PMAD/PSA digital feedback system
View Patent ↗A system and method for controlling operation of a motor system that addresses the design challenges for the small form factor optical disk system. The control system can be operable to obtain digital feedback from a spin motor. The present invention includes detecting data representing a position on an optical medium and determining a detection rate; comparing the detection rate to a reference rate to provide an error rate; generating an output command in response to the error rate to provide a drive output which commands a voltage applied to a spin motor to adjust the spin speed of said spin motor.
1. A method for obtaining digital feedback from a spin motor comprising:
detecting data representing a position on an optical medium and determining a detection rate;
comparing said detection rate to a reference rate to provide an error rate;
generating an output command in response to said error rate to provide a drive output which commands a voltage applied to a spin motor to adjust the spin speed of said spin motor.
2. The method of claim 1 , wherein detecting data comprises data including a plurality of PSAs or PMADs.
3. The method of claim 2 , wherein said PSAs or PMADs are equally spaced along a spiral extending across said optical medium.
4. The method of claim 1 , wherein said generating said output command comprises performing an integration routine using a variable proportional gain and integrator gain which correspond to said PSA or PMAD.
5. The method of claim 1 , wherein said reference rate comprises about 2 milliseconds.
6. The method of claim 1 , wherein said data is used to access a lookup table, said data being acquired from said lookup table including a proportional gain and an integrator gain.
7. A system for obtaining digital feedback from a spin motor comprising:
a control module operable to detect data representing a position on an optical medium and determine a detection rate, to compare said detection rate to a reference rate to provide an error rate, and to generate an output command in response to said error rate to provide a drive output which commands a voltage applied to a spin motor to adjust the spin speed of said spin motor.
8. The system of claim 7 , wherein said data comprises a plurality of PSAs or PMADs.
9. The system of claim 8 , wherein said PSAs or PMADs are equally spaced along a spiral extending across said optical medium.
10. The system of claim 7 , wherein said output command is generated from an integration routine using a variable proportional gain and variable integrator gain which correspond to said PSA or PMAD.
11. The system of claim 7 , wherein said reference rate comprises about 2 milliseconds.
12. The system of claim 7 , wherein said data is used to access a lookup table, said data being acquired from said lookup table including a proportional gain and an integrator gain.