SynTest Receives A Patent for Eliminating Unpredictability of ATPG Capture results due to Unknown ('X') Values when Using Test Compression

"Mask Network Design for Scan-based Integrated Circuits"

SAN JOSE, Calif., April 25, 2006 -- SynTest Technologies, Inc., a leading supplier of Design-for-Test (DFT) tools, was granted 76 claims on April 18, 2006 under United States patent number 7,032,148 for its invention of selectively masking off unknown ('X') captured scan data in first selected scan cells from propagating through the scan chains.

The patented invention are methods and apparatus for selectively masking off unknown ('X') captured scan data in scan cells from propagating through the scan chains for test, debug, diagnosis, and yield improvement of a scan-based integrated circuit in scan-test mode or self-test mode. The method and apparatus further includes an output-mask controller and an output-mask network embedded on the scan data input path of scan cells, or a set/reset controller controlling set/reset inputs of selected scan cells. A synthesis method is also proposed for synthesizing the output-mask controller and the set/reset controller. The patented inventions are used in SynTest products VirtualScan for ATPG pattern compression and TurboBIST-Logic for self-test, in use worldwide today, resulting in improved yield, productivity and time-to-market (TTM). The patented inventions also aid in improved debug and diagnosis of integrated circuit.

About SynTest

SynTest Technologies, Inc., established in 1990, develops IP for advanced design-for-test (DFT) and design-for-debug/diagnosis (DFD) applications and markets them throughout the world, to semiconductor companies, system houses and design service providers. The company has filed more than 20 US/PCT patents of which 3 have been issued and 2 allowed. The Company¡¯s products improve an electronic design¡¯s quality and reduce overall design and test costs. Various applications that use these IP (intellectual properties) include logic BIST, memory BIST, boundary-scan synthesis, Scan/ATPG with test compression, concurrent fault simulation, silicon debug and diagnosis. The company headquartered in Sunnyvale, California, has offices in Taiwan, Japan, Korea and China, and distributors in Europe and Asia including Israel. More information is available at

SynTest Technologies Inc. is headquartered at 505 South Pastoria Ave., Suite 101, Sunnyvale, California 94086, Phone: 408-720-9956, E-Mail:

SynTest and TurboBIST-Logic are trademarks of SynTest Technologies, Inc. All other trademarks are property of their respective owners.

ATPG: Automatic Test Program Generation
BIST: Built-In Self-Test
DFT: Design-for-Test
DFD: Design-for-Debug/Diagnosis
IP: Intellectual Property
TTM: Time-to-Market

For more information:
SynTest contact info: Ravi Apte
Tel:1- 408-720-9956 ext. 300