A circuit board for use in a modular electrical connector. The circuit board has a first surface and an oppositely facing second surface. Signal pathways are provided on the first surface. The signal pathways have signal pathway ends abutting a mounting end of the circuit board. First ground pathways are provided on the first surface. The first ground pathways are positioned adjacent at least one of the signal pathways. The first ground pathways have first ground pathway ends abutting the mounting end of the circuit board. One or more second ground pathways are provided on the second surface. The one or more second ground pathways have second ground pathway ends abutting the mounting end of the circuit board. The positioning of the signal pathway ends, the first ground pathway ends and the second ground pathway ends abutting the mounting end reduces crosstalk between signal pairs.

A method of manufacturing a wiring board includes a stacking process in which N (N is an integer equal to or greater than 2) wiring layers, end portions of which include linear conductor patterns, are stacked, with the end portions superimposed, via substrates (insulating layers) provided among the wiring layers and a laminated plate is manufactured and a removing process in which the insulating layers around the end portions of the conductor patterns of the laminated plate are removed to machine the end portions into N flying leads projecting from an end face.

A cable connection structure includes: a substrate that includes: an opening; and a core wire connection electrode that is arranged on one of a principle surface and an inner layer across the opening; a cable that is arranged on a principle surface side of the substrate and includes a core wire that is electrically connected to the core wire connection electrode, the core wire connection electrode being extended so as to be separated from the substrate, the core wire connection electrode being connected to the core wire.

A connection element for an electronic component assembly includes a support, a first contact pad, and a second contact pad. The first contact pad and the second contact pad are electrically connected. A first contact conductor has a first conductor surface electrically connected to the first contact pad at a first section, and is configured to form a welded connection in a second section of the first conductor surface, and/or on the second conductor surface. The invention also relates to an electronic component assembly which includes such a connection element, and which has at least one component welded to the contact conductor.

A three-dimensional mounting structure includes a first mounting component, a second mounting component facing the first mounting component, a connecting layer disposed between the first mounting component and the second mounting component, a third mounting component, an adhesive layer, and a barrier sheet. The first mounting component includes a first end surface. The third mounting component is bonded on the first end surface through the adhesive layer. The connecting layer includes a second end surface close to the first end surface. The three-dimensional mounting structure can avoid the adhesive layer overflowing from the first end surface to the second end surface and improve the electronic product yield. A method for assembling the three-dimensional mounting structure is also disclosed.

A board-to-board connection structure includes a first circuit board, a second circuit board, and a connector. The first circuit board includes a first base layer and a first outer circuit layer. The second circuit board includes a second base layer and a second outer circuit layer. The connector electrically couples the first circuit board and the second circuit board. The connector includes a housing, a first electrical connection portion, and a second electrical connection portion. A side surface of the first circuit board includes a first conductive layer electrically coupled to the first outer circuit layer. The connector is coupled to the first conductive layer through the first electrical connection portion. The second circuit board is located in the housing, and the second electrical connection portion is electrically coupled to the second outer circuit layer.

According to one aspect of the present invention, a method of manufacturing a flexible printed interconnect board, including an insulating base film; a conductive pattern that is layered on one surface side of the base film; and a plurality of connection terminals that are fixed to a terminal connection area on one edge side of the conductive pattern, includes: fixing the plurality of connection terminals in parallel to a component fixing jig; and mounting the plurality of fixed connection terminals together with the component fixing jig.

There is a problem that contact resistance increases due to formation of an oxide film on a contact interface or biting of abrasion powder caused by micro-sliding when a contact connecting portion of a connection terminal including non-noble metal members is exposed to high temperature environment or a repetitious temperature cycle. An object of the present invention is to provide an in-vehicle electronic module that has connection reliability equivalent to that of the conventional in-vehicle electronic module even when being placed in the environment of an engine compartment and can achieve cost reduction by reducing the number of parts and assembly steps. The electronic module includes a mounting board having a circuit board on which an electronic component is mounted, and a case member for accommodating and protecting the mounting board from surrounding environment, The electronic module has a connection structure in which a portion of the circuit board is protruded to the outside through an opening of the case and inserts a board terminal into an external female connector to obtain electrical continuity, and a portion of the case member forms a connector housing that receives the female connector and isolates a space in which the board terminal is present from surrounding environment and an insulating resin member for fixing the circuit board in the case is integrally molded or joined with the circuit board.

The wired circuit board includes a conductive layer having a terminal; a gold plated layer provided on the surface of the terminal; and a solder layer provided on the surface of the gold plated layer and provided so that the terminal and the electronic component can be electrically connected. The solder layer is made of a solder composition containing Sn, Bi, Cu and/or Ni, and the thickness T.sub.solder of the solder layer relative to the thickness T.sub.Au of the gold plated layer is 16 or more.

Heat-assisted wiring traces and a conductive support substrate are respectively formed on first and second surfaces of an insulating layer. Further, connection terminals electrically insulated from the support substrate and electrically respectively connected to the heat-assisted wiring traces are formed on the second surface of the insulating layer. Each connection terminal has an element connection portion, a pattern connection portion and a spread blocking portion. When a circuit element is connected to the element connection portion of the connection terminal by solder, spreading of a molten solder applied to the element connection portion to the pattern connection portion is blocked by the spread blocking portion.