Kent Barclay Howieson

US Patent:

7533458, May 19, 2009

Filed:

Jul 17, 2008

Appl. No.:

12/174810

Inventors:

Moises Cases - Austin TX, US
Bradley D. Herrman - Cary NC, US
Kent B. Howieson - Austin TX, US
Erdem Matoglu - Austin TX, US
Bhyrav M. Mutnury - Austin TX, US
Pravin S. Patel - Cary NC, US
Nam H. Pham - Round Rock TX, US
Caleb J. Wesley - Winston Salem NC, US

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

H05K 3/36

US Classification:

29830, 29825, 29832, 29846, 156293

Abstract:

Methods and systems for reducing noise coupling in high-speed digital systems. Exemplary embodiments include a method, including etching a plurality of high speed signal traces onto a core insulating layer, forming trenches on respective sides of the plurality of high speed signal traces, thereby removing insulating material adjacent to the plurality of high speed signal traces and forming pedestals having remaining insulating material, the plurality of high speed signal traces disposed on and coupled to the remaining insulating material, coupling pre-preg material on the high speed signal traces, removing the pre-preg material adjacent the trenches, thereby retaining the pre-preg material aligned with the high speed signal traces, and heating and pressing a core layer to the pre-preg layer, and heating and pressing the pre-preg layer to the core insulating layer.

US Patent:

7701222, Apr 20, 2010

Filed:

Oct 19, 2007

Appl. No.:

11/875001

Inventors:

Moises Cases - Austin TX, US
Bradley Donald Herrman - Cary NC, US
Kent Barclay Howieson - Austin TX, US
Erdem Matoglu - Austin TX, US
Bhyrav Murthy Mutnury - Austin TX, US
Pravin Patel - Cary NC, US
Nam Huu Pham - Round Rock TX, US
Caleb James Wesley - Winston Salem NC, US

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

G01K 3/00
G01J 5/00
G01K 17/00
G01R 27/32

US Classification:

324501, 374122, 374137, 702136, 324637

Abstract:

A method for testing a printed circuit board to determining the dielectric loss associated with the circuit board material relative to a standard. Dielectric losses in the material generate heat when a high frequency electronic signal, such as a microwave frequency signal, is communicated through a microstrip that is embedded within the printed circuit board. The temperature or spectrum at the surface of printed circuit board is measured and compared against the temperature or spectrum of the standard to determine whether the material under test is acceptable. While various temperature measurement devices may be used, the temperature is preferably measured without contacting the surface, such as using an infrared radiation probe.

US Patent:

8084692, Dec 27, 2011

Filed:

Oct 25, 2007

Appl. No.:

11/924416

Inventors:

Moises Cases - Austin TX, US
Bradley D. Herrman - Cary NC, US
Kent B. Howieson - Austin TX, US
Erdem Matoglu - Austin TX, US
Bhyrav M. Mutnury - Austin TX, US
Pravin S. Patel - Cary NC, US
Nam H. Pham - Round Rock TX, US
Caleb J. Wesley - Winston Salem NC, US

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

H05K 1/03

US Classification:

174255, 174256

Abstract:

An apparatus having reduced noise coupling includes a core layer having an upper and lower surface, the upper and lower surface each including a copper sheet layer, a pre-preg layer having an upper surface and a lower surface, the upper surface of the pre-preg layer coupled to the lower surface of the core layer, a core insulating layer having an upper surface and a lower surface, the upper surface of the core insulating layer coupled to the lower surface of the pre-preg layer, a return current reference layer disposed on the lower surface of the core insulator layer and high-speed signal traces disposed on the upper surface of the core insulating layer, each of the high speed signal traces disposed on a pedestal defined by a section of the pre-preg layer and the core insulating layer, each pedestal being separated by an air gap disposed between adjacent pedestals.

US Patent:

7525319, Apr 28, 2009

Filed:

Aug 28, 2008

Appl. No.:

12/200208

Inventors:

Rubina Firdaus Ahmed - Cary NC, US
Moises Cases - Austin TX, US
Bradley Donald Herrman - Cary NC, US
Kent Barclay Howieson - Austin TX, US
Bhyrav Murthy Mutnury - Austin TX, US
Pravin Patel - Cary NC, US
Peter Robert Seidel - Cary NC, US

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

G01R 31/04
G01R 31/02
G01R 31/28

US Classification:

324538, 324754, 714734

Abstract:

A method of electrically qualifying high speed printed circuit board (PCB) connectors includes mounting a PCB connector on a test card, sending bit patterns through a first portion of the test card, evaluating a waveform on a sense signal on a second portion of the test card for the bit patterns launched on said first portion of the test card to measure common mode noise, and comparing the measured common mode noise of the second portion of the test card to a golden standard performed on a pre-qualified connector. The first portion of the test card comprises connectors to inject bit patterns. The second portion of the test card includes a split plane which induces common mode noise on a sense signal, the sense signal, and a termination pack. If the measured common mode noise on the PCB connector is worse than the golden standard, then the PCB connector is disqualified. If the measured common mode noise on the PCB connector is as good as or better than the golden standard, then the PCB connector is qualified.