Abstract: A switching board is provided with a control circuit board including a control circuit, first mounting windows and second mounting windows, a circuit constituent including an input busbar, an output busbar and a connection busbar arranged on one surface of the control circuit board, and first and second semiconductor switching elements. The first semiconductor switching elements are arranged inside the first mounting windows and have drain terminals connected to the input busbar, source terminals connected to the connection busbar and gate terminals connected to the control circuit. The second semiconductor switching elements are arranged inside the second mounting windows and have drain terminals connected to the output busbar, source terminals connected to the connection busbar and gate terminals connected to the control circuit.

Abstract: A switching device includes a switching board with busbars, an upper case and stud bolts and nuts for fixing fastening terminals connected to wiring harnesses to the busbars. The upper case includes guide walls for guiding movements of the fastening terminals to fastening positions, and the restriction walls for restricting the rotation of the fastening terminals. The restriction walls are arranged to prevent a contact of the fastening terminal when the fastening terminal is rotated until the wiring harness comes into contact with the restriction wall.

Abstract: A switching board includes: a control circuit board that has, on a first surface thereof, a control circuit, a connection circuit, a first mounting window, and a second mounting window; a circuit structure including an input bus bar and an output bus bar are arranged on a second surface of the control circuit board; and a first and second semiconductor switching element. The first semiconductor switching element is arranged inside the first mounting window. The drain terminal, the source terminal, and the gate terminal of the first semiconductor switching element are connected respectively to the input bus bar, the connection circuit, and the control circuit. The second semiconductor switching element is arranged inside the second mounting window. The drain terminal, the source terminal, and the gate terminal of the second semiconductor switching element are connected respectively to the output bus bar, the connection circuit, and the control circuit.

Abstract: A circuit for controlling charging includes a transistor provided on a charging path between a position of a charging terminal and a position of a battery, an input voltage detecting circuit configured to detect a potential of a point on the charging path coupled to the charging terminal's side of the transistor, and a drive circuit configured to control an ON resistance of the transistor between a conductive state and a nonconductive state in response to the potential detected by the input voltage detecting circuit.

Abstract: A control circuit for controlling an output voltage of a DC/DC converter. The control circuit includes a pulse signal generation circuit which generates a pulse signal for controlling the output voltage of the DC/DC converter, and a drive signal generation circuit which generates first and second drive signals using the pulse signal such that a main switching element and a synchronous switching element are turned ON and OFF alternately at different timings. The drive signal generation circuit generates the first drive signal which has substantially the same pulse width as that of the pulse signal to improve ON-duty characteristics of the main switching element.

Abstract: A constant-voltage power supply circuit includes a constant-voltage output unit and an output current restriction unit. The constant-voltage output unit includes an output transistor and controls the transistor based on output voltage from the output transistor to maintain the output voltage constant. The output current restriction unit restricts output current of the constant-voltage output unit. When the overcurrent detection unit detects that current flowing through the output transistor that is an overcurrent flowing continuously for a predetermined time, the output current restriction unit executes an output current restriction operation. This configuration prevents the output voltage from decreasing after an overcurrent control operation.

Abstract: The present invention aims to provide a differential voltage amplifier circuit capable of preventing narrowing of an input voltage allowable range, making unnecessary the calculation of correction by an MPU or the like, reducing an influence due to a change in temperature and detecting a high-accuracy differential voltage. Upon a short circuit between input paths, an output voltage of a differential amplifier at the short circuit therebetween is held in a capacitor. Upon differential voltage amplification, a subtraction circuit section performs a process for subtraction between the output voltage held in the capacitor and a bias voltage. An output voltage is applied to a bias voltage terminal, and an output voltage obtained by multiplying the difference between input voltages by an amplification factor AV with the applied output voltage as the reference is outputted via an output terminal for a differential voltage amplifier circuit section.

Abstract: A circuit for controlling charging includes a transistor provided on a charging path between a position of a charging terminal and a position of a battery, an input voltage detecting circuit configured to detect a potential of a point on the charging path coupled to the charging terminal's side of the transistor, and a drive circuit configured to control an ON resistance of the transistor between a conductive state and a nonconductive state in response to the potential detected by the input voltage detecting circuit.

