May 28, 2024
Field Programmable Gate Arrays

From Concept to Reality: Understanding Field Programmable Gate Arrays

Field Programmable Gate Array or FPGA is a type of integrated circuit that can be programmed in the field after the manufacturing process. FPGAs allow engineers to implement customized digital circuits in a flexible programmable device. Over the last few decades, FPGAs have become a popular choice for prototyping, custom hardware acceleration and low volume production of application specific integrated circuits (ASICs). Unlike application specific integrated circuits (ASICs) that are custom designed for specific applications, FPGAs can be reconfigured for different applications. This reprogrammability makes FPGAs a very flexible solution for various applications.

History and Evolution of FPGAs

The first FPGA was introduced in 1985 by Xilinx which was based on CMOS static RAM technology. This early FPGA had only 64 configurable logic blocks and limited routing resources. Over the years, FPGA technology advanced significantly with higher capacities, faster speeds and reduced power consumption. In 1990s, SRAM-based FPGAs dominated the market from Altera and Xilinx. Flash-based FPGAs were introduced in late 1990s providing non-volatile configuration but had lower densities. SRAM FPGAs continued advancing with higher logic densities, embedded memory blocks and hard processors to accelerate applications. Advanced 20nm and 16nm FinFET process nodes in recent years have enabled FPGAs with billions of transistors and complex programmable logic devices (CPLDs). Today’s high-end FPGAs can implement designs equivalent to several ASICs on a single chip.

FPGA Architecture and Configurability

The basic building blocks of an FPGA are programmable logic blocks, programmable interconnects and programmable I/O blocks. Logic blocks contain look-up tables (LUTs) and flip-flops that can be programmed to implement basic logic functions Field Programmable Gate Arrays like AND, OR, XOR etc. Interconnects allow the logic blocks and I/O blocks to be connected according to the desired design. Modern FPGAs provide thousands to millions of such configurable logic blocks, blocks of embedded memory along with digital signal processing (DSP) slices. Users implement their design by configuring these programmable elements. The configuration is stored in internal SRAM cells in SRAM-based FPGAs or flash memory in flash-based FPGAs. This configurable architecture allows implementing different circuits by programming the same FPGA chip.

Applications of FPGA

Prototyping – Engineers use FPGAs to quickly prototype digital designs before final silicon implementation. Compared to printed circuit boards, FPGA prototyping is much faster.

Hardware acceleration – Cryptographic algorithms, signal processing, computer vision and machine learning algorithms are accelerated using FPGA embedded blocks. This delivers higher performance compared to general purpose CPUs.

Embedded systems – FPGAs are preferred for low volume production of embedded systems requiring custom hardware like industrial controllers, aviation and railway equipment.

Networking equipment – Many routers, switches use FPGAs for high-speed packet processing, traffic management, encryption functions etc.

Test and measurement equipment – Industries like automotive, defense use FPGAs in oscilloscopes, spectrum analyzers for complex real-time signal processing and analysis.

Aerospace applications – Satellites use FPGAs for payload processing, fault tolerant digital processing platform. Spacecrafts use FPGAs to control systems, sensors.

In the last few decades, FPGAs have evolved tremendously with new architectures, higher capacities and faster speeds. They provide a flexible hardware platform for implementing custom circuits either permanently or reconfigurable. FPGAs have revolutionized digital design and are ubiquitous in embedded systems, consumer electronics, wired and wireless communication networks, aerospace, industrial and test & measurement equipment due to their programmability and design flexibility. With advancements in 3D stacking, non-volatile memories and other new process technologies, FPGAs will continue to play a pivotal role in digital innovation.

1. Source: Coherent Market Insights, Public sources, Desk research
2. We have leveraged AI tools to mine information and compile it