Practical Chip Design

It's not often that a simple product-line extension makes it over the threshold into newsworthiness here. Generally anyone who is interested can put a ruler on the product line chart for a chip family and pretty much figure out the data sheets for any new members of the family. That could probably be said as well for Altera's Cyclone IV GX and Cyclone IV E FPGAs, which Altera announced this morning. But in a world where standard-product IC developers must look quarters ahead and try to read the odds for emerging market opportunities, a couple of chip announcements might tell us something about where the semiconductor industry is going.

The technical story on the two new product lines is pretty straightforward. Both families are build on TSMC's 60 LP process, the same low-leakage, moderate-speed process Altera used for the Cyclone III LS family in 2007. The logic array architecture is unchanged from the Cyclone III. But there are changes in two directions.

The first, predictably, is power. The IV E family is, Altera claims, the lowest-total-power member of the Cyclone family under some unstated operating conditions. Senior product marketing manager Umar Mughal said that the IV E will consume about 25 percent less power than the equivalent Cyclone III part in equivalent applications. Since the process is the same, one presumes that the improvement has been achieved through circuit-design improvements and possibly reduced operating voltage on the core. The impact on system power may be even greater, as the Cyclone IV devices require only two external power supplies, rather than the four required by Cyclone III devices. Apparently Altera has added internal regulators to make up the difference. The Cyclone IV E family spans the range from 6,000 logic elements, 300 Kbits of RAM and 15 hardware multipliers to 119,000 LEs, 3.8 Mbits of RAM and 266 multiplier blocks. The IV E chips will start at about $3 each in large quantity.

The more interesting of the two new lines is the Cyclone IV GX. These are, Mughal said, the lowest-power and lowest-cost FPGAs to include on-chip high-speed transceivers. High-speed is a relative term here, as the I/Os on the devices are rated at 3.125 Gbit/s, less than a third of the top speed of Altera's flagship Stratix IV GT parts. The reasons for this choice, Mughal said, are cost—these are new PLLs and SerDes designed from a clean sheet of paper for low cost—and the fact that most of the target applications are still using PCI Express gen 1 or Gigabit Ethernet, not the much faster connections that are going into advanced systems.

Continuing on the low-cost theme, the fast I/Os are optimized for wire-bond, not flip-chip, packaging, giving good eye openings in packages that low-cost applications can actually afford. The chips also include hard-wired PCI Express macros, so you don't use up a lot of core resources or put yourself in a timing-closure nightmare by trying to implement a PCIe MAC in the programmable logic. And there is the choice of process. Wafers at 60nm are a lot cheaper than 40nm wafers. That cross-over is still at least 18 months away, Mughal estimated. And because the GX parts are I/O ring limited by the size of the transceiver PHYs, they would gain little in area by moving to 40nm. So in this case conservative process choice is a money-saver.

Power is the other big message here. Again, the GX chips use only two supplies, and have seen incremental power improvements compared to the Cyclone III. The integrated hard MAC blocks will also substantially reduce the power required for a PCIe port. These points, coupled with their small capacity, put the Cyclone IV GX in a whole different league from the Stratix GX parts in power consumption. Altera claims that you can implement a PCIe to Gbit Ethernet bridge for under 1.5W, for example. The GX parts will range from 14K LEs, 2 transceiver pins, half a Megabit of RAM and no multipliers to 150K LEs, 8 transceivers, 6.5 Mbits of RAM and 360 multipliers. Prices will start at about $6 each in quantity.

So what does all this say about where Altera sees the market going? Power and low-cost transceivers are the big hints. Mughal said that one of the biggest growth areas Altera expects in 2010 is infrastructure upgrade in the developing world to support smart phones. "There are 2.5 billion dumb handsets in the world," he pointed out, "and many of them are in developing nations where smart phones will be coming within reach of subscribers. That's forcing carriers to upgrade their networks to handle data. But these are incredibly cost-sensitive networks." Not only are existing basestation developers working on cost reductions, but Mughal said "we are seeing tier-two developers in both Asia and Latin America jumping in with new specifically low-cost architectures for this market." The combination of low cost and low power with large multiplier complements suits the IV GX admirably for developing-world basestation designs.

In addition to the cellular infrastructure, Mughal sees opportunities opening up in a few other areas. One is in industrial networking, where the Great Recession has forced low-volume chip vendors to end-of-life a lot of specialized industrial Ethernet chips. The IV GX devices will offer the ability to drop into an existing board-level design as a bridge or substitute for an extinct ASSP with minimal changes—especially given the relaxed power supply requirements. Finally, Mughal speculates that the rumblings about 3D displays and greater-than-HD broadcast studio equipment will force systems designers in these areas to move beyond their existing discrete transceiver solutions to something faster: for example Displayport. Those new interfaces will be within the range of the GX's transceivers.

But setting aside 3D video, one suspects that Cyclone IV will be most closely watched by those companies serving the developing world wireless infrastructure market. Little deterred by the global financial crisis, that enormous mass of people using cell phones may be rapidly settling into the driver's seat of the semiconductor industry.