International Business Machines Corporation

Mark E Turner

Douglas Willard Stout

Charles Luther Johnson

Robert Russell Williams

Pamela Sue Gillis

Dennis T Cox

Bruce George Rudolph

Robert W Bassett

David LeRoy Guertin

Jeannie T Panner

A method and apparatus for designing very large scale integrated circuit devices, most particularly level sensitive scan design (LSSD) devices, by inclusion of a plurality of distributed delay lines originating at input terminals of the device, and controlling the inhibiting and enabling of driver circuits connected to the output terminals of the device, as required to regulate operation of device drivers during a plurality of testing operations.

Integrated circuit driver inhibit control test method

A performance-sensing element (PSE) circuit detects the actual speed of other circuits on the same chip by launching a pulse into a tapped cascade of circuits on the chip, then detecting how far the pulse has progressed after a known interval. Control signals indicating circuit speed can stabilize parameters of the other circuits, such as rate of change of current (di/dt) in driver circuits, absolute delay of clock signals from one chip to another, and relative delay of multiple clock signals within the chip.

VLSI performance compensation for off-chip drivers and clock generation

Growing community of inventors

Colchester, VT, United States of America

Mark E Turner