Hewlett-packard Development Company, L.p.

Hewlett Packard Enterprise Development LP

Hewlett-packard Company

Colorado State University Research Foundation

Karl Joseph Bois

David W Quint

Mark D Frank

Jerimy Nelson

Elene Chobanyan

Benjamin Toby

David P Kopp

Melvin K Benedict

David Marshall

Timothy L Michalka

Michael J Tsuk

Yong Wang

Randy K Rannow

Vaishnav Srinivas

James David Stewart

Brian Kirk

Derek L Knee

Arlen Lee Roesner

Dacheng Zhou

Robert J Brooks

Steven Martin

Reza Zoughi

Elias Gedamu

Peter Shaw Moldauer

Robert J Blakely

Dave Mayer

Kimberly E Kurtis

Shad R Shepston

Charles Andrew Hartman

Aaron D Benally

Christian Olsen

Ramon R Campa

One aspect provides a printed circuit board (PCB). The PCB includes a transmission line to transmit signals of a desired frequency, a first stub coupled to the transmission line at a first location, and a second stub coupled to the transmission line at a second location. The first stub is to filter out signals of a first frequency, the second stub is to filter out signals of a second frequency, and the first and second stubs are positioned such that an insertion loss of the transmitted signals of the desired frequency is substantially minimized.

Double stub transmission line for suppression of harmonics

A signal cable for an AC-coupled link, may include: a signal conductor; a dielectric surrounding the signal conductor; and a ground sheath having a conductive layer disposed at least partially around the conductor such that the dielectric is positioned between the ground sheath and the signal conductor, wherein the conductive layer comprises a first portion extending in a first direction along the cable and a second portion extending in a second direction, opposite the first direction, along the cable and further wherein the first and second portions of the conductive layer are separated from each other by a gap, the gap being dimensioned to provide a determined amount of capacitance in series in the ground sheath. The gap may form a complete separation between the first and second portions of the conductive layer.

AC-coupling structure in electrical cabled interconnect

Systems and assemblies are provided for transposition channel routing where the characteristics of an escape route can be modified on a printed circuit board (PCB) in a manner that reduces crosstalk and realizes significant signal quality improvement. The techniques involve 'transposition' of a signal line pair on the PCB, reduces effect coupling coefficients for individual aggressor signals, thereby reducing the crosstalk. Transposition channel routing techniques can also be applied to other areas on a PCB (e.g., other than escape routes) where space is constrained and other mitigation techniques are not possible. The PCB can include an array of contact pads, a plurality of signal line pairs that include an escape route. One or more transposition junctions disposed within the escape route can route a signal line pair from a first routing channel in the escape route into a second routing channel in the escape route.

Methods and systems for transposition channel routing

A multiple-layer circuit board has a signaling layer plane, an exterior layer plane, and a ground layer plane. A pair of differential signal lines implemented as strip-lines are within the signaling layer, and propagate electromagnetic interference (EMI) along the signaling layer. A dual slot common mode noise filter may be etched within the ground layer and may include a first U-shaped etching pair comprising a first U-shaped etching and a second U-shaped etching opposing the first U-shaped etching within the ground layer plane.

Dual slot common mode noise filter

Systems and assemblies are provided for exchanged signal routing where the characteristics of an escape route can be modified on a printed circuit board (PCB) in a manner that reduces crosstalk and realizes significant signal quality improvement. Exchanged signal routing techniques involve 'exchanging' the signal routing lanes on the PCB, which reduces coupled signal amplitude and phase relationship. Exchanged signal routing techniques can also be applied to other areas on a PCB (e.g., other than escape routes) where space is constrained and other mitigation techniques are not possible. A printed circuit board (PCB) can include an array of contact pads, a plurality of signal lines that include an escape route. One or more exchange junctions disposed within the escape route can route a first signal line of a first routing channel in the escape route into a second routing channel in the escape route.

Methods and systems for exchange bus routing

A printed circuit board (PCB) may include a signal layer having a functional region and a PCB signal layer testing region. The PCB signal layer testing region may include a first differential pair having a first length formed on the signal layer, a second differential pair having a second length, different than the first length, formed on the signal layer and a third differential pair having a third length, different than the first length and different than the second length, formed on the signal layer.

Printed circuit board signal layer testing

A system may include an input engine and a void avoidance engine. The input engine may access an electronic circuit design of an electronic design automation (EDA) tool as well as identify a first net and a second net in the electronic circuit design. The void avoidance engine may perform a void avoidance verification scan to determine whether the first net, the second net, or both, are within a threshold distance from any voids in the electronic circuit design. The void avoidance engine may also generate a double violation alert responsive to a determination that the first net and the second net are both within the threshold distance from a particular void in the electronic circuit design and that the first net and the second net are located on different sides of the same plane of the electronic circuit design.

