| 摘要 |
PROBLEM TO BE SOLVED: To provide a technology of detecting current in a circuit of a battery powered portable electronic product or the like. SOLUTION: The current detecting circuit includes a current detecting resistor connected to an input of the current detecting circuit. The current detecting resistor receives a current to be detected from the input of the current detecting circuit. The current to be detected is converted to a current detecting voltage. A first PN junction diode is connected to the current detecting resistor. A light-emitting diode (LED) is connected to the first PN junction diode, and a current detection threshold value substantially proportional to a difference between a forward voltage drop of the LED and a forward voltage drop of the first PN junction diode is provided. The first PN junction diode is so connected that it is biased from the forward voltage drop of the LED. The LED is so connected to the current detecting resistor that it generates output when a current detecting voltage from the current detecting resistor reaches the current detection threshold value. COPYRIGHT: (C)2009,JPO&INPIT
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