Abstract: A circuit board includes a signal plane and a ground plane. The signal plane is configured to have a plurality of signal traces arranged thereon. Each of the signal traces includes a plurality of straight line segments. Each line segment extends along a path different from the others. The ground plane includes a plurality of tiles connected in an array. Each tile is formed by ground traces. The straight line segments of each signal trace mapped on the ground plane are arranged at an angle relative to any one ground trace of the tiles. The angle is defined within a range determined by one of ground traces of a tile and an adjacent diagonal line of the tile. A method for laying out such a circuit board is also provided.

Abstract: A circuit board is provided for improving signal quality, including a signal plane for a plurality of signal traces arranged thereon and a ground plane formed by a plurality of tiles connected to each other in an array. Each tile is formed by ground traces. Different line segments of a signal trace mapped on the ground plane cross ground traces of the tiles at similar angles, thereby minimizing interaction between the ground traces and the signal traces to reduce differences in impedances of the signal traces.

Abstract: A heat sink for dissipating heat from a heat source, includes a base configured to connect with a heat source, and a plurality of fins positioned on the base. A cutout is defined within the plurality of parallel fins.

Abstract: In one preferred embodiment, an objective lens actuator includes a base, a suspension apparatus mounted on the base, a holder suspended by the suspension apparatus for holding an objective lens, a voice coil motor (VCM) for driving the holder to vibrate, and a cover. The VCM includes a first yoke, a second yoke and a pair of magnets fixed on the first yoke and the second yoke respectively. The first yoke and the second yoke respectively include a first part and a second part. The cover is made of a material having a magnetic conductivity. The cover connects the first part and the second part of each of the first yoke and the second yoke.

Abstract: A heat sink assembly includes a printed circuit board, an electronic component mounted on the printed circuit board, and a heat sink mounted on the printed circuit board for dissipating heat from the electronic component. The printed circuit board includes a heat-conduction layer. The heat sink includes a base configured to contact the heat-conduction layer, and a main body extending upward from the base configured to contact the electronic component. The cross section of the base is larger than the cross section of the main body. A plurality of fins extends from the main body.

Abstract: A printed circuit board includes a base and a signal trace laid on the base. The signal trace includes a plurality of straight line segments parallel to the first fibers. The signal trace is laid on the base in such a manner that the line segments of the signal trace mapped on the base partly superpose the first fibers and partly superpose gaps between two adjacent first fibers.

Abstract: A printed circuit board assembly includes a printed circuit board, a carrier, a semiconductor chip mounted on the carrier, a plurality of tin balls soldered between the printed circuit board and the carrier for transmitting signals, and a heat sink glued to the semiconductor chip to dissipate heat. A pressing portion is formed on the bottom of the heat sink and does not make contact with the semiconductor chip. The pressing portion contacts with the periphery of the carrier to reinforce the tin balls located between the printed circuit board and the carrier.

Abstract: A button assembly for pressing a switch in a computer bezel includes a button connected to an arm. A cutout is defined in the computer bezel. The button is inserted in the cutout, and the arm is pivotably mounted on the computer bezel. A pressing portion extends outward from a side of the arm. A slanted pressing plane is formed on the pressing portion. Pressing the button moves the arm so that one end of the slanted pressing plane away from the arm contacts the switch. The switch resists the pressing portion, causing the arm to rotate so that the other end of the slanted pressing plane moves forward, thereby the slanted pressing plane entirely contacts and activates the switch.

Abstract: A printed circuit board assembly includes a printed circuit board with a heat generating component attached thereon, a base, and a thermal plate. The heat generating component comprises a side surface. The base defines a receiving room and an opening configured for access into the receiving room. The printed circuit board is received in the receiving room via the opening. The thermal plate is mounted on the base to cover the opening. A conducting piece is formed on the thermal plate and extends into the receiving room. The conducting piece includes a contacting portion extending from the thermal plate and in contact with the side surface. The conducting piece is configured for conducting heat from the heat generating component to the thermal plate. A heat dissipating hole is defined on the thermal plate in alignment with the contacting portion configured for dissipating heat from the base.

