发明名称 |
Device for accurately detecting end of usage lifetime of a discharge lamp |
摘要 |
When a discharge lamp repeatedly flickers out after illuminating for a long period of time because the same discharge lamp is nearing the end of its usage lifetime, a stored voltage of a capacitor rises gradually every time the discharge lamp flickers out. When the stored voltage of the same capacitor becomes no less than a predetermined voltage, a comparator generates a high level voltage which actuates a transistor. The transistor then terminates the operations of a PWM circuit to deactuate the discharge lamp.
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申请公布号 |
US5880563(A) |
申请公布日期 |
1999.03.09 |
申请号 |
US19970811210 |
申请日期 |
1997.03.05 |
申请人 |
DENSO CORPORATION |
发明人 |
TOYAMA, KOICHI;KATO, KOICHI;AIDA, KENJI |
分类号 |
H05B41/282;H05B37/03;H05B41/292;(IPC1-7):H05B37/02 |
主分类号 |
H05B41/282 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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