发明名称 |
Method and apparatus for controlling minimum brightness of a fluorescent lamp |
摘要 |
An efficient power conversion circuit for driving a fluorescent lamp uses a minimum pulse generator circuit to control the minimum on-time of a time modulated signal to increase the dimming range of the fluorescent lamp operating over a wide range of temperature and supply voltage. A minimum number of lamp current cycles with respective amplitudes above a preset threshold is typically required to avoid flickering or shimmering during minimum brightness. The minimum pulse generator circuit counts the lamp current cycles and adjusts the on-time accordingly to guarantee the minimum number of cycles with respective amplitudes above a preset threshold under all operating conditions.
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申请公布号 |
US6654268(B2) |
申请公布日期 |
2003.11.25 |
申请号 |
US20020234653 |
申请日期 |
2002.09.03 |
申请人 |
MICROSEMI CORPORATION |
发明人 |
CHOI HWANGSOO |
分类号 |
H02M7/5383;H02M7/53846;H02M7/53862;H05B41/282;H05B41/392;(IPC1-7):H02M7/538 |
主分类号 |
H02M7/5383 |
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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