Abstract:
A heat sink assembly includes a printed circuit board, a socket attached on a top surface of the board for receiving a chip, and a heat sink attached onto the chip of the board. The socket includes a plurality of legs integrally extending down from a bottom surface of the socket. The legs contact the top surface of the board to support the socket on 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.
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:
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 Ψ whose real part real(Ψ) is the biggest; (4) computing a compensating value ξ, the compensating value ξ being equal to real(Ψ)1/2×(1+ε), wherein the ε is a very small positive number; and (5) dividing each of the S-parameters by the compensating value ξ to get the compensated S-parameters.
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:
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 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 chip packaging process is provided. First, a cavity is formed on a heat sink. A first encapsulant is formed on the bottom of the cavity. A circuit substrate is disposed over the heat sink. The circuit substrate has an opening that corresponds in position to the cavity. Thereafter, a chip is disposed on the first encapsulant and the chip is electrically connected to the circuit substrate. Finally, a compound is deposited over the first encapsulant and the chip to form a chip package. The chip package is warp resistant and the chip packaging process increases overall production yield.
Abstract:
A chip package structure comprises a carrier, a chip and an underfill. The chip has an active surface on which a plurality of bumps are formed. The chip is flip-chip bonded onto the carrier with the active surface facing the carrier, and is electrically connected to the carrier through the bumps. The underfill is filled between the chip and the carrier. A portion of the underfill near the chip serves as a first underfill portion. The portion of the underfill near the carrier serves as a second underfill portion. The Young's modulus of the first underfill portion is smaller than the Young's modulus of the second underfill portion. The second underfill portion can be optionally replaced with a selected encapsulation. The selected encapsulation covers the chip and the carrier around the chip.
Abstract:
A semiconductor package includes spacers, a chip, bonding wires, contacts, and an encapsulant. The chip is disposed on the spacers. The bonding wires are electrically connected to the chip, and the contacts are electrically connected to the bonding wires. The contacts are electrically connected to an external circuit board. The encapsulant encapsulates the spacers and the active and back surfaces of the chip so as to lower the thermal stress of the chip.
Abstract:
A conductive jointing structure that is applied on a chip with multitude of connection pads has a first conductive structure and a second conductive structure. The first conductive structure is allocated on one of the contact pads. The second conductive structure made of lead-free based material is consisted of multitude of stacked portions with respectively different modulus. The portion contacting the first conductive structure is with small modulus, while the portion away from the first conductive structure is with large modulus.