Void avoidance verifications for electronic circuit designs

An example system includes a communication channel and at least one tuning structure coupled to the communication channel. The tuning structure includes a branch of the communication channel. The tuning structure is to dissipate energy from the communication channel at least at one selected wavelength. The branch of the communication channel is a terminated portion.

Communication channel with tuning structure

A multiple-layer circuit board has a signaling layer, an exterior layer, and a ground layer. A pair of differential signal lines implemented as strip lines are within the signaling layer, and propagate electromagnetic interference (EMI) along the signaling layer. An element conductively extends inwards from the exterior layer. A void of a defected ground structure within the ground layer has a size, shape, and a location in relation to the element to suppress the EMI propagated by the strip lines. A resistive material of the defected ground structure along a perimeter of the void improves suppression of the EMI propagated by the strip lines, via the resistive material absorbing the EMI.

Defected ground structure with void having resistive material along perimeter to improve EMI suppression

An example communications device may include a slicer that may generate a digital output signal by thresholding a received signal according to variably set timing and voltage parameters. Testing circuitry may determine expected bit error ratios for multiple time-voltage slicer by performing test operations corresponding respectively to the multiple time-voltage slices. Each of the test operations may include setting the timing and voltage parameters of the slicer based on the corresponding time-voltage slice, periodically measuring a number of total bits and a number of erroneous bits based on the digital output signal and calculating a two-sided bit error ratio frequentist confidence interval (FCI) size from the measured bit error ratio. The measured bit error ratio is output in response to the two-sided bit error ratio FCI being less than or equal to a two-sided bit error ratio interval target size.

Bit error ratio tests with two-sided bit error ratio frequentist intervals

An electronic device includes a printed circuit board. The printed circuit board includes a plurality of different signaling planes and a plurality of different reference planes. A single ended via interconnects the plurality of different signaling planes. A return via interconnects the plurality of different reference planes. The electronic device includes a shared void that includes the single ended via and the return via.

Single ended vias with shared voids

Examples describe a system that may include an input engine and a proximity verification engine. The input engine may access an electronic circuit design of an electronic design automation (EDA) tool, may identify a particular signal net and a particular power net the particular signal net is referenced to in the electronic circuit design. The input engine may further identify a particular signal via in the electronic circuit design corresponding to the particular signal net and power vias in the electronic circuit design corresponding to the particular power net. In such examples, the proximity verification engine may also verify that the particular signal via is within a threshold distance from at least one of the power vias and generate a proximity alert in response to a determination that none of the power vias are within the threshold distance from the particular signal via.

Power proximity verifications for electronic circuit designs

One example includes a machine-readable storage medium encoded with instructions. The instructions are executable by a processor of a system to cause the system to receive at least one target electrical characteristic indicating a target impedance of a passive printed circuit board (PCB) structure. The passive PCB structure is a component of a serial communication channel. The instructions are executable by the processor to cause the system to divide the passive PCB structure into a plurality of elements. Each element has an input and an output. The instructions are executable by the processor to cause the system to determine at least one parameter of each element such that an image impedance of the input and the output of each element equals the target impedance.

Determining parameters of PCB structures

Examples described herein include an electromagnetic interference shield. In some examples, the electromagnetic interference shield includes a wall comprised of a conductive material. The wall may have a first surface, a second surface, and a thickness between the first surface and the second surface. The shield may include a rounded opening in the wall that creates an air passageway through the thickness of the wall. The shield may also include a first obstruction in the opening and a second obstruction in the opening. The first obstruction may span across the opening. The second obstruction may span across the opening and intersect the first obstruction. The first obstruction and the second obstruction may be waveguide structures.

Waveguide structures

A multiple-layer circuit board has a signaling layer, an exterior layer, and a ground layer. A pair of differential signal lines implemented as strip lines are within the signaling layer, and propagate electromagnetic interference (EMI) along the signaling layer. An element conductively extends inwards from the exterior layer, and as an antenna radiates the EMI propagated by the strip lines along the signaling layer outwards from the circuit board. A defected ground structure within the ground layer has a size, shape, and a location in relation to the element to suppress the EMI propagated by the strip lines to minimize the EMI that the element radiates outwards as the antenna.

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Ft. Collins, CO, United States of America

Karl Joseph Bois