XCS40-4BG256C

Embedded - FPGAs (Field Programmable Gate Array)

Field Programmable Gate Array (FPGA)s are specialized integrated circuits (ICs) that are programmable in the field-- after manufacture. This is in contrast to Application Specific Integrated Circuits (ASICs), where the ICs are custom fabricated to a customer\'s needs. The XC40-4BG256C FPGA is one model of this type of device, with a range of uses, configurations, and capabilities.

XC40-4BG256C Applications

The XC40-4BG256C is the fourth generation in the Xilinx XC4000 family of FPGA devices. It is fitted with a low power 650MHz ARM905 processor, 16Mb SRAM memory, and 2k of block RAM, a digital signal processing display unit, and various inputs and outputs (I/O). The device is designed for power and data intensive applications, and can be used in low-cost embedded systems, digital signal processing, automotive modules, and home entertainment systems.

Because of its low power consumption and small physical size, the XC40-4BG256C is well-suited for applications that demand efficient power consumption in a small package. This might include, for example, low power video downscaling in low cost cameras; home energy monitoring; motor control applications; and satellite communications.

Working Principle

FPGAs are a type of semiconductor device that can be configured or programmed to function as any type of logic circuit. The XC40-4BG256C contains millions of logic cells connected together. Each logic cell is composed of a number of flip-flops and programmable logic gates. By way of its programming, these logic cells can be connected together to form a vast variety of arrangements and create digital circuits.

To program the FPGA, a customer creates a file, knows as a design file, which describes the exact logic circuit they want to build—this is known as the ‘netlist’. This design file is fed into a programmable logic controller (PLC) which converts the netlist into binary code. This code is then transferred to the FPGA where it configures the logic cells to produce the desired logic circuit. The FPGA can then be used to execute the logic circuit.

At first, this might sound like a lengthy and involved process. However, the advantages of using FPGAs far outweigh the time spent in configuring them—with the throughput of electronic circuits that can be designed for the cost and power of the device being no small benefit.

Conclusion

The XC40-4BG256C field programmable gate array (FPGA) is a versatile device that can be used in a variety of applications from low-cost embedded systems to motor control applications. The secret to its versatility lies in its programmability in the field—with the logic cells being programmed with a customer’s specific requirements in mind. This ease of use and low power consumption make it an ideal choice for use in a variety of projects.