Gear detection circuit and wrist watch

Abstract

A gear position detection device for detecting a gear having multiple fingers is provided. The detection device includes a substrate, a control chip, and a drive line, a sense line, a first drive electrode, a second drive electrode, a first sense electrode and a second sense electrode formed on the substrate. The first and second drive electrodes are connected to the drive line to receive a drive signal. The first and second sense electrodes form induced electric field respectively with the first and second drive electrodes, and respectively output a first detected signal and a second detected signal via the sense line. The control chip outputs the drive signal via the drive line, receives the first and second detected signals via the sense line, calculate a differential signal between the first and second detected signals, and count a number of high levels of the differential signal to count a finger number.

Dependencies are inferred from the claim text.