Automated DRC Waiver Management
This paper explains the Calibre Auto-Waiver product, and discusses how the auto-waiver process significantly reduces the time and risks associated with implementing third-party IP. Integration of third-party intellectual property (IP) into integrated circuit (IC) designs has always been a potential time trap for IC designers. IP design rule violations that were waived by the foundry show up during IC verification without any indication as to their waived status. The IC designer has no choice but to analyze and resolve these errors just like any other, wasting significant manhours and cycle time. Calibre Auto-Waiver, Calibre nmDRC's automated waiver management capability, provides IP designers with automated identification of design rule violations granted waiver status during IP development. During integration of the IP into larger designs, IC designers can use Calibre Auto-Waiver to recognize and remove these errors during design rule checking (DRC), avoiding the need to analyze and debug waived errors. In addition, Calibre Auto-Waiver identifies any waived errors that fall into "marginal" waiver status, allowing the IC designer to investigate these errors as needed to ensure manufacturability. After DRC is complete, Calibre Auto-Waiver enables the designer to quickly review the waiver status of all IP errors, as final assurance that no IP error has been overlooked.
Combining Low Pin Count Test with Scan Compression Dramatically Reduces Test Interface and Cost
The manufacturing test process for ICs is increasing in cost and effort to keep up with rigorous quality standards, complexity of newer designs and process nodes, narrower time-to-market windows, and demand to reduce test pins. DFT engineers are using advanced fault models to improve test quality. However, increasing test time and volume, which translates into increased cost, is forcing many companies to apply the necessary tests in fewer test cycles and, if possible, with fewer pins.
Low pin count testing (LPCT) is a technique to reduce the cost of test by minimizing the pin requirements of a device when tested on an ATE. By applying LPCT, devices can be easily tested on structural DFT testers at dramatically reduced costs while meeting the low pin count requirements of device and design flow. Combining LPCT with test compression further extends the test capabilities to allow application of all necessary fault models using low-cost testers that are seriously pin-limited. The techniques described here enable gains in test coverage with less application time and minimal effects on design and test overhead.