摘要 |
<p>An coin sensor utilizes time-multiplexing of LC oscillators having natural frequencies F1A, F1B, F2, and F3 to produce magnetic fields in three sets of windings. As a coin passes through the coin sensor, the LC oscillators are separately enabled in a sequence to produce a frequency profile for each set of windings. A first winding produces a frequency profile for a cross-sectional area of a coin, and a third winding produces a frequency profile for further distinguishing the relative size of a coin. A microcontroller identifies signatures points from the frequency profiles and compares the signature points with stored signatures for a multitude of coins and/or tokens.</p> |