International Business Machines Corporation

Cadence Design Systems, Inc.

Louis Christopher Milano

Vivek Chickermane

Krishna Chakravadhanula

Brian Edward Foutz

Paul Alexander Cunningham

Michael Patrick Vachon

Steev Wilcox

Dale Meehl

David George Scott

Eric Eugene Retter

Roger Sherman Rutter

Systems and methods efficiently bring additional variables into a Pseudo-Random Pattern Generator ('PRPG') in the early cycles of an automatic test pattern generation ('ATPG') process without utilizing any additional hardware or control pins. Overscanning (e.g., scanning longer than the length of the longest channel) for some additional cycles brings in enough variables into the PRPG. Data corresponding to earlier cycles of the ATPG process is removed.

Method and system for improving efficiency of sequential test compression using overscan

Systems and methods disclosed herein provide for utilizing extra variables in the decompression equation set of an ATPG process for test patterns requiring an excess number of care bits than can be supported efficiently by the current hardware. An elastic interface is utilized between a tester and a decompressor network (e.g., sequential and combinational decompressors) in order to expand the test pattern length and/or the number of input variables. The systems and methods also provide care bits in early scan cycles of the ATPG process for sequential decompressors starting from a fixed state.

Elastic compression-optimizing tester bandwidth with compressed test stimuli using overscan and variable serialization

An apparatus and method for synchronizing multiple circuits or chips clocked at a divided phase lock loop (PLL) frequency. The apparatus generally includes a plurality of chips, each chip including a phase locked loop (PLL) and a circuit for generating a system clock signal, a circuit for receiving the lock signal from each PLL and for generating an All-Locked signal in response to all of the PLLs achieving lock, and a synchronizing circuit for synchronizing the system clocks of the plurality of chips upon receipt of the All-Locked signal.

Apparatus and method for synchronizing multiple circuits clocked at a divided phase locked loop frequency

Disclosed is an integrated microprocessor chip. The chip includes a digital video decoder Inverse Discrete Cosine Transform element and an on chip Read Only Memory. The on chip Read Only Memory includes (a) a shift register latch for receiving data from off chip pull-up resistors, (b) a register for storing data, (c) a selector and a decoder for selecting memory cells to be read from the register, and (d) a Read Only Memory data output.

Integrated circuit including fully testable small scale read only memory

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Endwell, NY, United States of America

Louis Christopher Milano