Pulse generator and disk sector boundary signal generator with wow and flutter compensation

摘要

A pulse generator and a disk sector boundary signal generator are implemented using an optical pattern of alternating light and dark radial lines or segments which are adhered to and rotate in unison with the rotor of a motor and are sensed by an optical sensor. The output of the optical sensor includes error conditions including sensor error, pattern error component, the wow component of the motor and the flutter component of the motor. A first pulse generating means eliminates sensor and pattern error components and the flutter component leaving only the wow component of the sensor output. A second pulse generating means that eliminates the higher frequency error components leaving pattern error components, wow components and flutter components, where the system is designed to generate flutter components with a frequency at least ten times the frequency of the wow component. The first pulses serve as disk sector boundary reference pulses. The second pulses, at a higher frequency, between first pulses contain pattern error pulses corresponding to the sector and the final pulse serves as a sector boundary pulse.