification
Application Specific Integrated Circuit (ASIC) is a chip designed for a specific application and is usually fabricated once. ASIC design is a complex process that requires a high level of experience. The ASIC verification process involves numerous stages, such as testbench development, simulation, formal verification, and emulation. The goal of ASIC verification is to ensure that the design meets the required functionality, performance, and power requirements.
One of the biggest challenges in ASIC verification is achieving high test coverage. High test coverage means that all parts of the design have been exercised and tested. This ensures that any potential bugs or issues have been identified and resolved. The most common techniques used in ASIC verification are constrained pseudo random coverage driven verification. Constrained-random testing generates random test cases that cover a wide range of scenarios and edge cases. Coverage driven verification ensures that all parts of the design have been tested.
Read more about: Chip Design Verification
The ASIC verification process is time-consuming and costly, and the risk of finding a bug after fabrication is high. If a bug is discovered after fabrication, it will cost the company hundreds of thousands of dollars, and will increase the time to market and in the worst case might lead to opportunity loss. In most cases, a chip design respin is required, which can take weeks or even months. This is why ASIC verification is a critical step in the design process. Thus, companies invest significant resources to ensure that the design is verified thoroughly before fabrication.
FPGA based Design Verification
Field-Programmable Gate Array (FPGA) is a reprogrammable chip that can be programmed and reprogrammed multiple times. The FPGA verification process is similar to ASIC verification, but there are some significant differences. Since FPGAs are reprogrammable, the risk of finding a bug after fabrication is low. If a bug is discovered during validation, it can be fixed, and the FPGA can be reprogrammed without much cost. This makes FPGA verification less critical than ASIC verification.
The FPGA verification process involves developing a test bench, running simulations, and testing on the actual system. Since FPGAs are reprogrammable, the verification process can be simplified, and complex constrained-random and coverage-driven verification flows are not always necessary. However, simplifying the verification process can lead to issues later on as debugging on a real system can be slow and hard compared to debugging using a simulator.
Functional and timing verification is required for both ASICs and FPGAs. Functional verification ensures that the design meets the required functionality, while timing verification ensures that the design meets the required timing constraints. Timing verification is critical in FPGAs since the timing constraints can vary depending on the design and the system.
Factors that Influence Verification Process
There are several factors that influence the verification process for both ASICs and FPGAs. Some of the critical factors are:
- Complexity of Design: the complexity of the design is one of the most significant factors that influence the verification process. A complex design requires more thorough verification and testing to ensure that all features of the design have been tested and that the test coverage meets the required levels.
- Time-to-Market: the time-to-market is another critical factor that influences the verification process. Companies often have tight deadlines to get their products to market, and any delays in the verification process can result in missed deadlines and lost revenue.
- Cost: the cost of verification is another critical factor that companies have to consider. ASIC verification is more expensive than FPGA verification, and companies have to balance the cost of verification with the cost of re-spinning the chip if a bug is discovered after fabrication.
Balancing Complexity, Time-to-Market and Cost
Companies have to balance several factors when selecting the verification process, such as the complexity of the design, time-to-market, and cost. Regardless of the verification process chosen, it is critical to ensure that the design is verified thoroughly to minimize the risk of bugs and issues after fabrication.
If you’re looking for reliable and efficient verification services for your ASIC or FPGA design, Aeliasoft can help. Here are some tips to help you get started:
Aeliasoft’s team of verification experts helps you choose the right verification methodology for your design and ensure that your design meets the required functionality, performance, and power requirements. With their guidance and support, you can achieve high test coverage, ensuring that all parts of your design have been thoroughly exercised and tested to identify and resolve potential bugs or issues.
