Field-programmable gate array (FPGA)
A Field-Programmable Gate Array (FPGA) is a type of integrated circuit that can be reprogrammed after manufacturing, offering unique versatility compared to traditional chips. These chips are constructed from silicon and integrate numerous tiny components, such as transistors, resistors, diodes, and capacitors, that enable them to perform complex calculations and process data. FPGAs can be tailored to specific applications using a specialized programming language known as hardware description language (HDL), allowing engineers to adjust their functionality over time as project needs evolve.
Unlike standard chips, which come with fixed programming, FPGAs provide the flexibility to adapt to various functions, making them particularly valuable in fields like telecommunications, data processing, and high-end electronics such as medical devices and televisions. They serve critical roles in managing and processing data within computer systems, often functioning as the core processing unit. While they are not typically used in personal computers, their ability to be reprogrammed repeatedly sets them apart from other types of memory, such as read-only memory (ROM) or programmable read-only memory (PROM). Overall, FPGAs represent a significant advancement in integrated circuit technology, enabling innovative applications across diverse sectors.
On this Page
Subject Terms
Field-programmable gate array (FPGA)
Field-programmable gate arrays (FPGAs) are specialized integrated circuits. Integrated circuits are computer chips composed of a layer of silicone, metal, transistors, diodes, capacitors, and resistors. They are used in most modern electronic devices.
Integrated circuits are capable of processing data. As integrated circuits grow more powerful, they are able to perform more calculations at a more rapid pace. Performing more calculations allows a computer to execute complex tasks with greater speed.
Most chips leave the factory with set programming. FPGA chips can be reprogrammed by computer engineers and programmers. This makes them significantly more versatile than other forms of computer chips and allows computer engineers to tailor their hardware to their specific needs. Some FPGA chips, such as erasable programmable read-only memory (EPROM) chips, must be removed from the computer and undergo a special process in order to wipe their memory clean. Other chips, such as electrically erasable programmable read-only memory (EEPROM), can be wiped and reprogrammed without being removed from the computer itself.
Background
A field-programmable gate array (FPGA) is a type of integrated circuit that can be reprogrammed after it is manufactured. An integrated circuit is a small computer chip, usually made of silicon. These chips hold a large number of tiny structures called transistors, resistors, diodes, and capacitors. This allows the integrated circuit to perform calculations and store data.
Transistors function as switches. They can turn on the supply of electricity to the circuit, turn it off, or amplify it. When used as switches, large numbers of transistors can be used to store information.
Resistors limit the amount of electricity passing through an integrated circuit, allowing the circuit to control exactly how much electricity passes through it. The ability to control how much electricity passes through the integrated circuit allows resistors to control functions such as the volume of a speaker.
Diodes are used to stop electricity from passing through an integrated circuit when certain conditions are met. Capacitors are used to store energy from an external source, such as a battery or power cable, and then release it in a short period of time.
Integrated circuits are manufactured in both digital and analog form. Analog devices, including analog integrated circuits, use some form of physical notation to read and write data. For example, an analog record player reads the physical grooves on a record to produce music. Digital devices use digital representations of ones and zeroes to approximate data. While less accurate than analog data, digital data is much easier for devices to read and write. This allows for faster reading and writing, which in turn allows for faster calculations.
Both digital and analog integrated circuits function using logic gates. Logic gates perform basic logical functions, which can then be used in computations. They switch between a one and a zero based upon predetermined conditions. In some circuits, these conditions cannot be changed once they are set. In integrated circuits, the conditions surrounding logic gates can be reprogrammed. Some devices have just a few logic gates. Others, such as complicated microprocessors, may have millions of logic gates for performing computations.
Overview
Because of their versatility, integrated circuits can be used for a number of purposes. They can be built as computer memory, timers, oscillators, amplifiers, and any number of other objects. In computers, integrated circuits often serve as the central processing unit (CPU) of the machine. The CPU is tasked with receiving all information input into the computer, sorting it, and sending the information wherever it needs to go. For example, signals sent by the mouse and keyboard are routed to the CPU, which then sends information about mouse movements and keys pressed to other parts of the computer. Some CPUs utilize multiple integrated circuits as cores, allowing an increased number of calculations to be made at one time. Increasing the number of calculations that can be made at one time increases the processing power of the machine, allowing it to perform more complex tasks.
Most integrated circuits are built as read-only memory (ROM) chips or programmable read-only memory (PROM) chips. ROM chips function in a set way after leaving the factory. Their programming cannot be altered. PROM chips can be altered a single time, and then never again. This protects chips from interference and ensures that they will always perform their intended purpose.
FPGA chips can be reprogrammed using a specific language known as hardware description language (HDL). This allows FPGA chips to be adapted to numerous purposes throughout their lifetimes. Commercial computer engineers utilizing FPGAs could periodically alter the chip's programming to ensure that it is best serving whatever purpose they intend for their equipment. FPGAs are not intended for personal computers but are used in the telecommunications industry, data processing centers, and commercial grade computers. They may also be used in high-end electronic devices, such as televisions and medical equipment.
Over time, PROM chips evolved into two types of integrated circuits: erasable programmable read-only memory (EPROM) and electrically erasable programmable read-only memory (EEPROM). EPROM chips are reprogrammed through erasing the current memory of the chip. This is accomplished through shining a powerful ultraviolet light through a specialized window on the chip itself. Because intense sunlight is sometimes powerful enough to cause damage to a chip's memory, the specialized window is normally covered while the chip is in use.
EEPROM chips can be erased by higher than normal levels of voltage passing through the chip. Because the level of electricity passing through the chip is regulated, the memory on the chip can be erased using power from the computer itself. This means that the chip does not need to be removed from the computer to be erased or written to, making it extremely useful. However, as a consequence of this process, EEPROM chips have a set number of times they can be erased before ceasing to function.
Bibliography
Awati, Rahul. "EEPROM (Electrically Erasable Programmable Read-Only Memory)," TechTarget, May 2022, whatis.techtarget.com/definition/EEPROM-electrically-erasable-programmable-read-only-memory. Accessed 7 Nov. 2024.
Brush, Kate. "Programmable Read-Only Memory (PROM)," TechTarget, Aug. 2019, whatis.techtarget.com/definition/programmable-read-only-memory-PROM. Accessed 7 Nov. 2024.
"FPGA." TechTerms, 4 Sept. 2015, techterms.com/definition/fpga. Accessed 7 Nov. 2024.
"Integrated Circuit." TechTerms, techterms.com/definition/integratedcircuit. Accessed 7 Nov. 2024.
"Processor." TechTerms, 9 Apr. 2012, techterms.com/definition/processor. Accessed 7 Nov. 2024.
Stone, Dan. "Where Is the ROM Chip Located in a Computer?" TechWalla, www.techwalla.com/articles/where-is-the-rom-chip-located-in-a-computer. Accessed 7 Nov. 2024.