发明名称 |
Differential current sensor device and method |
摘要 |
A current sensor having a pair of sense transistors is disclosed. The sense transistors sense a current conducted by a power transistor of a voltage regulator. The ratio in size between the power transistor and the sense transistors corresponds to a scaling factor M. Each sense transistor has an associated series connected sense resistor. The two sense resistors are unbalanced and provide a differential voltage based on the sensed current at the sense transistor to a transconductor. The transconductor has heavy emitter degeneration to provide an output current substantially proportional to the current conducted by the primary power transistor, the proportion determined by the scaling factor M and a ratio of the emitter degeneration and sense resistors.
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申请公布号 |
US7994766(B2) |
申请公布日期 |
2011.08.09 |
申请号 |
US20080130164 |
申请日期 |
2008.05.30 |
申请人 |
FREESCALE SEMICONDUCTOR, INC. |
发明人 |
DE LIMA FILHO JADER ALVES;PIMENTA WALLACE A. |
分类号 |
G05F1/573;G05F1/575 |
主分类号 |
G05F1/573 |
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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