Control of stepper motor in an optical disc
AssigneeLSI Logic Corporation
InventorAinobu Yoshimoto
Life of this patent
Estimating the term…
Abstract
A method for controlling a stepper motor in an optical disc system, comprising the steps of (A) measuring a static offset of a center error signal, (B) measuring a maximum value, minimum value and an average value of the center error signal in response to rotating the optical disc, (C) computing one or more upper threshold values and one or more lower threshold values of the center error signal, (D) sampling the center error signal, (E) comparing the center error signal to the one or more upper threshold values and to the one or more lower threshold values and (F) computing a control output to control the stepper motor in response to comparing the center error signal to the one or more upper and lower threshold values.
Claims17
A method for controlling a stepper motor in an optical disc system, comprising the steps of:
- (A) measuring a static offset level of a center error signal;
- (B) measuring a maximum value, minimum value and an average value of said center error signal in response to rotating said optical disc;
- (C) computing one or more upper threshold values and one or more lower threshold values of said center error signal;
- (D) sampling said center error signal;
- (E) comparing said center error signal to said one or more upper threshold values and to said one or more lower threshold values;
- and
- (F) computing a control output to control said stepper motor in response to comparing said center error signal to said one or more upper and lower threshold values.
An apparatus for controlling a stepper motor in an optical disc system comprising:
- means for measuring a static offset of a center error signal;
- means for measuring a maximum value, minimum value and an average value of said center error signal in response to rotating said optical disc;
- means for computing one or more upper threshold values and one or more lower threshold values of said center error signal;
- means for sampling said center error signal;
- means for comparing said center error signal to said one or more upper threshold values and to said one or more lower threshold values;
- and
- means for computing a control output to control said stepper motor in response to comparing said center error signal to said one or more upper and lower threshold values.
An apparatus comprising:
- a stepper motor configured to adjust a position of an optical housing in an optical disc system in response to a drive signal;
- a stepper motor driver configured to (i) generate said drive signal and (ii) drive said stepper motor in response to a control signal;
- a control circuit configured to generate said control signal in response to a plurality of photo-diode signals;
- and
- a photo-diode distribution portion configured to generate said photo-diode signals.
Dependencies are inferred from the claim text.