Abstract: An electronic device includes a display, a fingerprint sensor, and a processing unit. The display invites a user for a first input fingerprint. The fingerprint sensor receives the first input fingerprint of the user. If the first input fingerprint matches a first pre-stored fingerprint, the display invites the user to give a second input fingerprint. The fingerprint sensor receives the second input fingerprint. If the second input fingerprint matches a second pre-stored fingerprint, the processing unit allows the user to enter the electronic device. A user authentication method for the electronic device is also provided.

Abstract: An electronic device includes a housing, a covering module, and a temperature sensing module. The housing defines a cooling opening. The temperature sensing module is connected to the covering module and adapted to detect a temperature of the housing and output a control signal to the covering module. When the temperature of the housing is lower than a pre-set temperature, the covering module closes the cooling opening. When the temperature of the housing is equal or greater than the pre-set temperature, the control signal controls the covering module to move relative to the housing and open the cooling opening.

Abstract: An exemplary air director includes a top plate, a bottom plate, side plates, an air baffle, an air inlet, and an air outlet. The bottom plate is opposite to the top plate. The plurality of side plates is connected together end to end between the top plate and bottom plate. The top plate, the bottom plate and the plurality of side plates cooperatively define a receiving chamber therebetween. The air baffle substantially vertically extends along an outer surface of one side plate of the plurality of side plates. The air inlet and the air outlet are respectively provided at opposite lateral sides of the air baffle.

Abstract: A computer system includes a computer case, a cover, and an air duct. The computer case includes a display, a housing connected to the display, a motherboard attached to the housing, and a fan module. The motherboard includes a heat generating component. An input opening and an output opening are defined in the cover. The output opening corresponds to the fan module. The air duct is mounted over the heat generating component. The air duct includes a top plate substantially parallel to the motherboard and a first side plate extending from the top plate. The first side plate is substantially perpendicular to the top plate. The first side plate defines a plurality of first airflow holes corresponding to the input opening. The top plate defines a plurality of through holes corresponding to the heat generating component.

Abstract: A heat sink assembly includes a heat sink, a first fan, and a second fan. The heat sink includes a first base contacting a first heat generating element, a first heat pipe connected to the first base, and a fin assembly. The first heat pipe is located in the fin assembly. The first fan defines a first input opening and a first output opening substantially perpendicular to the first input opening. The second fan defines a second input opening and a second output opening substantially parallel to the second input opening. The first and second input openings correspond to the fin assembly.

Abstract: A heat dissipating apparatus for a data storage device includes a mounting bracket, and a dissipating structure. The mounting bracket is configured for securing the data storage device. The dissipating structure includes a first heat dissipating panel, a second heat dissipating panel, and a plurality of heat dissipating pieces located between the first heat dissipating panel and the second heat dissipating panel. Each of the first heat dissipating panel and the second heat dissipating panel is secured to the mounting bracket. The data storage device abuts the first heat dissipating panel or the second heat dissipating panel.

Abstract: An electronic device include a metal chassis, a motherboard within the metal chassis, a central processing unit (CPU) socket attached on the motherboard, a CPU attached to the CPU socket, a heat dissipation pad attached on the CPU, and a metal heat dissipation member. The metal heat dissipation member is attached on the heat dissipation pad to transfer heat from the CPU and abuts the metal chassis to provide electro magnetic interference (EMI) shielding for the CPU.

Abstract: A circuit board includes a signal plane and a ground plane. The signal plane is configured to have a plurality of signal traces. 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 method for laying out a circuit board includes following steps. A substrate board is formed with a plurality of board sides. A ground plane, including a plurality of tiles, is provided. Each ground trace tile is defined by a plurality of ground traces. A signal plane on the substrate board has a plurality of signal traces that comprise of a plurality of straight line segments. Any one ground trace of each tile is arranged at an angle other than zero degrees relative to one determined board side. The straight line segments is applied to be mapped on the ground plane crossing one ground trace of one tile within an angle range determined by the ground traces of the tile and an adjacent diagonal line of the tile. The one ground trace and the straight line segments are applied at an angle movable in a range from 22.5° to 32.5°.

Abstract: An electronic device enclosure includes a chassis and an operating member. The chassis includes a front plate and a top plate connected to the front plate. A clipping hole is defined in the front plate. The operating member includes a positioning portion and a securing piece. The positioning portion is received so it can be slid in the clipping hole, and the securing piece is attached to the front plate.

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 all-in-one computer includes a mainframe shell, a display frame, and a power supply unit (PSU). The PSU includes an outer shell, a power supply module, and a fan module. The power supply module and the fan module are accommodated in the outer shell. The power supply module includes a main body. An axis of the fan module is perpendicular to 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: 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 assembly is provided, includes a circuit board having a first side and a second side opposite to the first side. A chip is connected to the first side of the circuit board. A first heat dissipating device is located on the first side of the circuit board. The chip is located between the first heat dissipating device and the first side of the circuit board. A second heat dissipating device abuts the second side of the circuit board, and the second heat dissipating device are secured to the first heat dissipating device to clamp the circuit board and the chip.

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 assembly includes a circuit board with two heat dissipating assemblies mounted thereon and an L-shaped back plate attached to an underside of the circuit board. Each of the heat dissipating assembly includes at least a pair of securing members at opposite corners thereof. The back plate includes a first portion and a second portion each defining at least a pair of circular protrusions corresponding to the securing members of the heat dissipating assemblies.

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 circuit board assembly includes a circuit board with two heat dissipating assemblies mounted thereon and an L-shaped back plate attached to an underside of the circuit board. Each of the heat dissipating assembly includes at least a pair of securing members at opposite corners thereof. The back plate includes a first portion and a second portion each defining at least a pair of circular protrusions corresponding to the securing members of the heat dissipating assemblies.

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.