发明名称 |
Laser power supply circuit as well as option recording and/or reading device comprising such a laser power supply circuit |
摘要 |
A laser power supply control circuit may, when the power supply is initially turned on, temporarily permit an excessive supply voltage which may damage the laser. To prevent that, but without restricting the operating range or speed of response of the control circuit, the invention provides a sensing circuit for deriving a sensor signal indicative of a change in the loop gain of the control circuit when it departs from its normal operating mode. The sensor signal is used to prevent the power supply control signal from increasing excessively after a temporary reduction in supply voltage, but permits the control signal to operate substantially immediately when the supply voltage returns to its normal operating range.
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申请公布号 |
US5708647(A) |
申请公布日期 |
1998.01.13 |
申请号 |
US19950576624 |
申请日期 |
1995.12.21 |
申请人 |
U.S. PHILIPS CORPORATION |
发明人 |
BIERHOFF, MARTINUS P. M.;VAN MIL, JOB F. P. |
分类号 |
G11B7/135;G11B7/125;G11B7/126;H01S3/10;H01S3/13;H01S5/042;H01S5/068;H01S5/0683;(IPC1-7):G11B7/00 |
主分类号 |
G11B7/135 |
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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