Abstract: A printed wiring board includes a bridge located in a surface layer, a noise absorber located on the bridge, a plurality of grounds directly connected or high-frequency-connected to the bridge, a first device using one of the plurality of grounds as a reference potential, a second device using one of the plurality of grounds other than the ground for the first device as a reference potential, and a high-speed signal line that connects the first device and the second device. The high-speed signal line is routed through a layer adjacent to the bridge in a layer direction of the printed wiring board to form a transmission line structure.

Abstract: A printed wiring board, which may be included in an electronic apparatus, includes a pair of signal pads including a first signal pad and a second signal pad formed on a front side thereof and configured to transmit differential signals, a ground pad formed at a position in proximity to the pair of signal pads, and a via configured to connect the ground pad to a ground pattern formed either on a back side or on an inner layer of the printed wiring board directly or via a lead wire led out from the ground pad. The via is located at a substantially equal position spaced away from the first signal pad and the second signal pad.

Abstract: A printed wiring board includes a bridge located in a surface layer, a noise absorber located on the bridge, a plurality of grounds directly connected or high-frequency-connected to the bridge, a first device using one of the plurality of grounds as a reference potential, a second device using one of the plurality of grounds other than the ground for the first device as a reference potential, and a high-speed signal line that connects the first device and the second device. The high-speed signal line is routed through a layer adjacent to the bridge in a layer direction of the printed wiring board to form a transmission line structure.

Abstract: An electromagnetic field analysis apparatus includes an information input device configured to input information as to wirings and components of an analysis object and a modeling device configured to generate a simulation model of the analysis object based on the inputted information as to wirings and components of the analysis object. A model simplification device simplifies the simulation model into a simplified simulation model by dividing the analysis object according to the simulation model into a plurality of cells and thinning out, when a plurality of elements are included in a cell, the plurality of elements.

Abstract: A noise injection apparatus for injecting noise to a printed circuit board is disclosed that includes a signal generator that generates noise, a coaxial cable having one end connected to an output of the signal generator, and a probe that is connected to another end of the coaxial cable and is configured to convey the noise generated by the signal generator to a power supply and a ground pin of a device element of the printed circuit board via the coaxial cable.

Abstract: A printed wiring board, which may be included in an electronic apparatus, includes a pair of signal pads including a first signal pad and a second signal pad formed on a front side thereof and configured to transmit differential signals, a ground pad formed at a position in proximity to the pair of signal pads, and a via configured to connect the ground pad to a ground pattern formed either on a back side or on an inner layer of the printed wiring board directly or via a lead wire led out from the ground pad. The via is located at a substantially equal position spaced away from the first signal pad and the second signal pad.

Abstract: A testing method for measuring electromagnetic interference of a noise on a to-be-tested printed circuit board, has the steps of: a) injecting a signal simulating an expected noise of a predetermined device mounted on the to-be-tested printed circuit board, into the to-be-tested printed circuit board, in a condition in which at least the predetermined device is not actually mounted on the to-be-tested printed circuit board; and b) measuring electromagnetic interference of the signal.

Abstract: A design rule for a printed wiring board is provided. A conductive layer and a pad are separate from each other in a distance defined by the design rule, which sufficiently prevents the capacitance coupling between the conductive layer and the pad.

Abstract: A noise injection apparatus for injecting noise to a printed circuit board is disclosed that includes a signal generator that generates noise, a coaxial cable having one end connected to an output of the signal generator, and a probe that is connected to another end of the coaxial cable and is configured to convey the noise generated by the signal generator to a power supply and a ground pin of a device element of the printed circuit board via the coaxial cable.

Abstract: A design rule for a printed wiring board is provided. A conductive layer and a pad are separate from each other in a distance defined by the design rule, which sufficiently prevents the capacitance coupling between the conductive layer and the pad.

Abstract: A testing method for measuring electromagnetic interference of a noise on a to-be-tested printed circuit board, has the steps of: a) injecting a signal simulating an expected noise of a predetermined device mounted on the to-be-tested printed circuit board, into the to-be-tested printed circuit board, in a condition in which at least the predetermined device is not actually mounted on the to-be-tested printed circuit board; and b) measuring electromagnetic interference of the signal.

Abstract: An electromagnetic field analysis apparatus includes an information input device configured to input information regarding wirings and components of an analysis object and a modeling device configured to generate a simulation model of the analysis object based on the inputted information regarding the wirings and the components of the analysis object. A model simplification device simplifies the simulation model into a simplified simulation model by dividing the analysis object according to the simulation model into a plurality of cells and thinning out, when a plurality of elements are included in a cell, the plurality of elements included in the cell such that difference between a calculation result of an electromagnetic field distribution of the analysis object according to the simplified simulation model and a measurement result of actual electromagnetic field distribution of the analysis object is minimal.