Abstract: A wiring board for solder mounting of a flat package type integrated circuit device. The flat package type integrated circuit device has a plurality of leads arranged at spaced intervals, the plurality of leads including a reference lead, an end lead, and remaining leads positioned between the reference lead and end lead.

Abstract: An optical disc apparatus includes a tracking device which positions the beam light on the recording track of an optical disc in order to carry out at least recording or reproducing of information by moving the beam light in the radial direction of the optical disc, and a detection device for obtaining a position deviation signal of the beam light by receiving reflected light from the surface of the optical disc.

Abstract: An optical disc apparatus includes a tracking device which positions the beam light on the recording track of an optical disc in order to carry out at least recording or reproducing of information by moving the beam light in the radial direction of the optical disc, and a detection device for obtaining a position deviation signal of the beam light by receiving reflected light from the surface of the optical disc.

Abstract: To accurately achieve plural-track jump operations at high speed in an optical disk apparatus, a first embodiment is provided in which an analog track jump signal is applied to move an optical beam. The analog track jump signal includes a kick pulse for acceleration, a constant pulse for constant drive, and a stop pulse for deceleration. In a second embodiment, a digital track jump signal is applied to move an optical beam. An erroneous track jump detecting circuit is additionally provided for detecting whether the optical beam correctly jumps over a designated number of tracks by comparing a number of plural track jump signals corresponding to the designated number of tracks to be jumped with the number of track signals generated when the beam jumps across a track.

Abstract: The laser diode driving circuit comprises (a) a forward current circuit for driving the laser diode for generating a light output that corresponds to the forward current, (b) a photodiode for detecting current having a value corresponding to the level of the light output, (c) a reference current source connected on the output side of said photodiode and having a prescribed reference current value, (d) inverting and amplifying means for inverting and amplifying the difference current between the photovoltaic current from said photodiode and the reference current from said reference current source, and (e) a feedback circuit for feeding back the inverted and amplified output from said inverting and amplifying means to said forward current circuit, for controlling said forward current to a current value corresponding to the reference current.

Abstract: A laser diode circuit has a photodiode which monitors the light output which is outputted by the laser diode and generates a photovoltaic current that corresponds to the level of the light output, a reference current selection device which selects a required reference current by switching among a plurality of reference current sources that are set to values of mutually different current values, and an amplifying apparatus which, by receiving a signal that corresponds to the photovoltaic current, controls the forward current of the laser diode so as to bring the photovoltaic current to a selected reference current.

Abstract: An apparatus for automatically maintaining plating current density within a predetermined range while controlling plating current to produce a desired plating thickness includes means for energizing only the number of plating cells required to maintain plating current density within the predetermined range. The total plating current required to produce the desired plating thickness is distributed among the energized plating cells. Decreases in the number of energized plating cells is made at speed values which are less by a hysteresis value than speeds at which the number of energized plating cells is increased to avoid instability due to normal speed reading variations.

Abstract: A transistor circuit has a first series circuit of first and second resistors coupled between a power source line and a circuit ground line. A second series circuit of third and fourth resistors is connected in parallel to the first series circuit. A first transistor is coupled at its collector-emitter path between the junction of third and fourth resistors and the circuit ground line. The first transistor is on-off controlled by a potential appearing at the junction of the first and second resistors. A second transistor is coupled at its collector-emitter path between an output terminal of the transistor circuit and the circuit ground line. The second transistor is on-off controlled by a potential appearing at the junction of the third and fourth resistors. The ratio of the resistance value of the first resistor to that of the second resistor is larger than the ratio of the resistance value of the third resistor to that of the fourth resistor.

Abstract: A current source circuit contains a transistor for controlling current flowing into an electric/photo converting element in a control photo coupler so that current flowing into a photo/electric converting element in the control photo coupler is equal to a predetermined ratio of an input current from an input current source. The control photo coupler and an output photo coupler are interconnected so that the current proportional to the current flowing into the electric/photo converting circuit of the control photo coupler is fed into the electric/photo converting circuit of the output photo coupler.

Abstract: An apparatus in which plating currents of a plurality of successive plating cells are normally automatically controlled in accordance with line speed to maintain uniform plating thickness, and in which the number of energized plating cells is increased or decreased in accordance with line speed to maintain plating current density within a predetermined range, includes tracking or timing facilities for progressively changing plating currents of plating cells in correspondence with movement of the strip being plated through the cells after the number of energized cells has been increased or decreased so as to reduce plating thickness variation on the portion of the strip within the plating cells at the time of the change in the number of energized cells.

Abstract: There is provided a converting circuit which functions as a transformer for an electronic circuit by electrically isolating the input and output terminals by optically coupling the input circuit system and the output circuit system through photocouplers.

Abstract: A function generator which has a plurality of operational amplifiers and a reference voltage generator circuit for applying a different reference voltage to the input terminal of each of the plurality of operational amplifiers. Also included is an LED connected between the output terminal and input terminal of each of the operational amplifiers; photo transistors which receive the emitted light of the LEDs for conversion into a current; and a load resistor which converts the current to a voltage.

Abstract: A current source circuit contains a transistor for controlling current flowing into an electric/photo converting element in a control photo coupler so that current flowing into a photo/electric converting element in the control photo coupler is equal to a predetermined ratio of an input current from an input current source. The control photo coupler and an output photo coupler are interconnected so that the current proportional to the current flowing into the electric/photo converting circuit of the control photo coupler is fed into the electric/photo converting circuit of the output photo coupler.

Abstract: A full wave rectifying circuit which has an operational amplifier, the noninverting input terminal of which is connected to ground and to the inverting input terminal of which an AC input voltage Vin is applied. Also included are two opposite polarity LEDs connected in parallel in a feedback loop between the output terminal and the inverting input terminal of the amplifier; photo transistors, which receive the emitted light of the LEDs and convert it to a current of corresponding value; and a load resistor which converts the current to voltage.

Abstract: A H-switch circuit is disclosed for rotationally driving a DC motor in a forward or reverse direction. The H-switch circuit comprises overcurrent-detecting circuits for four output transistors, which are respectively provided in order to detect the output transistor having an overcurrent, a circuit for generating an output signal upon detecting an overcurrent an integrating circuit controlled to be in a charge or discharge state according to the output signal representative of an overcurrent condition, and a circuit for turning off the output transistors when the integrating circuit is in the charge state and setting the integrating circuit to a discharge state. The charge and discharge operations of the integrating circuit are intermittently repeated until the overcurrent condition of the output transistor ends.

Abstract: An input interface circuit for a logic device which has a first transistor whose base is supplied with an input signal and whose emitter is grounded through first and second resistors and a second transistor whose base is supplied with the potential of the node of the first and second resistors and whose collector sends forth a logic signal. This input interface circuit is further provided with a third resistor connected between the second resistor and ground and a third transistor whose current path is connected in parallel to the third resistor and whose base is connected to the collector of the second transistor.

Abstract: An impedance conversion circuit is comprised of an NPN transistor of which the gate is supplied with an input voltage, a first current mirror circuit for supplying a current corresponding to the input voltage to the collector-emitter path of the NPN transistor, a second current mirror circuit which is controlled by a current supplied from the first current mirror circuit to feed back a current corresponding to the current to the gate of the transistor, a load connected between the emitter terminal of the NPN transistor and ground, and an output voltage being derived from the emitter of the NPN transistor.