Patent ID: 6566838
Filing Date: 2003-05-20
Classification: G11B

Abstract:
A device for driving and controlling a rotation motor and a voice coil motor for a disk drive, the device comprising:a digital signal processor (DSP) functioning in a time sharing mode for carrying a plurality of functions; a bank of input/output registers connected to said DSP; a rotation motor circuit for controlling and driving the rotation motor for rotating a disk of the disk drive; a voice coil motor output stage for driving the voice coil motor for positioning a swinging arm of the disk drive with respect to the disk, said voice coil motor output stage being controlled in a switched mode based upon two control phases having a variable duty-cycle; a duty-cycle control loop comprising a current sensing circuit connected to the voice coil motor; an arm position control loop comprising a speed detection circuit connected to the voice coil motor; said duty-cycle control loop and said arm position control loop being digitally implemented by said DSP as a function of digital data representing a first analog signal generated by said current sensing circuit representative of current conducting in a winding of the voice coil motor, and a second analog signal generated by said speed detection circuit representative of a speed of the voice coil motor; a multiplexer for selecting among the first and second analog signals and a third analog signal representative of a drive current of the rotation motor; and an analog/digital converter functionally coupled in cascade to an output of said multiplexer for providing the digital data to respective registers of said bank of input/output registers.