What’s In a Chip? Reverse Engineer It to Find Out
July 28, 2009--I had an interesting meeting today at DAC with Julia Elvidge, the president of Chipworks. Chipworks basically reverse engineers chips to find out exactly what makes them tick. The results may surprise you—they certainly did me.
I must admit I’ve long associated reverse engineering with shady operators who’d rather knock off your chip than invest in the R&D to develop their own. While not denying that’s been known to happen, Julia proceeded to educate me to the legitimate uses of reverse engineering.
First, reverse engineering is one way to defend your own patents. The patent jungle is so tangled, she explained, that “you almost can’t build a chip without infringing someone’s patent.” If you’re spent millions on a process that you patented—one that gives you significant product differentiation—and suddenly a competitor comes up with the same functionality, it’s time to find out whether they’re just clever or they’re stealing your stuff. Chipworks provides intellectual property services to IP groups and law firms.
How Did They Do That?
That brings us to the other reason for reverse engineering—technical competitive analysis, which Chipworks also offers. This call is often placed when the engineering manager looks at a competitor’s new product and thunders, “How the hell can their die be half the size of ours?!” You may not go down the same road they did, but the analysis can certainly make you re-examine some of your assumptions—especially when your engineering manager comes to a team meeting, plops down the reverse analysis of a competitor’s chip and says, “You told me this couldn’t be done. Here, they’ve done it. Now do it.”
Julia pointed out another scenario when competitive analysis makes sense. Say a digital design house is thinking of expanding into analog/mixed-signal products. If you haven’t done it before, it’s hard to be clear about what you’re getting into. Reverse engineering a product similar to what you have in mind will give you a good idea of what’s involved. The information may either encourage you or scare you off. Knowledge is power, even if you don’t choose to act on it. If you do, it can save your team a lot of development time—after you’ve cleared it with legal that you won’t be infringing any patents.
For design teams, in Julia’s words, “Analysis is critical to benchmarking themselves against their competitors and making better design choices.”
While I completely grok the IP/patent protection argument, I’m not as comfortable with the competitive analysis one. Chipworks is a private detective you hire to check out the competition—at least their products. Pulp fiction has given private detectives an unsavory reputation, but the service they provide is useful, legal and—when conducted appropriately—entirely ethical.
Still, if my design team had to spend 18 months coming up with a complex design, I’d rather that your design team did, too. Of course, if you’re reverse engineering our chips, I’d be a fool not to return the favor. The game just kicked up a notch.
What Can You Tell Me?
This isn’t a simple “pop the top and take a look” operation. Chipworks shaves each metal layer off a chip, stopping to polish the chip, scan it and photograph it every step of the way. Software then scans the photographs and generates either flat or fully organized electrically correct schematics. Then you can:
- Click on portions of a high-level schematic and drill down to the transistor level;
- Instantly cross-reference between the schematics and a massive image mosaic, comprised of tens of thousands of SEM images across all the layers of a device;
- Automatically define block designs and locate similar instances within the device—a feature commonly used to accelerate device analysis or find instances of patent infringement;
- Export to a variety of netlist formats for further analysis and simulation.
With all that information in hand, you at least know how much work you’ve got cut out for yourself—and a good indication of the road forward.
Like I said, the game just kicked up a notch.