Abstract: The present invention aims to provide a differential voltage amplifier circuit capable of preventing narrowing of an input voltage allowable range, making unnecessary the calculation of correction by an MPU or the like, reducing an influence due to a change in temperature and detecting a high-accuracy differential voltage. Upon a short circuit between input paths, an output voltage of a differential amplifier at the short circuit therebetween is held in a capacitor. Upon differential voltage amplification, a subtraction circuit section performs a process for subtraction between the output voltage held in the capacitor and a bias voltage. An output voltage is applied to a bias voltage terminal, and an output voltage obtained by multiplying the difference between input voltages by an amplification factor AV with the applied output voltage as the reference is outputted via an output terminal for a differential voltage amplifier circuit section.

Abstract: A constant-voltage power supply circuit includes a constant-voltage output unit and an output current restriction unit. The constant-voltage output unit includes an output transistor and controls the transistor based on output voltage from the output transistor to maintain the output voltage constant. The output current restriction unit restricts output current of the constant-voltage output unit. When the overcurrent detection unit detects that current flowing through the output transistor that is an overcurrent flowing continuously for a predetermined time, the output current restriction unit executes an output current restriction operation. This configuration prevents the output voltage from decreasing after an overcurrent control operation.

Abstract: There are provided a DC/DC converter control circuit and a DC/DC converter system having high degree of freedom of mounting and achieving the following matters: (1) housing a DC/DC converter control circuit in a package miniaturized by reducing the number of terminals; and (2) starting-up a power saving mode in response to an input of an external control signal to a DC/DC converter system. A frequency setting terminal (RT) is connected to a resistance element RT and a switching section 1 in series, between the terminal and ground voltage. An external control signal CTL is inputted to the switching section 1. When an external control signal CTL turns off the switching section 1, connection to the ground voltage is opened and an oscillation driving section 4 does not operate. Thereby, power saving mode is kept. When the switching section 1 is turned on, connection to the ground voltage is closed and the oscillation driving section 4 starts up.

Abstract: An optical device 1 has a substrate 2, whereas bare fibers 5 exposed from a coated optical fiber tape 3 by removing a coating 4 from its middle part are secured to the upper face part of the substrate 2. In the substrate 2, a transverse groove 8 is formed obliquely with respect to an axis of the bare fibers 5 so as to traverse core parts 5a of the bare fibers. An optical member 9 for reflecting a part of signal light transmitted through the bare fibers 5 is inserted in the transverse groove 8. A support member 10 is provided on the upper side of the bare fibers 5, whereas a support surface 10a of the support member 10 is provided with photodetectors 11 for detecting light reflected by the optical member 9. The support surface 10a of the support member 10 is inclined with respect to the upper face of the substrate 2, whereby the light entrance surface 13 of each photodetector 11 is inclined by a predetermined angle with respect to the upper face of the substrate 2.

Abstract: A control circuit for controlling an output voltage of a DC/DC converter. The control circuit includes a pulse signal generation circuit which generates a pulse signal for controlling the output voltage of the DC/DC converter, and a drive signal generation circuit which generates first and second drive signals using the pulse signal such that a main switching element and a synchronous switching element are turned ON and OFF alternately at different timings. The drive signal generation circuit generates the first drive signal which has substantially the same pulse width as that of the pulse signal to improve ON-duty characteristics of the main switching element.

Abstract: An optical device 1 comprises a substrate 2, whereas bare fibers 5 exposed from a coated optical fiber tape 3 by removing a coating 4 from its middle part are secured to the upper face part of the substrate 2. In the substrate 2, a transverse groove 8 is formed obliquely with respect to an axis of the bare fibers 5 so as to traverse core parts 5a of the bare fibers. An optical member 9 for reflecting a part of signal light transmitted through the bare fibers 5 is inserted in the transverse groove 8. A support member 10 is provided on the upper side of the bare fibers 5, whereas a support surface 10a of the support member 10 is provided with photodetectors 11 for detecting light reflected by the optical member 9. The support surface 10a of the support member 10 is inclined with respect to the upper face of the substrate 2, whereby the light entrance surface 13 of each photodetector 11 is inclined by a predetermined angle with respect to the upper face of the substrate 2.

