US Patent No. 10,251,274

PRINTED CIRCUIT BOARD


Patent No. 10,251,274
Issue Date April 02, 2019
Title Printed Circuit Board
Inventorship Yoshikazu Inagaki, Tokyo (JP)
Assignee CANON KABUSHIKI KAISHA, Tokyo (JP)

Claim of US Patent No. 10,251,274

1. A printed circuit board comprising:a transmitting circuit having a signal terminal for transmitting a digital signal and a ground terminal to which a ground voltage is applied; and
a printed wiring board on which the transmitting circuit is mounted, and which has at least three conductor layers stacked via insulating layers, wherein the three conductor layers are a first conductor layer, a second conductor layer and a third conductor layer,
wherein the printed wiring board comprises:
a first signal conductor pattern formed in the first conductor layer, and connected to the signal terminal of the transmitting circuit;
a resonance portion which comprises:
a ground conductor pattern formed in the second conductor layer, and connected to the ground terminal of the transmitting circuit;
a second signal conductor pattern having two conductor patterns including a first conductor pattern and a second conductor pattern, and a connecting conductor connecting between the two conductor patterns, formed in the third conductor layer and arranged in opposition to the ground conductor pattern in the second conductor layer; and
a via conductor connecting the second signal conductor pattern to the first signal conductor pattern,
wherein a surrounding area formed by surrounding the two conductor patterns by a shortest surrounding line is substantially the same as an area of the resonance portion resonating with the fundamental frequency of the digital signal,
wherein an area of the first conductor pattern is substantially equal to ½ of the surrounding area, and an area of the second conductor pattern is substantially equal to ¼ of the surrounding area, and
wherein an area between the first conductor pattern and the second conductor pattern within the surrounding area is substantially ¼ of the surrounding area.