Patent application number | Description | Published |
20100033101 | Electronic Ballast with Multimode Lamp Power Control - A control means has an adjustment function in a microprocessor to adjust variations in an output to a discharge lamp due to variations in components by correcting a duty ratio of a PWM signal for varying an operating frequency of an inverter circuit so that a detected value of a second detection circuit falls within a target range. The microprocessor switches paths to transmit the PWM signal between a path passing through a feedback circuit and a path passing through a voltage follower circuit by switches a switch circuit to supply the signal through the path passing through the voltage follower circuit in adjusting output variations in the preheating mode and the starting mode. | 02-11-2010 |
20100270932 | FAULT DETECTION AND SHUTDOWN CONTROL CIRCUITS AND METHODS FOR ELECTRONIC BALLASTS - An electronic ballast is capable of inhibiting ballast shutdown caused by erroneously determining a fault condition. The ballast includes a DC power supply circuit for outputting DC power, a power conversion circuit that appropriately converts DC power outputted by the DC power supply circuit and outputs it to a discharge lamp, a DC voltage droop detection circuit for determining existence/absence of a fault condition in the DC power supply circuit | 10-28-2010 |
20100270949 | ELECTRONIC BALLAST WITH INPUT VOLTAGE FAULT CONTROL - An electronic ballast includes circuitry to prevent a switch from being damaged in the case where an abnormality occurs in an output voltage of an input power supply. A DC power supply control circuit has a zero current detection circuit that, when a current through an inductor becomes equal to or less than a predetermined current value, outputs a zero signal. A peak current detection circuit, when current through a switch the DC power supply circuit becomes equal to or greater than the predetermined current value, outputs a peak signal. A first drive circuit turns on the switch according to the zero signal, and turns off the switch Q | 10-28-2010 |
Patent application number | Description | Published |
20130026949 | LIGHTING DEVICE AND ILLUMINATION APPARATUS USING SAME - An LED lighting device includes: a power source unit for supplying the DC output voltage to a light-emitting diode; a control unit for adjusting the DC output voltage; and a control power source unit for supplying a control power to the control unit. The control power source unit generates the control power with the DC output voltage and has: a current-limiting resistor for limiting an electric current that flows from the power source unit to the control unit; a constant voltage unit for converting a voltage to be applied to the control unit through the current-limiting resistor unit to a constant voltage; and a switching unit for switching a resistance value of the current-limiting resistor unit among a plurality of resistance values. | 01-31-2013 |
20130154497 | LIGHTING DEVICE AND ILLUMINATION APPARATUS INCLUDING SAME - A lighting device includes a voltage conversion circuit having at least a switching element connected to a positive potential side of the output terminals of the DC power source unit, and a drive unit which outputs a drive signal to the switching element. The drive unit has a first impedance element with a first impedance which is determined based on a power consumed by the drive unit before a predetermined time has elapsed after a control power source is supplied. A control capacitor for use in generating the drive signal is charged when the switching element is turned off during an on/off operation of the switching element. The lighting device further includes a second impedance element with a second impedance having a resistance component, which is arranged in a path in which the control capacitor can be charged in DC when the switching element does not perform the on/off operation. | 06-20-2013 |
20130207563 | POWER SUPPLY DEVICE AND LIGHTING DEVICE AND LIGHTING FIXTURE USING THE SAME - A power supply device comprises: a DC power supply section that outputs a DC voltage; a voltage conversion section that supplies a DC power to a load by ON/OFF drive of a switching element; a resistor; a control section that performs the ON/OFF drive of the switching element; and an auxiliary winding. The control section comprises: a calculation section that calculates a drive period of the switching element; a count section compares a calculation result obtained in the calculation section with an upper limit value of the drive period; and a flip-flop. When the calculation result is shorter than the upper limit value, the flip-flop sets the drive period, using the calculation result. When the calculation result is longer than the upper limit value, the flip-flop sets the drive period, using the upper limit value. | 08-15-2013 |
20140009077 | LED LIGHTING DEVICE AND ILLUMINATING APPARATUS USING THE SAME - An LED lighting device includes: a resistor R | 01-09-2014 |
Patent application number | Description | Published |
20140028308 | MAGNETIC SENSOR DEVICE - A magnetic sensor device includes a first magnet and a second magnet that are disposed on mutually opposing sides of a conveyance path, and one of poles of the first magnet faces an opposite pole of the second magnet. The first magnet and the second magnet generate a cross magnetic field whose strength in a spacing direction, which is orthogonal to a conveying direction, is within a predetermined range. An AMR element is located in a magnetic field in which the strength of the cross magnetic field in the spacing direction is within a predetermined range, and detects, as change in a resistance value, change in the cross magnetic field caused by an object to be detected. A multilayer board outputs the change in the resistance value detected by the AMR element to a processing circuit. | 01-30-2014 |
20140347884 | LIGHT-SOURCE DEVICE AND REFLECTOR-SUPPORT STRUCTURE - A light source device includes: a rod-shaped light source or an array light source extending in a main scanning direction; a reflector that is placed opposite the rod-shaped light source or the array light source, extends in the main scanning direction, and reflects light output from a side face of the rod-shaped light source or the array light source; and a plurality of reflector supports that are arranged at an interval along the main scanning direction and support the reflector. | 11-27-2014 |
20140354385 | MAGNETIC CIRCUIT - A magnetic circuit, provided with a short magnet and short magnet that are arranged in an array, and a yoke and a yoke provided so as to sandwich the short magnet and short magnet. The short magnet and short magnet, are arranged, that have a space between them that is a predetermined gap or less in the arrangement direction of the array respectively. In addition, the short magnet and short magnet are arranged so that one magnetic pole is located on the side toward one of the pair of yokes and, and the other magnetic pole is located on the side toward the other yoke. | 12-04-2014 |