METHOD AND APPARATUS FOR COIN OR OBJECT SENSING USING ADAPTIVE OPERATING POINT CONTROL

摘要

A coin sensor is provided including a method and apparatus for providing adaptive operating point (AOP) control. The AOP control is provided using circuits and associated methods and algorithms connected between measurement circuits of the coin sensor and the coin sensor oscillator. The AOP control automatically monitors and controls the quiescent voltage levels of four signals used by the coin sensor to discriminate coins. The four signals represent coin size and coin composition. In addition, the AOP control automatically performs calibration and adjustment functions both during manufacture of the coin sensor system and during its operational life. The automatic monitoring and control functions provided by the AOP control result in a significant increase in the dynamic range of the coin sensor response. This reduces the coin false-reject rate while improving the coin discrimination precision.