FPGAs stand for field-programmable gate arrays. FPGAs are semiconductor devices designed to be reconfigured to the desired application after manufacturing. Essentially FPGAs are an integrated circuit (IC) that a user can program to carry out one or more logical operations. Field programmable refers to the reconfiguration of these devices after manufacturing, whereas arrays refer to the Integrated circuits. Unlike processors, FPGAs are parallel in their work. The performance of any application is not affected when more tasks need processing because each task is assigned and processed using a dedicated section of the FPGAs
FPGAs structure varies from manufacturer to manufacturer, but a generic FPGA contains the following features: Programmable logic blocks (PLBs), Programmable I/O blocks, and Programmable Interconnect resources (PIRs).PLBs implement a logic function with various logic components such as transistor pairs, Carry and control logic, and look-up tables (LTUs). Logic blocks consist of thousands to millions of transistors. Programmable I/O blocks are responsible for connecting external components with logic blocks via interfacing pins. PIRs provide a routing path for PLBs. They are electrically programmable connections that are pre-laid either vertically or horizontally. Routing paths contain wire segments of different lengths. The density of FPGAs depends on the number of segments in the routing path.
FPGAs are classified into three categories based on the internal arrangement of blocks Symmetrical arrays, Row-based architecture, and Hierarchical PLDs. Symmetrical arrays consist of horizontal and vertical PIRs that interconnect a two-dimensional array of logic modules. Row-based architecture alternates rows of logic blocks with PIRs. The input/output block is located at the periphery of the rows. Hierarchical PLDs consist of a logic block and interconnectors at the top level. There are several logic modules in each logic block.Similarly, based on programming, FPGAs are classified into three types: Flash-based FPGAs, Antifuse-based FPGAs, and SRAM-based FPGAs.
FPGAs are expensive due to the amount of silicon required in their manufacturing and the amount of research and development it takes to design a chip and the tools that come with it. The number of transistors in FPGAs determines the amount of power it needs to operate. So why use FPGAs at all? There are two things to consider when it comes to the advantages of FPGAs. FPGAs provide you with the opportunity to choose between programming a custom digital circuit with your discrete logic or creating the circuit directly in silicon. Each of these options has its respective advantages/disadvantages. FPGAs can perform multiple independent tasks simultaneously by designating dedicated portions of the FPGAs to perform individual tasks. This process increases the performance of FPGAs exponentially. So, in fields where high performance and large computation are required, FPGAs are the ideal candidates.
FPGAs are used in many industries and applications such as the Energy sector (renewable energy, automotive industry, aerospace, and defense sector, Analog to digital converters, artificial intelligence, ASIC Prototyping, Broadcast & Pro AV, Video & Image Processing, Wired and Wireless communications, medical industry, consumer electronics and high-performance computing and data storage.