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Patent Searching and Data


Title:
DEVICE FOR DRIVING LIGHT EMITTING ELEMENT
Document Type and Number:
Japanese Patent JP2010056305
Kind Code:
A
Abstract:

To supply a stable power voltage in controlling the duty of a light emitting element.

A device for driving the light emitting element includes: N pieces of light emitting element groups (N is an integer 1); a power circuit; N pieces of current drive circuits; a main feedback circuit; and an auxiliary feedback circuit. Each of the N pieces of light emitting element groups includes one or more light emitting elements. The power circuit includes a control input end, and supplies a power voltage to the N pieces of light emitting element groups. The N pieces of current drive circuits respectively include feedback output ends, generate N pieces of trains of drive currents respectively driving the N pieces of light emitting element groups based on the power voltage, and respectively generate main feedback voltages to the feedback output ends. The main feedback circuit imparts a main feedback signal to the control input end based on the N pieces of trains of main feedback voltages. The auxiliary feedback circuit imparts an auxiliary feedback signal to the control input end based on the power voltage. The power circuit adjusts the power voltage based on at least either the main feedback signal or the auxiliary feedback signal.


Inventors:
KATAOKA SHINICHIRO
UEDA RYUJI
TAKADA TAKESHI
ITO DAISUKE
YAMAMOTO YASUNAGA
KAWAHARA TSUKASA
Application Number:
JP2008219869A
Publication Date:
March 11, 2010
Filing Date:
August 28, 2008
Export Citation:
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Assignee:
PANASONIC CORP
International Classes:
H01L33/00; H02M3/155; H05B37/02
Attorney, Agent or Firm:
Takuji Yamada
Mitsuo Tanaka
Mitsuo Wada