发明名称 |
PWM controller with automatic low battery power reduction circuit and lighting device incorporating the controller |
摘要 |
A controller for controlling a voltage applied to a load from a power source includes a square wave producing circuit for connection in the circuit with the battery and the lamp. The square wave producing circuit produces a variable duty cycle square wave for controlling application of power to the load in accordance with the duty cycle of the square wave. The square wave producing circuit has a control input for varying the duty cycle of the square wave in response to a voltage at the control input. A voltage varying circuit is connected to the power source for producing a selectively variable voltage that is fed to the control input of the square wave producing circuit for selectively adjusting the duty cycle of the square wave. A low voltage detection circuit is connected to the power source and coupled to the control input of the square wave producing circuit for automatically producing a voltage that decreases the duty cycle of the square wave when the battery voltage decreases to or below a predetermined level.
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申请公布号 |
US6870329(B2) |
申请公布日期 |
2005.03.22 |
申请号 |
US20030345154 |
申请日期 |
2003.01.16 |
申请人 |
VECTOR PRODUCTS, INC. |
发明人 |
KRIEGER MICHAEL;RANDOLPH BRUCE;SHUM HENRY |
分类号 |
H05B39/04;H05B41/285;(IPC1-7):G05F1/00 |
主分类号 |
H05B39/04 |
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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