Antipiracy solutions have become increasingly critical in the IC industry. The U.S. Department of Commerce estimates that in 2006, intellectual-property theft cost U.S. companies nearly $250 billion in lost sales and contributed to the loss of 750,000 jobs.
Historically, however, antipiracy solu- tions have been expensive and difficult to implement. Separate solutions can be priced at more than $100,000, not counting the royalty fee. Implementing them may also increase design size.
One emerging solution is to use nonvolatile, one-time-programmable (OTP) memory to implement antipiracy solutions on ICs. This effective, simple and low-cost approach uses a random number generator to create a unique identification number from a large pool.
For example, consider a 10-digit serial number, providing 10 billion possible combinations. During configuration, the identification number would be stored in the on-chip OTP memory. Each memory block would be given a different number that would then serve as a unique designation for the IC. This number would be stored in a highly secure database of valid identification numbers that only key parties could access. If, say, 10 million numbers were assigned to a specific lot of ICs, it would be prohibitively work-intensive for pirates to guess the valid identification number successfully.
As with any antipiracy solution, there would still be a small probability (1/1000) that a pirate could guess the valid identification number. If a manufacturer found that error rate unacceptable, then a larger number pool could be created.
If a device came under suspicion as a possibly pirated unit, the unique identification number could be retrieved. The identification number would then be checked against the database of valid serial numbers. If the numbers did not match, piracy would be confirmed.
Another OTP antipiracy scheme provides additional design security, ensuring that only select individuals will be able to retrieve the identification number. A developer who wants to retrieve the identification number from the IC enters a predetermined code. If the correct code is not provided, the identification number cannot be accessed.
OTP memory technology
Antifuse memories that are easily implemented in standard logic CMOS and require no additional or postprocessing steps are a good fit for antipiracy applications. To maximize reliability, the memory should generate and confine the voltage entirely within the memory cell, guaranteeing that only the programmed cells see the high voltage. Thus, the reliability of unprogrammed cells or other devices on an IC will not be affected. Memory produced in this technology also avoids the data retention issues associated with floating-gate designs. IC makers looking to implement antipiracy protection should consider OTP memory.
Charles Buenzli is vice president and chief operating officer of Novocell Semiconductor Inc. (Hermitage, Pa.) He holds a bachelor's degree in electrical engineering from the Massachusetts Institute of Technology.<