Title:
放電灯装置
Document Type and Number:
Japanese Patent JP4538998
Kind Code:
B2
Abstract:
A discharge lamp ballast circuit (100) has a snubber circuit to perform a soft switching when the MOS transistor (122) is turned off. The snubber circuit has, for example, a capacitor (126) that resonates with a reactance of the fly-back transformer (121) and enables a zero voltage switching. Before a breakdown of a discharge lamp (30), a control circuit (160) drives the MOS transistor (122) in a non-zero voltage switching manner by turning on the MOS transistor just after a peak voltage. The non-zero voltage switching increases an output voltage of the fly-back transformer. After the breakdown of the discharge lamp (30), the control circuit (160) turns on the MOS transistor in the zero voltage switching manner to perform the soft switching. As a result, it is possible to reduce switching loss during a lighting of the discharge lamp and to supply sufficient voltage in the lighting preparation period.
Inventors:
Koyama Sotoyama
Application Number:
JP2001249343A
Publication Date:
September 08, 2010
Filing Date:
August 20, 2001
Export Citation:
Assignee:
株式会社デンソー
International Classes:
H02M3/28; H05B41/24; H05B41/288; H05B41/282
Domestic Patent References:
| JP2000340385A | ||||
| JP2001218455A | ||||
| JP9260076A | ||||
| JP10144488A | ||||
| JP2000092832A | ||||
| JP6124790A | ||||
| JP2000133490A |
Attorney, Agent or Firm:
Kazuyuki Yahagi
Taihei Nonobe
Taihei Nonobe