Abstract:
A conductive fabric including a plurality of conductive elements defining an alternating sequence of segments and cross-over regions. Within each of the segments, the conductive elements are arranged substantially in parallel; within each of the cross-over regions located between two adjacent segments, the conductive elements are permuted so as to allow the position occupied by at least one of the conductive elements to be different in each of the two adjacent segments. Between a pair of reference segments, each of the conductive elements experience coupling with respect to a subset of said conductive elements other than itself, the coupling experienced by each of the conductive elements being substantially identical.
Abstract:
In a printed wiring board in which wiring patterns for interconnecting a plurality of integrated circuits (ICs) operating with synchronizing signals, in order to make signal transmission times between a plurality of IC's the same, consecutively formed pairs of an inductance pattern and a capacitive pattern, are constructed at each of wiring patterns for interconnecting a plurality of IC's. By changing the shapes of the inductance pattern and the capacitive pattern, it is possible to adjust signal propagation velocities and signal transmission times.
Abstract:
A through hole 2 in a circuit board 1 and to be joined to a lead 5 in a surface mounting component 6 is prepared from a material such as nickel, and palladium having a thermal conductivity equal to or less than 100 W/m.K, the circuit board 1 involving a alloy layer composed of at least a member selected from elements of solder 8, a pad 7, and the lead 5 in a solder joined site of the lead 5 and the pad 7, whereby a quantity of heat transmitted to the joined site via the through hole 2 is reduced at the time when wave-soldering is applied to the back of the circuit board 1 after the surface mounting component 6 was mounted, so that the joined site is maintained at a temperature equal to or less than a melting point of the alloy layer, and hence, exfoliation in an interface of the joined site is prevented, and reliability in the joint of the lead 5 and the pad 7 is elevated.
Abstract:
Techniques for reducing the number of layers in a multilayer signal routing device are disclosed. In one particular exemplary embodiment, the techniques may be realized as a method wherein the multilayer signal routing device has a plurality of electrically conductive signal path layers for routing a plurality of electrical signals thereon. The method may comprise forming a plurality of electrically conductive vias in the multilayer signal routing device for electrically connecting at least two of the plurality of electrically conductive signal path layers, wherein the plurality of vias are arranged so as to form at least one channel in at least one other of the plurality of electrically conductive signal path layers. The method may also comprise grouping at least a portion of the plurality of electrical signals based at least in part upon their proximity to the at least one channel so that they may be efficiently routed therein.
Abstract:
The respective ends of input wiring on a printed wiring board of a signal transmission circuit are connected to an input terminal section and a transistor. The respective one terminals of a first capacitor and a first resistor are connected to the input wiring. A leading-side transmission path from a connection point with the first capacitor to a connection point with the input terminal section is formed by only a conductive pattern. An intermediate transmission path from the connection point with the first capacitor to a connection point with the first resistor includes two or more through holes or via holes. The intermediate transmission path is placed near grounding wiring on the printed wiring board. When one terminal of a second capacitor is connected to the intermediate transmission path, a transmission path between the respective connection points with the two capacitors includes one or more through holes or via holes.
Abstract:
A computer motherboard is described. That motherboard includes a memory controller and a memory section. A first trace couples the memory controller to the memory section, and a second trace couples the memory controller to the memory section. The first trace is joined with the second trace at the memory controller, the second trace is routed in parallel with the first trace, and the second trace is longer than the first trace. Also described is a computer system that includes this motherboard and a memory card.
Abstract:
An apparatus and method are described for reducing the timing skew on a printed circuit board including a plurality of conductive traces interconnecting a first node and a second node. At least one section is removed from at least one printed circuit board trace to thereby sever a trace and prevent signals passing from the first node to the second node from following the severed trace. In this manner, signal path length can be adjusted to reduce timing skews in the circuit. Sections are removed from the traces by using a laser, CVD, a router, a plasma or by passing sufficient current through weakened areas of the traces.
Abstract:
A printed circuit board (PCB) via, providing a conductor extending vertically between microstrip or stripline conductors formed on separate layers of a PCB, includes a conductive pad surrounding the conductor and embedded within the PCB between those PCB layers. The pad's shunt capacitance and the magnitudes of capacitances of other portions of the via are sized relative to the conductor's inherent inductance to optimize frequency response characteristics of the via.
Abstract:
A substrate supporting a plurality of interconnecting patterns arranged in matrix is cut at a position at least between adjacent columns of the interconnecting patterns. A plurality of positioning marks are formed on the substrate and arranged on a straight line between adjacent columns of the interconnecting patterns. Cutting of the substrate is performed by using the positioning marks as reference.