摘要:
Provided is a magnetic disc apparatus comprising a magnetic head for writing and reading data to and from a magnetic disc, a slider for floating up the magnetic head from the magnetic disc on rotation, a suspension having an IC chip mounting surface, for supporting the slider, a positioning mechanism for positioning a magnetic head at a predetermined position, and an IC chip mounted on the IC chip supporting surface of the suspension, wherein the rate of variation in temperature difference between opposite sides of the IC chip mounting position as a center on the IC chip mounting surface is set to be below about 3.5 K/sec. Thereby it is possible to restrain the averaged seek time for the magnetic disc from becoming longer.
摘要:
A semiconductor integrated circuit device is equipped with a cooling system which serves to cool a plurality of integrated circuit chips mounted on a circuit board. The cooling system is kept in contact with the upper surfaces of the plurality of integrated circuit chips. A chip surface arranging plate of uniform thickness is formed with apertures smaller than the integrated circuit chips mounted on the circuit board. The cooling system is fixed on the chip surface arranging plate. The upper surfaces of the integrated circuit chips are substantially kept flush by the chip surface arranging plate. Further, the integrated circuit chips are thermally joined to the cooling system so that heat generated by the integrated circuit chips is removed by the cooling system. The plurality of integrated circuit chips are joined to the chip surface arranging plate by applying a vacuum that causes suction of air through the apertures formed in the chip surface arranging plate. Thereafter, the cooling system is fixed to the chip surface arranging plate.
摘要:
A thermoplastic resin composition having well-balanced properties which comprises 95-5 weight % of polycarbonate, 5-95 weight % of polyolefin and a particular combination of additional components selected from a styrene-ethylene.propylene copolymer, a styrene-ethylene. butyrene-styrene block copolymer, an AES resin, a styrene-olefin block copolymer, an unsaturated carboxylic acid-modified polyolefin, polybutylene terephthalate, a styrene-maleic anhydride copolymer, an oxazoline ring-containing styrene copolymer a saponified olefin-vinyl ester copolymer and an epoxy group-containing styrene copolymer.
摘要:
A structure for connecting an integrated circuit chip to a wiring substrate which implements high-density packaging, high-density connection, high-speed signal transmission, and low cost. An integrated circuit is connected to a wiring substrate by means of flip-chip die bonding using an adhesive film. A direct through-hole connection is formed directly below a connecting pad so as to pass through the adhesive film and the wiring substrate. This direct through-hole connection directly connects the connecting pad to the wire. As a result of reduced area and thickness of the chip, the chip is mounted in high density, and high-density inputs and outputs are implemented by means of minute two-dimensional connections. Short wire connections directly connected to the chip permit high speed signal transmission, and high reliability is ensured by the dispersion of stress. Low-cost packaging can be effected by simple processes and facilities.
摘要:
A semiconductor device includes a semiconductor substrate having a pair of opposed main surfaces with a wiring conductor provided on one of the main surfaces; the substrate having at least one through hole extending therethrough so as to be perpendicular to the main surfaces; at least one electrically conductive pin provided on the other of the main surfaces at a position of the at least one through hole, and an adhesive filled into the at least one through hole for fixing the at least one conductive pin to the substrate, wherein the at least one conductive pin is connected electrically through the corresponding at least one through hole to the wiring conductor to transmit/receive an electrical signal to/from an external circuit.
摘要:
A clock signal supply system is disclosed for a semiconductor device with a semiconductor chip and a wiring substrate connected in flip-chip fashion and an optical waveguide interposed in the space between electrode members, in which the mutual arrangement of the electrical interconnection and the optical waveguide interconnection on the wiring substrate is not affected and can be used separately from each other for different applications, thereby improving the throughput of the interconnections as a whole. In order to distribute a very fast clock signal beyond a 1 GHz in particular without any phase deviation in the clock signal supply system, a clock distributor includes a clock oscillator, a phase adjuster for adjusting the phase at each destination of the clock signal, an optical interconnection for supplying the clock signal to the phase adjuster, a reference signal generator for generating a phase reference signal from the clock signal, and an electrical interconnection for supplying the reference signal to the phase adjuster. The clock signal is supplied by an optical interconnection having a broad frequency bandwidth, and the phase reference signal by an electrical interconnection by which the skew is controlled easily. A clock signal adjusted to high phase accuracy can thus be distributed to following destinations by the phase adjuster.
摘要:
Disclosed are a propylene polymer composition possessing excellent balance among rigidity and low warpage, resistance to deterioration caused by thermal oxidation during processing, weathering resistance, antistatic properties, and low bleeding properties, and a propylene resin composition which can easily produce molded products having excellent balance between rigidity and impact resistance (particularly low-temperature impact resistance) or heat resistance. The propylene polymer composition and the propylene resin composition comprise a propylene block copolymer consisting essentially of the following blocks (a) and (b) and having a melt flow rate of 0.1 to 200 g/10 min: block (a): a polymer block of a homopolymer of propylene or a random copolymer of propylene with a comonomer selected from the group consisting of ethylene and C4-C20 &agr;-olefins, the content of the comonomer being not more than 10% by mole; and block (b): a polymer block of a random copolymer of propylene with at least one comonomer selected from the group consisting of ethylene and C4-C20 &agr;-olefins, the content of the comonomer being 10 to 80% by mole, the average chain length of the comonomer block and the gross average chain length of the comonomer having a relationship represented by formula (I) nb≦n+1.5 (I) wherein nb represents the average chain length of the comonomer block; and n represents the gross average chain length of the comonomer.
摘要:
A laser diode driver includes a DC current source supplying DC current to a laser diode, a high frequency current source connected in parallel with the DC current source and supplying high frequency current to the laser diode. The laser diode driver further includes a circuit capable of changing the current of the DC current source when the high frequency current source is operating.