FPGA is an abbreviation of English Field Programmable Gate Array, an on-site programmable gate array, which is a product that further develops on programmable devices such as PAL, GAL, EPLD. It is a semi-customized circuit in the field of special integrated circuit (ASIC), which has solved the deficiencies of the custom circuit, but also overcomes the shortcomings of the original number of the number of door-to-digital rectangularities.
The FPGA uses a new concept such as logic cell array, including three parts that can be configured logic module CLB (Configurable Logic Block), output input module IOB (Input Output Block, and internal connection (InterConnect). The basic features of FPGA are:
1) Using the FPGA design ASIC circuit, users do not need tickle production, they can obtain a combined chip. --2) FPGA can do other fully customized or semi-custom ASIC circuits.
3) There is a wealth of triggers and I / O pins inside the FPGA.
4) FPGA is one of the shortest design cycles in the ASIC circuit, the lowest development cost, and the smallest risk of risk.
5) FPGA uses a high-speed CHMOS process with low power consumption and can be compatible with CMOS, TTL levels.
It can be said that the FPGA chip is one of the best choices for improving system integration and reliability in small batch systems.
At present, there are many kinds of FPGAs, with XILINX XC series, TI's TPC series, Altera's Fiex series, etc.
The FPGA is a program stored in the in-chip RAM, so it is necessary to program the RAM of the slice when operating. Users can use different programming methods based on different configuration modes.
When power is powered up, the FPGA chip reads the data in the EPROM in-chips, and the FPGA enters the working state after the configuration is completed. After the power is powered off, the FPGA restores the white film, the internal logical relationship disappears, and therefore, the FPGA can be used repeatedly. FPGA programming does not have a dedicated FPGA programmer, you only need to use universal EPROM, PROM programmers. When you need to modify the FPGA function, just change the EPROM. Thus, the same piece of FPGA, different programming data, can produce different circuit functions. Therefore, the use of FPGA is very flexible.
FPGA has a variety of configuration modes: parallelism mode is a method of fpga plus EPROM; master-slave mode can support a PROM programming multiple FPGA; serial mode can be used in serial PROM programming FPGA; peripheral mode can be used as a micro The peripheral of the processor is programmed by the microprocessor.
