Optical disk rotation speed control device and method

Abstract

The invention provides a kind of control method for optical rotate speed, includes following steps: generates the first control signal under the first control mode, generates the second control signal under the second control mode; under the first control mode, according to the first pulse of the first control voltage value and the second pulse with the second control voltage value, makes motor generates the first and the second armature current when it receives the first and the second pulse; under the second mode, generates the third control voltage value direct current signal according to the second control signal, makes motor generate the third armature current when it receives the direct current; examines the first, the second and the third armature current and outputs correspondent voltage value; calculates the motor coefficient by using the first, the second value and the first, the second measuring value; calculates the relative value of speed, and controls the motor speed according to the relative value.

Description

technical field [0001] The present invention relates to a disc rotation speed control device and method, in particular to a control device and method for obtaining the spindle motor rotation speed by detecting the armature current of the spindle motor. Background technique [0002] In the optical disc reading or recording system, two types of spindle motors are mainly used, one is a three-phase motor, and the three-phase motor is generally equipped with a Hall sensor (Hall sensor), which can detect the signal relative to the rotation frequency ( FG signal), so constant angular velocity (CAV) can be performed, and the current rotational speed can be known from the generated FG signal. In addition, because the three-phase motor can have a relatively high speed, it is mainly used in high-speed CD-ROM, CD-RW or DVD-ROM. However, the main disadvantage of the three-phase motor is that it is expensive, and the corresponding motor driver (motor diver) is also expensive. Therefore,...

AI Technical Summary

Problems solved by technology

This control method can stably stop the motor that drives the platter under normal circumstances, but in some unexpected situations, the motor will exit the platter before it stops or has been reversed, causing scratches on the platter surface

These accidents include (1) wrong estimation of the initial speed of the motor, which may be caused by severe scratches on the disc, and the time information cannot be read; the speed is not stable, and the stop action is performed, such as long-distance tracking.

(2) The weight driven by the spindle motor is inconsistent, such as the difference between an 8cm disc and a 12cm disc, or the inertia difference caused by some disc substrates being thicker or thinner than the specification

(3) The characteristics of the spindle motor are different, the same control current may have different deceleration torque

Images