Field-Programmable Gate Arrays (FPGA) are a powerful new breed of chips that are designed to run on programmable logic rather than application specific integrated circuit (ASIC) technology. While the majority of FPGAs available now have traditionally been used in the aerospace and automotive industries, they are quickly becoming a common sight in almost every aspect of modern life.
FPGAs enable chipmakers to build software into hardware, making it possible to design devices with greater flexibility and responsiveness. This article explains what an FPGA is, how it works, and why it’s become such a hot topic in the electronics industry and beyond.
What is an FPGA?
An FPGA (field-programmable gate array) is a type of digital device that can be programmed to perform a wide range of functions, depending on the design of the device. Most commonly, it is used as a circuit design tool where the functionality is “programmable” (i.e. the functionality can be changed) by implanting a custom design into the chip.
FPGAs offer a number of advantages over traditional analog and/or digital designs, including reduced manufacturing costs, increased flexibility in design, simplified development processes, and ease of programming.
How Does an FPGA Work?
An FPGA device consists of a number of interconnected circuit blocks (input/output buffers, flip-flops, etc.) that are each programmed as a single unit. These blocks are logically connected together via programmable interconnections, allowing you to create complex logic circuits. The programmable blocks are essentially logic gates, which means they can be programmed to perform a wide range of logical functions.
Additionally, each block is linked to other blocks via logic gates called flip-flops, which, if triggered at the same time, generate a unique output. When designing an application with an FPGA, you can specify the functionality and pin assignment requirements in the “ design rules ”.
These rules determine what type of logic design is possible, as well as which circuit blocks can be used. When logic is designed into an FPGA, it is designed as a “ bare ” circuit. That is, the circuit blocks are not connected in any specific way, and the connections are left open (i.e. “ free-form ”). This allows the designer to design the logic to any desired functionality.
Advantages of Using an FPGA
Advantages of using an FPGA in your designs include the following: Increased flexibility – With an FPGA, you can design a more flexible and dynamic circuit. In some applications, this may be desirable, since it means you can design a device that reacts to external stimuli differently from what was originally intended.
Reduced development and manufacturing costs – With an FPGA, you only buy the chips you need to build the unit. This may result in a 5 to 10 times savings over the price of a standard IC. Increased speed – In a typical 100-QFN package, an FPGA can fit into the space once occupied by a few hundred logic elements. This may result in a 5 to 10 times reduction in development time.
Disadvantages of Using an FPGA
FPGAs have a number of advantages and disadvantages, including the following:
Increased flexibility – With an FPGA, you can design a more flexible and dynamic circuit. In some applications, this may be desirable, since it means you can design a device that reacts to external stimuli differently from what was originally intended.
Increased software complexity – To get the most out of an FPGA, you need to be familiar with the toolchain and development processes used in the computer industry. This is often not the case for manufacturers who have relied on integrated circuit technology for years.
Increased cost – It costs more to design with an FPGA. This is due to the additional complexity of the design rules and the additional design time required for the board design.
Increased power consumption – While RFID tags and sensors powered by energy-sucking RFID transmitters only consume a small amount of power, FPGAs consume significant amounts of power. This is due to the fact that they are operating at full speed, generating large amounts of electricity.
Summary
An FPGA is a digital device that can be programmed to perform a wide range of functions, depending on the design of the device. Most commonly, it is used as a circuit design tool where the functionality is “programmable” (i.e. the functionality can be changed) by implanting a custom design into the chip.