ELECTRONIC APPARATUS

• US 20120028481A1
• Filed: 07/21/2011
• Published: 02/02/2012
• Est. Priority Date: 07/28/2010
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Saito, Hiroyuki, Saito, Kyoko
• Granted Patent: US 8,187,013 B2
• Time in Patent Office: Days
• US Class Current: 439/55
• CPC Class Codes: H05K 1/0219 Printed shielding conductors for shielding around or between signal conductors, e.g. coplanar or coaxial printed shielding conductors
• CPC Class Codes: H05K 1/0245 Lay-out of balanced signal pairs, e.g. differential lines or twisted lines
• CPC Class Codes: H05K 1/118 specially for flexible printed circuits, e.g. using folded portions
• CPC Class Codes: H05K 1/147 at least one of the printed circuits being bent or folded, e.g. by using a flexible printed circuit H05K1/148 takes precedence
• CPC Class Codes: H05K 2201/097 Alternating conductors, e.g. alternating different shaped pads, twisted pairs; Alternating components
• CPC Class Codes: H05K 2201/10189 Non-printed connector

Abstract

An electronic apparatus including a first wiring board formed having a first area, a second area, and a third area, wherein the first area is formed extending in a first direction from the third area, and the second area is formed extending in a second direction, which is opposite to the first direction, from the third area, a second wiring board connected to the first wiring board, a first connector for connection to an external device, wherein the first connector is mounted on the first area of the first wiring board, a second connector for connection to an external device, wherein the second connector is mounted on the second area of the first wiring board, and a third connector connected to the second wiring board, wherein the third connector is mounted on the third area of the first wiring board, and is formed with a first terminal array and a second terminal array facing each other, wherein on the first wiring board a first differential transmission line is formed in a region from the first connector to the first terminal array, and a second differential transmission line is formed in a region from the second connector to the second terminal array.

Claims

1. An electronic apparatus comprising:

a first wiring board formed having a first area, a second area, and a third area, wherein the first area is formed extending in a first direction from the third area, and the second area is formed extending in a second direction, which is opposite to the first direction, from the third area;

a second wiring board connected to the first wiring board;

a first connector for connection to an external device, wherein the first connector is mounted on the first area of the first wiring board;

a second connector for connection to an external device, wherein the second connector is mounted on the second area of the first wiring board; and

a third connector connected to the second wiring board, wherein the third connector is mounted on the third area of the first wiring board, and is formed with a first terminal array and a second terminal array facing each other, wherein

on the first wiring board, a first differential transmission line is formed in a region from the first connector to the first terminal array, and a second differential transmission line is formed in a region from the second connector to the second terminal array.

2. The electronic apparatus according to claim 1, wherein the first and the second differential transmission lines are formed so that, among the first terminal array, the terminal that the first differential transmission line is connected to, and among the second terminal array, the terminal that the second differential transmission line is connected to, are arranged so as not to face each other.

3. The electronic apparatus according to claim 2, wherein the first and the second differential transmission lines are formed so that, among the first terminal array, the terminal that the first differential transmission line is connected to, and among the second terminal array, the terminal that is connected to a ground, are arranged so as to face each other.

4. The electronic apparatus according to claim 1, wherein the third area has a corner shape, the first and the second differential transmission lines are wired so that the closer the differential transmission line is to the inner side of the corner shape, the more detours it has.

5. The electronic apparatus according to claim 1, wherein the first differential transmission line and the second differential transmission line are adjusted to have different impedances from each other.

6. The electronic apparatus according to claim 1, wherein the first connector is a USB connector, the second connector is a HDMI connector, and the third connector is a board-to-board connector.

7. The electronic apparatus according to claim 3, wherein the first differential transmission line is guarded on either side by a ground pattern and the second differential transmission line is guarded on both sides by a ground pattern.

8. The electronic apparatus according to claim 7, wherein the first wiring board has a rear face, and wherein a projected image of the first differential transmission line on the rear face is guarded by a ground pattern and a projected image of the second differential transmission line on the rear face is guarded by a ground pattern.

9. The electronic apparatus according to claim 1, wherein the second differential transmission line is a plurality of second differential transmission lines, each second differential transmission line having approximately the same wiring length.