Storage device such as hard disc reduces gain when reading data to e.g. half value of gain when writing data to reduce vibration

摘要

The device includes a magnetic disc with a servo zone having two servo pattern lines for each track. A servo demodulator detects the position of a head on the disc according to the servo pattern. A comparator outputs the difference between a target position signal and the detected position signal, and the resultant position error signal is amplified using a gain that is less than the gain used when reading data. A controller outputs a voice-coil motor operation rate signal to move the head according to the amplified position error signal. A method of detecting the position of a head on a disc is also claimed.