Abstract:
An exemplary printed circuit board includes a substrate, a differential transmission line, and at least two weld pad pairs. The differential transmission line and the at least two weld pad pairs are disposed on the substrate. The differential transmission line includes two parallel signal conductors disposed on the substrate. Each of the two signal conductors is electrically connected to an edge of one of the weld pads of a respective pair of the at least two weld pad pairs. Thereby, the two signal conductors of the differential transmission line can extend in the same distance anywhere, particularly in the position where the two signal conductors pass the two weld pad pairs. As a result, the coupling performance and the capability of the differential transmission line to resist electromagnetic interference are both enhanced.
Abstract:
A wiring substrate of the present invention includes such a structure that a plurality of connection pads and leading wiring portions connected to the plurality of connection pads respectively are arranged to an insulating layer of a surface layer side, and the leading wiring portions are arranged to be bended from the connection pads, and a solder layer to protrude upward is provided on the connection pads respectively. A solder on the leading wiring portions moves to the bend portion side, and thus the solder layer to protrude upward is formed on the connection pads.
Abstract:
A strengthened semiconductor die substrate and package are disclosed. The substrate may include contact fingers formed with nonlinear edges. Providing a nonlinear contour to the contact finger edges reduces the mechanical stress exerted on the semiconductor die which would otherwise occur with straight edges to the contact fingers. The substrate may additionally or alternatively include plating traces extending at an angle from the contact fingers. Extending at an angle, at least the ends of the plating traces at the edge of the substrate are covered beneath a lid in which the semiconductor package is encased. Thus, when in use with a host device, contact between the ends of the plating traces beneath the lid and contact pins of the host device is avoided.
Abstract:
A circuit board includes a signal plane and a ground plane. The signal plane is configured to have a plurality of signal traces arranged thereon. Each of the signal traces includes a plurality of straight line segments. Each line segment extends along a path different from the others. The ground plane includes a plurality of tiles connected in an array. Each tile is formed by ground traces. The straight line segments of each signal trace mapped on the ground plane are arranged at an angle relative to any one ground trace of the tiles. The angle is defined within a range determined by one of ground traces of a tile and an adjacent diagonal line of the tile. A method for laying out such a circuit board is also provided.
Abstract:
A wiring substrate of the present invention includes such a structure that a plurality of connection pads and leading wiring portions connected to the plurality of connection pads respectively are arranged to an insulating layer of a surface layer side, and the leading wiring portions are arranged to be bended from the connection pads, and a solder layer to protrude upward is provided on the connection pads respectively. A solder on the leading wiring portions moves to the bend portion side, and thus the solder layer to protrude upward is formed on the connection pads.
Abstract:
One end of a power-supply bus is connected to a power supply through a ferrite bead. The power-supply bus is connected to power-supply terminals. The power-supply terminals are connected at positions in such a manner that a terminal with a higher intensity is connected closer to the other end of the power-supply bus. Ground terminals are connected to ground. Capacitors are bypass capacitors or decoupling capacitors, for example, and connected between respective power-supply terminals and ground.
Abstract:
A printed circuit board includes a group of pads suitable to be soldered to a respective group of solder-balls of a device. Each pad of the group has a crack initiation point on its perimeter at a location where cracks in a solder-ball are anticipated to start after that solder-ball is soldered to that pad. For a pad of that group having a microvia located therein, a center of that microvia is located farther than a center of that pad from its crack initiation point. For a pad of that group having a trace merging along a portion of its perimeter, that portion does not include a vicinity of that crack initiation point.
Abstract:
A method of routing or laying out signal traces on printed wire or circuit board in order to improve signal transmission quality. The method includes routing a given signal trace such that it is electrically connected to a rectangular corner of a substantially wider component pin pad and forms an angle of approximately 135 degrees with the proximate sides of the pad, thereby minimizing the impedance discontinuity at the interface or junction of the signal trace and pad and hence minimizing the reflection of the digital signal at the interface or junction.
Abstract:
A strengthened semiconductor die substrate and package are disclosed. The substrate may include contact fingers formed with nonlinear edges. Providing a nonlinear contour to the contact finger edges reduces the mechanical stress exerted on the semiconductor die which would otherwise occur with straight edges to the contact fingers. The substrate may additionally or alternatively include plating traces extending at an angle from the contact fingers. Extending at an angle, at least the ends of the plating traces at the edge of the substrate are covered beneath a lid in which the semiconductor package is encased. Thus, when in use with a host device, contact between the ends of the plating traces beneath the lid and contact pins of the host device is avoided.
Abstract:
A circuit board has, in a first signal layer, a signal conductor having a relatively small width and a contact pad having a relatively large width. The relatively large width of the contact pad combined with the relatively narrow signal conductor creates an impedance mismatch between the contact pad and the signal conductor. The circuit board has, in a second signal layer, a ground plane separated from the first signal layer by a nonconductive layer. The circuit board defines an opening in the second signal layer underneath the contact pad. The presence of the ground plane underneath the contact pad typically affects the impedance of the contact pad. The opening in the second signal layer removes a portion the ground plane relative to the contact pad and, therefore, reduces the impedance mismatch between the contact pad and the signal conductor. Such reduction in the mismatch of the impedances between the contact pad and the signal conductor minimizes signal reflection of a signal transmitted through the signal conductor and across the contact pad.