| 摘要 |
A method and apparatus are provided for selectively de-tuning a resonant circuit (410, 420) of a remotely powered device (400). The resonant circuit is tuned to a carrier frequency corresponding to an interrogation signal from an interrogator which powers the remotely powered device. Selective de-tuning of the resonant circuit may become necessary when the interrogation signal from the interrogator device is too powerful for the monitoring device resulting in an induced voltage that exceeds a predetermined threshold. When operative, selective de-tuning reduces the efficiency of coupling power from the interrogation signal into the monitoring device. As a result, less power is coupled into the device, which reduces unwanted heating, limits voltage applied to the power terminal of the device to a safe, desirable level, prevents damage to the device and allows it to operate effectively in temperature sensing applications.
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