Method and apparatus for multirate sampling for disk drive spindle control

摘要

In the spindle control system of the present invention the compensator is divided into two portions. The first portion is driven by a first clock signal at a first frequency and a second portion is driven by a second clock signal at a second frequency derived from the first clock signal. In particular, the integrator utilizes a clock which increases the time measurement to be a longer interval than the measurement utilized for the remainder of the compensator circuit. This allows the absolute speed to be adjusted with a high resolution independent of the gain. Therefore, the gain can be maintained and the loop dynamics are preserved, maintaining dynamic range and stabilization while increasing the resolution of control of the spin speed.