公开(公告)号：US20220030706A1

公开(公告)日：2022-01-27

申请号：US17380079

申请日：2021-07-20

Applicant: Hitachi, Ltd.

Inventor： Goroh HAMAMOTO ,  Yutaka UEMATSU ,  Yohei OSHIMA ,  Maya HYAKUDOMI

IPC: H05K1/02 ,  H05K3/28

Abstract: In a printed wiring board, one transmitting circuit and N (N is an integer of 3 or more) receiving circuits are coupled by a multi-point wiring. First to N-th branch points are provided in sequence in the multi-point wiring having one end coupled to the transmitting circuit. Wirings branched at the respective branch points are coupled to the respective receiving circuits. Here, a wiring length from a coupling point of the transmitting circuit to a first branch point is configured to be longer than a wiring length from the first branch point to the second branch point. Wiring lengths between the adjacent branch points at and after a second branch point are configured to be shorter than the wiring length from the first branch point to the second branch point.

公开(公告)号：US20240080979A1

公开(公告)日：2024-03-07

申请号：US18223679

申请日：2023-07-19

Applicant: Hitachi, Ltd.

Inventor： Goro HAMAMOTO ,  Keisuke YAMAMOTO ,  Yutaka UEMATSU ,  Shinsuke ONOE ,  Yohei OSHIMA

IPC: H05K1/11 ,  H05K1/02

CPC classification number: H05K1/115 ,  H05K1/0215 ,  H05K2201/10159

Abstract: There is provided a printed wiring board including an outermost conductive layer that includes a plurality of conductive pads, a first conductive layer that includes a first inner-layer wiring and is stacked on the conductive layer, a second conductive layer that includes a second inner-layer wiring and is stacked on the conductive layer and the first conductive layer, a first signal via that connects one of the conductive pads and the first inner-layer wiring with each other, a second signal via connecting another one of the conductive pads and the second inner-layer wiring with each other, and a stitching via that is connected to a ground. The first inner-layer wiring and the second inner-layer wiring form a common wiring route in which the first inner-layer wiring and the second inner-layer wiring are stacked and disposed in a connection area in which the conductive pads are arranged.