Adjustable voice coil motor driver

An adjustable voice coil motor (VCM) driver for configuring a signal for controlling a VCM, said adjustable VCM driver comprising:

• a voltage accessor configured to access a voltage at an error amplifier of a VCM driver;
• a target value accessor configured to access a target value at said error amplifier;
• a difference value determiner configured to determine a difference value between said target value and said voltage;
• and
• a compensation value adjuster configured to adjust an impedance value of a variable compensation network based on said difference value, wherein said variable compensation network is coupled with said error amplifier, said compensation value adjuster comprising:
• a combination of a variable capacitor in series with a resistor, said resistor comprising a fixed resistor and a variable resistor positioned in a feedback path of said error amplifier, said combination being said variable compensation network, said variable compensation network being configured to be dynamically adjusted via opening and closing switches to establish an impedance to insert into said feedback path, said impedance determined according to a value programmed into a control register;
• a VCM driver operation mode adjuster configured to adjust said impedance value of said variable compensation network according to a mode of a VCM driver operation, said mode of said VCM driver operation comprising seeking or tracking, said VCM driver operation mode adjuster comprising:
• a bandwidth modifier configured for modifying a bandwidth according to said mode of a VCM driver operation, wherein said modifying is based on whether said VCM driver is seeking or tracking;
• and
• a VCM operating environment mode adjuster configured to adjust said impedance value of said variable compensation network according to a mode of a VCM operating environment, said VCM operating environment mode adjuster comprising:
• a temperature sensor reader configured for reading a temperature sensor and making corresponding adjustments to said variable compensation, said making corresponding adjustments comprising implementing a temperature compensation algorithm, said temperature compensation algorithm configured for enabling said variable compensation network to adapt to a change in temperature within said VCM.

A hard disk drive comprising:

• a housing;
• at least one disk mounted to the housing and rotatable relative to the housing;
• an actuator mounted to said housing and being movable relative to said at least one disk, said actuator having a suspension for reaching over said at least one disk, said suspension having a slider coupled therewith, said slider having a read/write head element;
• and
• a compensation value adjuster configured for adjusting an impedance value of said variable compensation network based on a difference value between a voltage accessed at an error amplifier of a voice coil motor (VCM) driver and a target value accessed at said error amplifier, wherein said compensation value adjuster is coupled with said error amplifier, said compensation value adjuster comprising:
• a combination of a variable capacitor in series with a resistor, said resistor comprising a fixed resistor and a variable resistor positioned in a feedback path of said error amplifier, said combination being a variable compensation network configured to be dynamically adjusted via opening and closing switches to establish an impedance to insert into said feedback path, said impedance determined according to a value programmed into a control register;
• a VCM driver operation mode adjuster configured to adjust said impedance value of said variable compensation network according to a mode of a VCM driver operation, said mode of said VCM driver operation comprising seeking or tracking, said VCM driver operation mode adjuster comprising:
• a bandwidth modifier configured for modifying a bandwidth according to said mode of a VCM driver operation, wherein said modifying is based on whether said VCM driver is seeking or tracking;
• and
• a VCM operating environment mode adjuster configured to adjust said impedance value of said variable compensation network according to a mode of a VCM operating environment, said VCM operating environment mode adjuster comprising:
• a temperature sensor reader configured for reading a temperature sensor and making corresponding adjustments to said variable compensation network, said making corresponding adjustments comprising implementing a temperature compensation algorithm, said temperature compensation algorithm configured for enabling said variable compensation network to adapt to a change in temperature within said VCM.