International Business Machines Corporation

Campbell H Snyder

Nandor G Thoma

Joel Roger Davidson

Hehching Harry Li

Humberto Felipe Casal

Marvin L Buller

Trong Duc Nguyen

Barbara J McNelis

Yuan C Lo

A clocking system for complex electronic devices is created in an hierarchial manner whereby the master clock pulse is provided to a plurality of digital pulse aligners which in turn provide phase aligned clock signals at the field replaceable unit level to either a slave clock or a digital phase aligner. The slave clock or the digital phase aligner at the field replaceable unit level in turn provides an aligned clock pulse to a timing node on respective chips. A third level of the hierarchy provides similarly aligned pulses to individual using-circuits on the chips of the system. The digital phase aligner, aligning the output pulse at the timing node of the next level with the reference pulses being provided to the digital phase aligner at each level, insures that the timing pulses arriving at the utilizing circuits are synchronously aligned with clock pulses of the master clock. The system provides dramatic simplification of replacement of either field replaceable units or individual components within field replaceable units. The system is self-phasing and self-correcting to accommodate timing misalignments caused by any variations in the timing delays at all levels, thereby reducing the jitter that must be accommodated.

Hierarchical clocking system using adaptive feedback

Described is an improvement for thermal enhancement technology for high power dissipating plastic packaged electronic circuit chips derived from providing structural features in the plastic package adapted to snap fit with complementarily formed edges of heat sink members.

Method for attaching heat sink to plastic packaged electronic component

Growing community of inventors

Austin, TX, United States of America

Campbell H Snyder