Field Programmable Gate Array (FPGA) is an integrated circuit that can be programmed and configured by an embedded system developer once it’s been manufactured. It’s a semi-conductor device that’s not limited to any pre-defined hardware function. Rather, it’s highly flexible in its functionality and can be configured by the embedded system developer based on the design requirements.
FPGAs essentially use programmable routing channels and pre-built logic blocks to implement custom hardware functionality based on how the embedded system developers configure these devices. FPGAs are configured and programmed using hardware description languages (HDL) such as VHDL and Verilog, which are similar to those used for ASIC (application specific integrated circuit).
FPGAs offer a lot of flexibility to the embedded systems developer to program functions and features of their FPGA based product. As such, they are widely used in embedded systems and digital electronic circuits design, and generally have a well-defined place in a system’s developer’s toolbox.
Benefits of FPGA Technology
The FPGA’s global market is growing at a rapid rate, and their popularity is growing by the day. One unique feature of FPGA is that it has the best features of processor-based and ASCIs systems. Among the most compelling benefits of FPGAs are low startup cost, a very short time to market, low financial risk, and better flexibility in updating the designs, since they can be configured and programmed by the end user. Here are the main benefits of FPGAs:
Unlike microprocessors and Digital Signal Processors (DSPs), which usually execute instructions sequentially, FPGAs are able to execute instructions in parallel, and can therefore exceed the computing powers of Microprocessors and DSPs by attaining more computations per clock cycle.
With their capacity for parallel processing, FPGAs can deliver significantly more processing power per dollar in comparison to a DSP solution, especially in applications where parallelism and performance are important. Berkeley Design Technology Inc. (BDTI), the renowned benchmarking and analyst firm for embedded systems, have actually confirmed this. FPGA inputs and outputs can be controlled at the hardware level, which allows for faster response times, and specific functionality that matches application requirements precisely.
Unlike processors, FPGAs use dedicated hardware to process logic, and typically don’t have an operating system. Since they have parallel processing paths, the different instructions don’t have to contest for the same pool of processing resources. For this reason, they can reach much higher speeds, and many control loops can operate on one FPGA device comfortably at different rates.
Short Time to Market
The most important element for an embedded systems developer in the modern competitive market is to beat the challenges posed by time-to-market, when delivering the end product to the market. The developers are under constant pressure to deliver the end product into the market in the shortest amount of time possible. In such circumstances, FPGAs provide a great support and relief by substantially reducing the product development cycle, thereby delivering the end product in the shortest amount of time possible.
When compared to the ASIC design, a concept or idea can quickly be tested and verified on the hardware, without having to go through the long fabrication process of custom ASIC design. Furthermore, incremental changes in the design can be implemented and tested on the FPGA chip in a matter of hours not weeks.
With the speedy progression of FPGA technology, more advanced software is being made accessible to embedded systems developers, and these have reduced the large learning curve characterized by layers of intellection. The high-level software development tools for FPGAs usually come with valuable IP cores, with prebuilt functions to enable advanced signal processing and control, which helps the system developer to speed up the system development.
There are several layers of abstraction used in the processor based system to help schedule the different ongoing tasks, and also to share the resources among different processes. The hardware resources are typically managed by the drive layer, with the processor and memory bandwidth being controlled by the operating system. And for any given processor core, the instructions are handled sequentially. This sequential execution means that processor-based systems execute all instruction on a priority basis. As such, a high priority task might interrupt a lower priority instruction being executed currently.
Such a scenario risks the reliability of the processor based systems, especially in the time critical applications. When compared to the processor based systems, FPGAs are significantly more reliable, since the instructions are executed in parallel without the risk of time-critical high-priority instruction interrupting a critical but low priority instruction. Plus, FPGA don’t require an operating system or deterministic hardware dedicated to each task. Therefore, they are more reliable than the processor based systems particularly with the time critical applications.
The cost of a technology has a direct effect on its popularity among system developers and engineers, xilinxfpga board low cost. Custom ASIC design based solution has a nonrecurring engineering expense (NRE) that’s much higher than that of the FPGA based hardware solutions. In general, the only time ASIC design solutions cost lower is only through a bulk production, as it reduces the per unit cost substantially.
However, the ASIC designs have one major flaw: no up gradation or changes can be accomplished once the end product has been developed. Most end users want custom hardware functionality for tens to hundreds of the systems in development. And since the systems requirements do change over time, incremental changes can be implemented in FPGA based designs, at a lower cost than ASIC design based systems. The flexibility and re-configurability of FPGA based designs make them a very handy solution for most users.
Long term Maintenance
As already mentioned, FPGA chips can be reconfigured and upgraded in the field, even when the product has already been installed. Compared to the redesigning of ASIC based solutions, FPGAs are much more flexible and typically require lesser resources and time to make functional modifications and reconfigurations. Digital communication protocol is one example of a system where FPGAs can be regarded as the most desirable solution, as the parameters and specifications of protocol can change over time.
Because the FPGAs systems are reconfigurable in the field, they are flexible enough to keep up with constant up gradations and modifications that might be necessary in such a system. Moreover, more functional modifications and upgradations can be easily made to the FPGA hardware solution without a waste of time and resources in the redesign of the hardware and making modifications to the board layout.