Lsi Corporation

International Business Machines Corporation

David S Lowrie

Freeman Yingquan Zhong

Steven L Howard

Yikui (Jen) Dong

Paul Wingshing Chung

Paik Saber

Chorng K Wang

A device fabricated on a chip is disclosed. The device generally includes (A) a first pattern and a second pattern both created in an intermediate conductive layer of the chip, (B) at least one via created in an insulating layer above the intermediate conductive layer and (C) a first bump created in a top conductive layer above the insulating layer. The first pattern generally establishes a first of a plurality of plates of a first capacitor. The via may be aligned with the second pattern. The first bump may (i) be located directly above the first plate, (ii) establish a second of the plates of the first capacitor, (iii) be suitable for flip-chip bonding, (iv) connect to the second pattern through the via such that both of the plates of the first capacitor are accessible in the intermediate conductive layer. The first pattern and the second pattern may be shaped as interlocking combs.

Hybrid bump capacitor

A device fabricated on a chip is disclosed. The device generally includes (A) a first pattern and a second pattern both created in an intermediate conductive layer of the chip, (B) at least one via created in an insulating layer above the intermediate conductive layer and (C) a first bump created in a top conductive layer above the insulating layer. The first pattern generally establishes a first of a plurality of plates of a first capacitor. The via may be aligned with the second pattern. The first bump may (i) be located directly above the first plate, (ii) establish a second of the plates of the first capacitor, (iii) be suitable for flip-chip bonding and (iv) connect to the second pattern through the via such that both of the plates of the first capacitor are accessible in the intermediate conductive layer.

A digital-to-analog converter for use in a timing control loop. The converter includes a plurality of cells, each activated in response to a timing loop control signal. The converter also includes a resistive current mirror, with a first resistance R1, providing a reference curent which is mirrored in each cell by a current source FET. Each cell is constructed to switch the current from its current source FET through an output FET when a respective control bit provided to the cell is positive. Otherwise, the current is diverted through a sink FET. All of the cell output FETs are tied to a single resistance R2 which collects the currents of the active cells and provides the AC output of the converter. The converter's output is related only to the ratio R2/R1, thereby decoupling process, temperature, and voltage effects from the output of the converter.

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San Jose, CA, United States of America

David S Lowrie