A method for driving a motor by imposing the current in the motor by means of power current mirrors is presented. This allows driving the motor in current with higher accuracy and lower electrical noise. The Hard Disk Drive application is an example where higher resolution is required for the VCM motor. Furthermore this method reduces the complexity of the system eliminating components and high performance circuits. Moreover this approach reduces the development and manufacturing cost by simplifying the testability and the analysis of the system. The intrinsic elimination of DC offset also takes out the need for the system offset calibration phase and significantly improves on the harmonic distortion of the transfer function. Furthermore this method offers the advantage of faster overall response of the system and higher efficiency. The additional benefit of this method is the ability to have a motor drive system that can be easily and smoothly switched between a PWM drive and a linear drive for different modes of operation of the motor itself.

 
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> Method and apparatus for reducing off-track writes in data storage devices

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