FPGAs Gain Strength

Gaining Stronger: FPGAs with DSP will double in the next four years (left). Though they still pale compared to ASICs, sales of FPGAs are catching up (right).

Field programmable gate arrays (FPGAs) are rapidly becoming a technology for customizing even high-volume systems, erasing their reputation as an alternative for prototypes and low-volume systems. Meanwhile, prices are declining and development tools continue to evolve, prompting more engineers to use the parts to gain more flexibility, altering products even once they are available in the marketplace.

As chipmakers move to finer line-width geometries, 90 nm and below, the cost differential for FPGAs is changing. They take more gates than ASICs, but smaller geometries decrease the differential. At the same time, the cost of designing high-density ASICs is rising. "FPGAs are getting less expensive while it's costing more to do ASICs," says Tom R. Halfhill, senior analyst at In-Stat/MDR of San Jose, CA.

Engineers in many fields are switching to field programmable parts. Communication providers like the ability to change specifications even after hardware is deployed in the field (see "Good Fit For Communications on page 34). Designers of lower-volume products such as instrumentation are relying on FPGAs so their customers can work with many different types of products.

National Instruments has been using FPGAs since 1997 and plans to continue broadening its usage. "The rate we're putting LabView into FPGAs is increasing, we see it going everywhere," says Mike Santori, business and technology fellow at NI.

Some designers no longer consider ASICs, even for production runs. "FPGAs are more attractive first because our end products are usually lower volumes. ASICs are never really a consideration," says August Hidalgo, senior electrical engineer at Agilent Technologies.

ASICS still strong

But while many observers note the rapid market growth for FPGAs, ASICs aren't going to disappear any time soon. On the contrary, companies such as AMI Semiconductor of Pocatello, ID, earn significant revenue converting FPGA prototypes into ASICs for production runs.

Market watchers note that ASICs and application-specific standard parts will continue to hold sway in high volume markets. "While FPGAs will continue to erode the low-end ASIC market, they will have very little impact on the ASSP market. When it comes to volumes, ASICs will remain king," says Jerry Worchel, senior analyst at In-Stat/MDR in Scottsdale, AZ.

That erosion of low-end markets still marks a significant change. FPGAs were once used primarily for prototyping, but declining prices have prompted many to use them in production runs. ASICs still offer better pricing in high-volume applications, but the tipping point continues to change. "The point where it makes more sense to do an FPGA than an ASIC is changing yearly in favor of FPGAs, though when you're pinpointing the location of the line, the biggest of many variables is volume," Halfhill says.

Another benefit is that FPGA » hardware can be reconfigured at any time, so engineers can tweak the chips in the late stages of design, or even after the product has gone into the field. "With application-specific parts, you've got to hit the bull's-eye. FPGAs provide more flexibility," says Sandeep Vij, VP for worldwide marketing at Xilinx.

Even military designers, who are extremely concerned about reliability and the potential for malicious changes, are using more FPGAs. "The military has changed its attitude, they used to go off and design tons of ASICs" says David Squires, director of DSP marketing at Xilinx.

Some military documentation for technical specifications appear written to specify the devices, and more groups are using FPGAs, he says.

Using Reconfigurability: The changing nature of communications drives nearly half the FPGA sales this year as new standards emerge.

DSP focus

In the past year or so, DSP has become an increasing focus for FPGA providers. Altera Corp. of San Jose, CA, last month unveiled Version 2.2 of its development tools for DSP, giving designers more design capabilities for its 90-nm line, which began shipping in June of this year.

Lattice Semiconductor Corp. of Hillsboro, OR, this summer unveiled its LatticeECP-DSP line, which improves performance by 50 percent over earlier versions. That line is targeted at high-volume, cost-sensitive markets.

The Xilinx XtremeDSP makes it possible to gang together several of the multiple accumulate cores (MACs) used in DSP processors to handle complex signal processing tasks at speeds greater than those of conventional DSP devices.

"Having 512 MACs on a chip is pretty great. The most Texas Instruments has on any chip is four," says Will Strauss, president of Forward Concepts of Tempe, AZ. He notes that FPGAs with DSP capability often work to accelerate the performance of conventional DSP chips from vendors like TI.

Shrinking Size: Xilinx has trimmed the size of its DSP core while increasing speed.