Abstract: The invention related to a method and circuit that is used to compensate for S-parameters of a passive circuit which do not satisfy passivity. The method includes the following steps: (1) getting S-parameters which do not satisfy passivity, these S-parameters being composed of an S-parameter matrix S; (2) computing matrix [S×S?], wherein matrix S? is a complex conjugate transposed matrix of the S-parameter matrix S; (3) computing the eigenvalues of the matrix [S×S?], and choosing an eigenvalue ? whose real part real(?) is the biggest; (4) computing a compensating value ?, the compensating value ? being equal to real(?)1/2×(1+?), wherein the ? is a very small positive number; and (5) dividing each of the S-parameters by the compensating value ? to get the compensated S-parameters.

Abstract: A circuit board includes a capacitor having two pins disposed thereon. A line determined by the two pins of the capacitor is not perpendicular to any of main sides of the circuit board.

Abstract: A motherboard includes a printed circuit board, a first chip and a second chip arranged on the printed circuit board in parallel. A plurality of securing holes are defined in the printed circuit board around the first chip. At least one isolating hole is defined in the printed circuit board between the second chip and a first line determined by two of the securing holes close to the second chip. Should the printed circuit board suffer an impact, damage to the chips may be effectively minimized or prevented.

Abstract: An exemplary optical disc drive apparatus includes a guide shaft configured to movably support a pickup head, and an elastically deformable member. The elastically deformable member includes a main body, and a cantilever slanting up from a middle part of a front edge of the main body. The cantilever is broad at a lower portion thereof and narrow at an upper portion thereof, and the cantilever is for resiliently pressing a corresponding end of the guide shaft. The elastically deformable member reduces a stress surface between the cantilever and the guide shaft, and lengthens the life span thereof.

Abstract: A motherboard includes a circuit board, a first chip and a second chip disposed on the circuit board. Four securing holes are defined in the circuit board around the first chip, for mounting a heat dissipating module on the first chip. Two of the securing holes determine a first line, and the other two securing holes determine a second line parallel to the first line. A center of the second chip is located along a centerline between the first and second lines. Should the circuit board suffer from an impact, damage to the chips may be effectively minimized or prevented.

Abstract: A bracket assembly for receiving at least one disk drive (40) includes an enclosure (10), a retaining bracket (30), and a connecting structure (312). The retaining bracket includes a pair of sidewalls (31, 32). The retaining bracket is attached to the enclosure at an edge of each sidewall. The connecting structure is defined in a first sidewall (31) of the sidewalls for attaching the first sidewall to the enclosure for altering a fixing relationship between the retaining bracket and the enclosure. The connecting structure is positioned near the disk drive, and away from the edge of the first sidewall. The method of assembling the bracket (30) to the enclosure (10) is also provided.

Abstract: A printed circuit board includes a base formed from a plurality of woven fibers, and signal traces laid on the base. Each of the signal traces includes at least a straight line segment. The signal traces are laid on the base in such a manner that the line segments of the signal traces mapped on the base cross the fibers at angles not equal to zero degrees.

Abstract: A circuit board is provided for improving signal quality, including a signal plane for a plurality of signal traces arranged thereon and a ground plane formed by a plurality of tiles connected to each other in an array. Each tile is formed by ground traces. Different line segments of a signal trace mapped on the ground plane cross ground traces of the tiles at similar angles, thereby minimizing interaction between the ground traces and the signal traces to reduce differences in impedances of the signal traces.

Abstract: A heat sink assembly includes a printed circuit board, a chip mounted on a top surface of the board, and a heat sink attached onto the chip of the board. The heat sink includes a base, a plurality of fins extending up from the base, and a plurality of legs extending down from the base. The legs of the heat sink contact the top surface of the board to support the heat sink.

Abstract: A motherboard includes a circuit board, a first chip and a second chip disposed on the circuit board. Four securing holes are defined in the circuit board around the first chip, for mounting a heat dissipating module on the first chip. Two of the securing holes determine a first line, and the other two securing holes determine a second line parallel to the first line. A center of the second chip is located along a centerline between the first and second lines. Should the circuit board suffer from an impact, damage to the chips may be effectively minimized or prevented.

Abstract: A circuit board assembly includes a circuit board and a semiconductor chip mounted on the board. The semiconductor chip includes a plurality of solder spots arrayed thereon in a matrix pattern. The solder spots except those located at corners of the pattern are jointed to the board via tin balls to form signal transmitting channels for transmitting signals between the board and the chip. Should the circuit board suffer impact, damage to the signal transmitting channels may be effectively minimized or prevented.