An apparatus for transmitting electrical signals is disclosed. The apparatus includes a substrate and a twisted pair of conductors located on the substrate. The twisted pair of conductors has a first layer comprising conductive material, a second layer comprising nonconductive material, and a third player comprising conductive material. The first layer has a plurality of segments separated by a plurality of gaps. The second layer is positioned in said gaps and electrically insulates a portion of the segments positioned within the gaps. The third layer is positioned over the second layer. The third layer is configured to electrically connects an end of one segment to an end of another segment. The twisted pair of conductors formed by the three dimensional structure comprises two electrically isolated conductors twisted about each other.

A circuit board includes: a first substrate including a first through hole, a first metal layer formed over an inner wall of the first through hole, and a first conductive composite resin provided on an inner side of the first metal layer of the first through hole; and a second substrate stacked together with the first substrate and including a second through hole that faces the first through hole and has a first open end which is provided on a side of the first through hole and is located on the inner side of the first metal layer, and a second conductive composite resin that is provided in the second through hole and is coupled to the first conductive composite resin.

A circuit board pad mounting orientation system includes a board. A signal transmission line is included on the board. A plurality of connector pads are positioned on the board. At least one connector pad receives the signal transmission line adjacent a first end of that connector pad. At least one connector pad includes a second end that provides a reduction in a width of that connector pad to indicate a mounting orientation for coupling to the connector pad that receives the signal transmission line. In a specific example, a first connector pad receives the signal transmission line, includes the first end, and includes the second end that is opposite the first connector pad from the first end and that provides the reduction in the width of the first connector pad to indicate the mounting orientation for coupling to the first connector pad.

A method for manufacturing a flexible printed circuit board, comprising: providing a flexible printed circuit substrate; defining first through holes and second through holes through the flexible printed circuit substrate; and forming first conductive pillars and second conductive pillars; and defining first grooves by removing a portion of each first conductive pillar and defining second grooves by removing a portion of each second conductive pillar; the first grooves and the second grooves are defined from an outer surface of the flexible printed circuit board on the second conductive pattern layer side to a surface of the second conductive pattern layer away from the first conductive pattern layer; each of the first grooves is aligned with and corresponds to one first conductive pillar, and each of the second grooves is aligned with and corresponds to one second conductive pillar.

A wiring structure of a head suspension including a flexure that supports a head and is attached to a load beam applying load onto the head, includes write wiring and read wiring formed on the flexure and connected to the head, each having wires of opposite polarities and further including a stacked interleaved part which includes segments electrically connected to the respective wires of the write wiring, the segments stacked on and facing the wires through an electrical insulating layer so that the facing wire and segment have opposite polarities, is manufactured by a wiring step, an insulating layer forming step and a stacked interleaved part forming step.

A flexible printed circuit board includes: a board having a top surface and a back surface; a signal line on the top surface; a ground line on the back surface and overlapping with the signal line; a first signal terminal extending along a first direction in the top surface, the first signal terminal including a first via-hole and electrically connected with the signal line; a first ground terminal next to the first signal terminal along a second direction intersecting the first direction on the top surface, the first ground terminal including a second via-hole electrically connected with the ground line; and a second ground terminal next to the first signal terminal in a side opposite to the first ground terminal along the second direction on the top surface, the second ground terminal including a third via-hole electrically connected with the ground line.

A flexible printed circuit board (PCB), a method for manufacturing the flexible PCB, and a PCB structure having the flexible PCB are disclosed. A flexible printed circuit board includes a first conductive pattern layer, a second conductive pattern layer, a plurality of first conductive pillars, and a plurality of second conductive pillars. Each of the plurality of first conductive pillars electrically connects to the first conductive pattern layer and is spaced from the second conductive pattern layer, and a plurality of second conductive pillars electrically connects to the second conductive pattern layer and is spaced from the first conductive pattern layer. The plurality of first conductive pillars and the plurality of second conductive pillars are exposed from one surface of the flexible printed circuit board to form a plurality of electrical contact pads.

A printed circuit board includes a plurality of layers including attachment layers and routing layers; and via patterns formed in the plurality of layers, each of the via patterns including first and second signal vias forming a differential signal pair, the first and second signal vias extending through at least the attachment layers; ground vias extending through at least the attachment layers, the ground vias including ground conductors; and shadow vias located adjacent to each of the first and second signal vias, wherein the shadow vias are free of conductive material in the attachment layers. The printed circuit board may further include slot vias extending through the attachment layers and located between via patterns.

Disclosed herein are printed circuit boards with embedded solenoid filters through which signal traces pass to filter unwanted noise and electromagnetic interference. A printed circuit board comprises a least three layers, a solenoid embedded within the at least three layers, and at least one trace extending through the solenoid. The insertion loss characteristics of the solenoid filter can be tuned by modifying the number of turns in the solenoid(s) and the width of the solenoid(s). The solenoid filter may comprise multiple solenoids connected in series, with adjacent solenoids having opposite wind directions. Surface components may be included on the board to tune the insertion loss further.

A wiring structure of a head suspension including a flexure that supports a head and is attached to a load beam applying load onto the head, comprises write wiring and read wiring formed on the flexure and connected to the head, each having wires of opposite polarities, and further including a stacked interleaved part includes segments electrically connected to the respective wires of the write wiring, the segments stacked on and facing the wires through an electrical insulating layer so that the facing wire and segment have opposite polarities.