The need for RPCT
A companion piece to "Reduced pin-count test," which we published in our March 2005 issue.
Jay Jahangiri, Mentor Graphics -- Test & Measurement World, 2/28/2005
Test quality is fundamental in determining the success and cost effectiveness of a product. Receiving defective parts back from customers is costly and can greatly damage a company's reputation. Testing techniques that can identify, and in some cases repair, defective parts have become an important part of a product's life cycle, mainly because the cost associated with defective parts grows exponentially as the product matures from wafer to package, board, and system.As the industry migrates to smaller geometries, the importance of high-quality testing has become apparent for improving manufacturing yields and reducing test escapes. Higher quality test comes at a cost because manufacturers must perform more vigorous testing by targeting all areas of the chip using multiple techniques. For example, at-speed testing has become critical in ensuring that devices meet timing requirements. In most cases, however, the generation of at-speed ATPG patterns results in much larger pattern sets, thus increasing test time.
Another trend that is creating new challenges is the increase in the number of package pins. Today's industrial designs may have 2000 or more pins, requiring a high-performance tester capable of supporting the large number of pins. This is due to the fact that traditional full-pin testing requires a tester to access all primary pins of a device to give the test-pattern-generation tools maximum controllability and observability.
Back to Reduced pin-count test in our March 2005 issue.
