Title:
駆動回路、車両用灯具
Document Type and Number:
Japanese Patent JP6634293
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide a vehicle lighting device, having a light-emitting part in which a plurality of semiconductor light-emitting elements are connected in series, capable of maintaining a light-emitting state of the light-emitting part against both of a drop in an input voltage from a battery and a rise in a forward voltage of the semiconductor light-emitting element while achieving cost reduction without need for having a step-up and -down function in a drive circuit.SOLUTION: The drive circuit, driving a light-emitting part of a vehicle lighting device having a serially connected circuit in which a plurality of semiconductor light-emitting elements are connected in series, includes: a driving voltage generation part generating a driving voltage for driving the semiconductor light-emitting elements on the basis of an input voltage from a battery; a bypass control part controlling a bypass switch connected in parallel to at least one of the semiconductor light-emitting elements on the basis of a difference between the input voltage and a forward voltage of the serially connected circuit.SELECTED DRAWING: Figure 1
Inventors:
Tomoyuki Ichikawa
Atsushi Ozawa
Atsushi Ozawa
Application Number:
JP2016003637A
Publication Date:
January 22, 2020
Filing Date:
January 12, 2016
Export Citation:
Assignee:
Koito Manufacturing Co., Ltd.
International Classes:
H01L33/00; B60Q1/00; H05B45/00
Domestic Patent References:
| JP2014050112A | ||||
| JP2015054555A | ||||
| JP2014060877A | ||||
| JP2014017463A | ||||
| JP2010016198A | ||||
| JP2009129564A | ||||
| JP2008282855A | ||||
| JP2011113684A | ||||
| JP2011233264A |
Foreign References:
| US20140203716 | ||||
| KR1020150143231A |
Attorney, Agent or Firm:
Masanobu Iwata
Hiroto Nakagawa
Atsuo Waki
Nobuo Suzuki
Hiroto Nakagawa
Atsuo Waki
Nobuo Suzuki