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The initial user programmable devices called PLDs ( programmable logic devices ) that were developed in 1978 by MMI could replace ten or so TTL gates and were one time programmable. This led to the reprogrammable PLDs based on EEPROM or EPROM technologies.
By 1985 advancing lithography enabled a new class of device, the FPGA. FPGAs introduced two important new architecture features: programmable routing to inter- connect the increasing number of gates on a device and a programmable gate called a LUT or lookup table with an associated register. The initial devices from Xilinx contained up to a hundred LUT and fl ip-fl op pairs in a basic logic element called a CLB or confi gurable logic block . Rather than using a permanently programmed EPROM or EEPROM memory, Xilinx FPGAs relied on CMOS memories to hold programming information. Figure 1.1 illustrates the technological improvement of modern FPGAs relative to the original Xilinx XC2064 which had 64 programmable logic cells.
The FPGA took its place as a central component in digital systems, replacing PLDs and TTL for implementing glue logic. In the 1990s new uses began to emerge for FPGAs, which were becoming more capable than just gluing I/O to processors. The emerging Internet became a growth driver for FPGAs with FPGAs being used for prototyping, initial deployment, and full-scale production of Internet switches and routers. By 2000 communications systems were the primary market for FPGAs. Other new markets for FPGAs also emerged for ASIC prototyping (Chap. 18 ) and high-performance DSP (digital signal processing) systems (Chap. 8 ). FPGAs also began to be used for implementing soft control processors such as the Xilinx MicroBlaze (Chap. 6 ) and PicoBlaze architectures.
Fig. 1.1 FPGA evolution since the 1980s
The original FPGA architecture was a simple implementation of a programma- ble logic block. With each new generation, new programmable functions have been added along with hardening of some specifi c functions in order to reduce the cost or improve the performance of FPGAs in digital systems. These blocks continue to evolve in each generation. Many important functions have been added since the initial FPGAs including the following:
• Fast carry chains for high-speed adders and counters
• Small memories called distributed RAM s (or LUTRAM s)
• Block memories (BRAM or block RAMs)
• A hard RISC processor block based on the PowerPC
• Multi-Gigabit or MGT serial transceivers
• The DSP48 for digital signal processing
• Hard PCI blocks
• A complete system on chip (SoC) as a hard block in the FPGA in the Zynq family of FPGAs
The inclusion of hard blocks in FPGAs is driven by the trade-off between usage and cost. For customers which use these functions, value and performance are increased; however, if these hard blocks are not used, they are wasted space which can increase cost. Additionally these hard functions require signifi cant software support to be useful to customers. For these reasons, hardening functions have been limited to those functions of clear value in important market verticals.
Manufacturer:Xilinx
Product Categories: Embedded - FPGAs (Field Programmable Gate Array)
Lifecycle:Active Active
RoHS: No RoHS
Manufacturer:Xilinx
Product Categories: FPGAs (Field Programmable Gate Array)
Lifecycle:Active Active
RoHS: No RoHS
Manufacturer:Xilinx
Product Categories: Memory - Configuration Proms for FPGA's
Lifecycle:Obsolete -
RoHS:
Manufacturer:Xilinx
Product Categories: Memory - Configuration Proms for FPGA's
Lifecycle:Any -
RoHS: -
Manufacturer:Xilinx
Product Categories: Socle de fusible
Lifecycle:Obsolete -
RoHS:
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