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:
In a liquid crystal TV receiver, when the pins (11 to 20) of the 10-pin connector plug (115) are soldered to the pins of the pin-plug connector (110) used for connection of the coaxial cable (60) used to transmit low-frequency and RF signals to a body (120) of the TV receiver, the conversion board is provided between the pins of the 10-pin connector plug (115) and pins of the pin-plug connector (110) and the rear-side pattern of the conversion board except for the pin insertion hole (10) in which the pin (20) to which the antenna signal line (9) is to be connected is to be inserted is formed as the grounding pattern to surround at least three sides of the pin insertion holes (134A, 135A and 132A) in which the audio signal pins (14 and 15) through which low-frequency signals such as audio signals are passed and the microphone pin (12) are to be inserted, respectively. Thus, the RF characteristic and suppression of audio noises are considerably improved.
Abstract:
A circuit element has a substrate layer with first and second faces. A conductive first layer overlays the first surface, and a conductive second layer overlays the second surface. The first layer defines a pattern with a trimmable portion. The second layer defines a pattern having a first conductive element registered with at least a portion of the trimmable portion, and a second conductive element electrically isolated from first element and encompassing the first element. The second element may be a ground plane that has an aperture surrounding the first component, which serves as a shield to prevent damage to any elements beyond the second layer.
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 method and apparatus for providing thermal dissipation from a PC card is disclosed. For one embodiment of the invention, an extension portion, having a heat sink implemented thereon, is provided for a PC card. The extension portion extends beyond the PC card slot allowing thermal dissipation from the card due to air flow over the heat sink. For one embodiment of the invention, heat producing components of the PC card are identified and a thermally conductive path is provided from the components to the extension portion of the PC card.
Abstract:
A circuit structure for a package substrate or a circuit board is provided. The circuit structure has a dielectric layer with an upper surface and a lower surface, at least a first line and at least a second line. The first line is disposed on the dielectric layer on which a base of the first line is aligned with the upper surface. In addition, the second line is disposed on the dielectric layer on which a base of the second line is embedded below the upper surface. Since the second line is embedded into the dielectric layer, the distance with a reference plane is reduced and the crosstalk between the signals is further effectively reduced.
Abstract:
Embodiments of the invention provide a magnetic disk drive which has improved electrical properties owing to a reduction in the loss of transmission line, improved vibration properties owing to a reduction in the stiffness of wiring around the head, and a flat impedance in the transmission line. In one embodiment, a magnetic disk drive comprises a suspension; a magnetic head coupled with the suspension and configured to write and read information to and from a magnetic recording medium; and a transmission line disposed on the suspension to transmit writing and reading information to and from the magnetic head. The transmission line includes a writing line and a reading line, a lower conductor disposed underneath the writing line and the reading line, and an insulating layer interposed between the lower conductor and the writing and reading lines. The lower conductor comprises copper or copper-based alloy and has a thickness of substantially less than 25 nullm, desirably about 2-12 nullm, and more desirably about 5 nullm.
Abstract:
A multi-layer circuit comprises first and second transmission lines. The first transmission line includes vertically stacked bottom and middle dielectric layers. A conductive pattern is disposed between the bottom and middle dielectric layers. A bottom ground layer is in contact with a bottom surface of the bottom dielectric layer. The second transmission line is vertically stacked above the first transmission line and includes a top dielectric layer and a conductive pattern in contact with a top surface of the top dielectric layer and at least one ground layer separating a bottom surface of the top dielectric layer from the middle dielectric layer. At least one plated through hole electrically connects the first and second transmission lines. All of the dielectric layers comprise a ceramic-filled substrate with woven glass reinforcement.
Abstract:
The thermal expansion coefficient of a composite insulator layer is adjusted in order to suppress warping deformation in a multilayer printed wiring board caused by temperature change. The thicknesses and the covering ratios on the both sides of the electric conductor layer composing the multilayer printed wiring board are asymmetric with respect to the central plane. A multilayer printed wiring board is formed by laminating composite insulation layers and laminated bodies, the composite insulation layer being made of a cloth a resin impregnated into the cloth, the laminated body being composed of electric conductor layers formed by coating on a surface of the composite insulation layer. The thermal expansion coefficient of the composite insulation layer having a conductor layer with a higher covering ratio is set to be smaller than the thermal expansion coefficient of the composite insulation layer having a conductor layer with a lower covering ratio.