Abstract:
In a laminated high-frequency module, a laminate includes a plurality of dielectric layers. In a lower layer region including some of the plurality of dielectric layers, a digital circuit is provided. In an interlayer region including some of the plurality of dielectric layers, a digital circuit and an analog circuit are arranged so that they do not overlap in plan view of the laminate. In an upper layer region including some of the plurality of dielectric layers, a digital circuit is provided. Digital ICs are mounted on the surface of the uppermost dielectric layer in the upper layer region. An inner-layer ground electrode is provided on substantially an entire boundary surface between the lower layer region and the interlayer region and on substantially an entire boundary surface between the interlayer region and the upper layer region. In the interlayer region, a digital line and an inner-layer ground electrode are alternately arranged in the lamination direction.
Abstract:
A multilayer flexible printed circuit board includes a core material made of an insulating material having bendability. A solid layer is provided on one surface of the core material. The solid layer is made of an electrically conductive material to form a ground plane. A wiring layer is provided on the other surface of the core material. The wiring layer is made of an electrically conductive material having a controlled impedance. The core material, the solid layer and the wiring layer together form one set of lamination. A plurality of sets of the lamination are laminated via an insulation layer.
Abstract:
A printed circuit board is disclosed. The printed circuit board in accordance with an embodiment of the present invention can include an insulation substrate, a first ground, which is formed on one surface of the insulation substrate and connected to a first power source, a second ground, which is formed on one surface of the insulation substrate and connected to a second power source, a separator, which separates the first ground from the second ground, a first signal line, which is stacked on at least one of the first ground and the second ground, and a second signal line, which is stacked on at least one of the first ground and the second ground and is adjacent to the first signal line. The separator can include a curved part, which is bent in between the first signal line and the second signal line.
Abstract:
A process for making a multilayer circuit device having electrically isolated tightly spaced electrical current carrying traces, comprising of providing an insulative substrate having a first side coated with a layer of conductive metal intended to form a ground plane; providing a plurality of seed layer traces of a predetermined width of approximately 25 microns or less separated from each other by a predetermined distance of approximately 25 microns or less on a second side of the insulative substrate, the narrowness of such separation being essentially limited only by characteristics of the photoresist material to be deposited and developed therebetween and to withstand subsequent processing; developing ribs or barriers of photoresist forming vertical walls rising above the spaces separating the seed layer traces and defining valleys or channels thereover; depositing a desired thickness of conductive material over the seed layer traces and in the valleys or channels between the vertical walls; stripping away the resist ribs or barriers to leave conductive traces to be variously used as ground lines, signal lines and power lines; repeating the previous steps to develop a plurality of circuit boards; stacking the several circuit boards and joining them together with layers of insulative material; identifying particular ones of the traces as signal lines and other traces as power lines and/or ground lines; interconnecting at least some of the ground lines on one board to ground lines and/or ground planes on other boards by conductors extending through vias; interconnecting signal lines to signal input and output terminals; and perhaps to signal lines on other boards through vias; and interconnecting power lines to power input and output terminals, and perhaps to power lines on other boards through vias.
Abstract:
A method of manufacturing a multilayered circuit board includes the steps of: manufacturing a laminated body by laminating a prepreg of a predetermined thickness on at least one surface of a double-sided circuit board having a grounding link and a signal wiring patterned on both surfaces thereof; and applying heat and pressure to the laminated body and completing a layered structure in which the signal wiring is laid inside the prepreg at a boundary between the double-sided circuit board and the prepreg, wherein prepreg sheets of a predetermined thickness are used in a completed layered structure so that a thickness of a prepreg of the double-sided circuit board is smaller than a distance between a surface of the prepreg on a side not opposed to the double-sided circuit board and the signal wiring laid inside the prepreg.
Abstract:
A multi-layer circuit board includes first, second, third, fourth, fifth, sixth and seventh insulating substrates; first, second, third, fourth and fifth signal wiring layers; first and second ground wiring layers; and a power wiring layer. Each of the first and seventh insulating substrates has a thickness ranging from 2.5 to 6.5 mil. Each of the second, fourth and sixth insulating substrates has a thickness ranging from 3 to 9 mil. Each of the third and fifth insulating substrates has a thickness ranging from 3 to 23 mil. The first signal wiring layer has a first resistance with respect to the first ground wiring layer. The second signal wiring layer has a second resistance with respect to the first ground wiring layer and the power wiring layer. The third signal wiring layer has a third resistance with respect to the first ground wiring layer and the power wiring layer. The fourth signal wiring layer has a fourth resistance with respect to the second ground wiring layer and the power wiring layer. The fifth signal wiring layer has a fifth resistance with respect to the second ground wiring layer. The first, second, third, fourth and fifth resistances are within the range of 49.5 to 60.5 ohms.
Abstract:
Method and apparatus are disclosed for flow control over Point-to-Point Protocol (PPP) data links. A method of negotiating such flow control between two PPP peers is disclosed, along with methods for operating flow control across a PPP link. In one embodiment, flow control frames carry an IEEE802.3x MAC control frame payload—the PPP implementation repackages such frames as MAC control frames and passes them to a MAC, which performs flow control. In another embodiment, flow control frames allow flow control commands to be applied differently to different service classes such that PPP flow can be controlled on a per-class basis.
Abstract:
A backplane assembly includes a main backplane having a first power conductor, a backplane strip having a second power conductor, and connecting members disposed between the main backplane and the backplane strip. The connecting members hold the backplane strip in a fixed position relative to the main backplane and electrically connect the first power conductor and the second power conductor. In one arrangement, the connecting members include source standoffs which extend from a source area of the main backplane to the backplane strip, and target standoffs which extend from a target area of the main backplane to the backplane strip. The source and target standoffs and the second power conductor provide a current path which increases current carrying capacity from the source area to the target area above that provided by the first power conductor alone. Thus, the backplane assembly is well-provisioned for distributing high currents to circuit boards.
Abstract:
A multi-layer module for packaging an electronic component comprises an uppermost electrically conductive layer for mounting the component, a plurality of electrically insulative layers, and a plurality of electrically conductive layers disposed between the insulative layers. The electrically conductive layers form staggered placements of at least three voltage and/or ground distribution layers close to the module surface without signal wiring layers in between, and signal distribution layers comprising signal conductors. Vias form conductive paths through the insulative layers and conductive layers; the corresponding signal, voltage and ground distribution layers are electrically connected with each other and with the uppermost layer.