发明名称 |
Photosensor circuits including a switch mode power converter, a driver transistor and a relay coil |
摘要 |
Photosensor circuits include a relay coil configured to control application of an alternating current (AC) power source to a load. The circuit includes a pulse width modulator circuit configured to generate a pulse width modulated signal having a pulse width that varies responsive to an average voltage across the relay coil. A photo control circuit is configured to control application of the pulse width modulated signal to a drive transistor responsive to a detected light level. A power circuit includes a rectifier circuit and a voltage divider circuit configured to generate a regulated power signal. A outputs a current responsive to a level of light detected by the phototransistor. A low pass filter circuit is coupled to a first terminal of the phototransistor filters the output current of the phototransistor to provide a light level signal voltage and a select transistor couples the pulse width modulated signal to the drive transistor responsive to the light level signal voltage having a selected level.
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申请公布号 |
US8026470(B2) |
申请公布日期 |
2011.09.27 |
申请号 |
US20080255881 |
申请日期 |
2008.10.22 |
申请人 |
TYCO ELECTRONICS CORPORATION |
发明人 |
FLAHERTY RICHARD CHARLES |
分类号 |
H01J40/14 |
主分类号 |
H01J40/14 |
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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