Canon Kabushiki Kaisha

Satoshi Sugimoto

Shinichi Nishimura

Hideho Inagawa

Seiji Hayashi

Daishiro Sekijima

Yoshitaka Kawase

An interposer of a first semiconductor package includes a power supply wiring for a second semiconductor element, the power supply wiring including a land provided in one surface layer, and a power supply pattern provided in an inner layer and electrically connected to the land, the power supply wiring further including a larger number of lands than the land, which are provided in another surface layer and electrically connected in parallel to the power supply pattern. In a stacked semiconductor device, this configuration can improve the quality of power supply to the second semiconductor element to secure signal processing operation while preventing an increase in inductance caused by the bending of a power supply path in a power supply wiring of a printed wiring board or by a deviation of connection intervals.

Stacked semiconductor device and printed circuit board

A cable arranging structure for exchanging electric signals between a pair of printed circuit boards includes at least a pair of electrically conductive members adapted to arrange the cable between them over the entire length thereof. The electrically conductive members show an electric potential substantially equal to that of the ground. Such a structure requires only the two electrically conductive members to be rigidly secured so that radiant noises generated by the cable can be effectively suppressed by means of the structure without the need of deforming the cable.

Cable arranging structure

An image reading apparatus includes a movable image-capturing printed circuit board including an image device, and a controlling printed circuit board which is fixed to the image reading apparatus and which controls the driving of the image device. Both printed circuit boards include connectors. When electric connection is established between the connectors, signal transmission and reception is performed. The connectors are connected only in a predetermined position. This can eliminate the need for using cable wires. Thus, a simplified structure can reduce emission generated by using cable wires to transmit a driving signal for the image device and a read image signal.

Image reading apparatus

A printed-wiring board is incorporated into an electronic device housing constructed of a conductive member, and has a ground pattern. A metal plate having a size equal to or larger than the printed-wiring board is disposed in a position facing to the printed-wiring board. The metal plate has a characteristic impedance corresponding to an electric characteristic and a relative position to the printed-wiring board. A connecting member electrically connects the ground pattern of the printed-wiring board to the metal plate, and includes an impedance element having a value substantially equal to the characteristic impedance between the printed-wiring board and the metal plate. An occurrence of radiant noises caused by standing-waves etc. is thereby prevented. A conductive layer having the ground pattern of the printed-wiring board may be connected to another conductive layer provided instead of the metal plate and including a conductive member of which an area is substantially equal to the former conductive layer, with an impedance element interposed between these conductive layers.

Printed-wiring board and electronic device having the same wiring board

A ground pattern of a printed circuit board of an electronic instrument is connected with a conductive part of a housing of the instrument by a series combination of components respectively having the inductive nature and capacitive nature, or by a series combination of components respectively having the resistive nature and capacitive nature, or by a series combination of components respectively having the inductive nature, capacitive nature, and resistive nature. In this way the impedance can be adjusted against frequency so as to be ready for the frequency where the standing wave appears, the resonance frequency of LC series circuit, and harmonic frequencies of electric current flowing on the circuit board. In another arrangement, the ground pattern of a printed circuit board is connected with the conductive part of the housing of instrument through a plurality of separate connection paths with different impedances.

Growing community of inventors

Kanagawa, Japan

Satoshi Sugimoto