Abstract: A DC—DC converter in which no operational instability occurs and ranges of input and output voltages are wide, an electric appliance using such DC—DC converter, and a duty-ratio setting circuit in which no operational instability occurs and ranges of input and output voltages of a converter circuit can be widen in controlling the converter circuit are provided. A DC—DC converter 10 has a converter circuit 110, an output voltage detection circuit 120 and a duty-ratio setting circuit 20. An error amplifier circuit 21 compares Vref1 with Vd to output a control voltage Vfb. A pulse-width modulator circuit 25 compares a triangular-wave voltage Vct with the control voltage Vfb to output a first pulse signal PWO. A second-pulse generator circuit 26 outputs a second pulse signal PSO having a predetermined on-duty ratio.

Abstract: A DC-DC converter in which no operational instability occurs and ranges of input and output voltages are wide, an electric appliance using such DC-DC converter, and a duty-ratio setting circuit in which no operational instability occurs and ranges of input and output voltages of a converter circuit can be widen in controlling the converter circuit are provided. A DC-DC converter 10 has a converter circuit 110, an output voltage detection circuit 120 and a duty-ratio setting circuit 20. An error amplifier circuit 21 compares Vref1 with Vd to output a control voltage Vfb. A pulse-width modulator circuit 25 compares a triangular-wave voltage Vct with the control voltage Vfb to output a first pulse signal PWO. A second-pulse generator circuit 26 outputs a second pulse signal PSO having a predetermined on-duty ratio.

Abstract: There are provided a DC/DC converter control circuit and a DC/DC converter system having high degree of freedom of mounting and achieving the following matters: (1) housing a DC/DC converter control circuit in a package miniaturized by reducing the number of terminals; and (2) starting-up a power saving mode in response to an input of an external control signal to a DC/DC converter system. A frequency setting terminal (RT) is connected to a resistance element RT and a switching section 1 in series, between the terminal and ground voltage. An external control signal CTL is inputted to the switching section 1. When an external control signal CTL turns off the switching section 1, connection to the ground voltage is opened and an oscillation driving section 4 does not operate. Thereby, power saving mode is kept. When the switching section 1 is turned on, connection to the ground voltage is closed and the oscillation driving section 4 starts up.

Abstract: A charge/discharge control circuit for controlling charging and discharging of a secondary battery that includes a cell. The charge/discharge control circuit includes an overdischarge detection circuit for detecting an overdischarged state of the battery, and an overcharge detection circuit for detecting an overcharged state of the battery. A discharge control switch is deactivated in the overdischarged state. A first charge control switch is deactivated in the overdischarged state. A second charge control switch is activated in the overdischarged state. A current-limiting circuit is connected in series with the second charge control switch for limiting the charging current when charging is performed.

Abstract: A charge and discharge circuit that reduces the power consumption at charging and discharging without shortening the life of secondary batteries is described. The charge and discharge circuit includes charge current control circuits connected in parallel to the secondary batteries for performing bypass control of a charge current supplied to the secondary batteries. A potential difference detection circuit detects a voltage difference between the secondary batteries and controls the charge current control circuits in accordance with the voltage difference to selectively bypass the charge current supplied to the secondary batteries.

Abstract: A charge/discharge control circuit for controlling charging and discharging of a secondary battery that includes a cell. The charge/discharge control circuit includes an overdischarge detection circuit for detecting an overdischarged state of the battery, and an overcharge detection circuit for detecting an overcharged state of the battery. A discharge control switch is deactivated in the overdischarged state. A first charge control switch is deactivated in the overdischarged state. A second charge control switch is activated in the overdischarged state. A current-limiting circuit is connected in series with the second charge control switch for limiting the charging current when charging is performed.