FPGA Field Programmable Gate Arrays

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Digital Design Today

Complex systems are built using:

- ASIC’s- Microcontroller

s- FPGA’s- Combination of

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System on Chip

- A typical ASIC chip today contains many subsystems, and performs very complex tasks.

- FPGA’s are also becoming big enough to contain a whole complex system.

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Micro-controller

A microcontroller is a general-purpose VLSI chip containing a small microprocessor, a small amount of memory and very limited I/O capability.

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FPGA

A Field Programmable Gate Array (FPGA) is a VLSI chip containing a large uniform array of Configurable Logic Blocks (CLB’s) that can be programmed to perform a user-defined task.

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FPGA Structure

FPGA CLB

FPGA Look up TableCombinatorial logic is stored in 16x1 SRAM Look-Up Tables (LUT’s) in a CLB.

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FPGA vs. Asics- FPGA

They are pre-manufactured. So no need to worry (much) about physical IC design.

No fabrication time. So they are faster to develop

The non-recurring engineering cost of an FPGA design is much lower than that of an ASIC.- ASICs

They are custom-designed for your system Generally lower power consumption and faster

clock rate. Require physical design and fabrication(very

expensive) Components are much cheaper in large

production runs Engineering costs are much higher

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FPGA vs. Asics vs. μP

FPGA Design Methodology

Hardware Description Language

Two major HDL’s: VHDL

standardized by IEEE in 1987,1993, 2002, 2006

object-oriented, very widely used

Verilog standardized by IEEE in 1995,

2001, 2005 has concise syntax like C

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VHDL ExampleA Multiplier Program in VHDL

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Verilog ExampleA Multiplier Program in Verilog

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Simulation

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Test & Debug

XSA-40 FPGA Development board from XESS IncShiraz University of shiraz spring 2011

Important FPGA Manufacturers

Xilinx (www.xilinx.com) Altera (www.altera.com) Actel (www.actel.com) QuickLogic (

www.quicklogic.com) Lattice Semiconductor (

www.latticesemi.com)

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FPGA Applications

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Conclusion

FPGA’s are becoming faster, denser and more capable

Using FPGA’s where it makes sense can reduce design costs and total system costs.

Use FPGA’s when: parallelism is possible speed matters Integration and reliability are

important

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QUESTIONS???

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