Abstract:
An exemplary signal processing apparatus includes a signal transmission port, a first signal processing circuit, a second signal processing circuit, and a control circuit. The signal transmission port is shared between a first signal processing operation and a second signal processing operation. The first signal processing circuit performs the first signal processing operation, wherein when the signal processing apparatus operates, the first signal processing circuit is not required to be consistently enabled to use the signal transmission port for signal transmission. The second signal processing circuit performs the second signal processing operation, wherein the signal transmission port is not always required to carry out signal transmission each time the second signal processing circuit is enabled to perform the second signal processing operation. The control circuit selectively enables the first signal processing circuit or the second signal processing circuit.
Abstract:
A optical disk drive long distance seek control device and method thereof, capable of feeding back the optical head control device through the step motor control device during the long distance seek; wherein, the step motor control device comprises a velocity profile generator capable of producing a quadratic profile to stabilize the step motor when finishing the seek; and more particular, the optical head control device uses a center error signal and a velocity error signal alternatively; moreover, the velocity error signal can be adjusted according to the output signals from the optical head control device and the step motor control device through a weighting mechanism.
Abstract:
The present invention relates to an optical medium judging method for avoiding the collision of an objective lens with a disk or the failure to judge a warped disk when the optical disk drive judging the disk. This method will move the objective lens so as to obtain the data of the laser beam reflection amount of the focusing beam on the plastic layer of the optical disk. By using the reflection amount, the driving circuit will output a rising direct current voltage of a voltage difference to drive an actuator so as to move the objective lens to a proper position capable of judging the disk without colliding with the disk.
Abstract:
An optical disc drive includes a pickup head for receiving a reflective light from an optical disc and detecting a reflection signal accordingly, a derived signal generator for generating a derived signal derived from the reflection signal, an envelop generator for filtering the derived signal to generate an envelop of the derived signal, and a controller for receiving the envelop of the derived signal, comparing the envelop of the derived signal with a threshold, and controlling the optical disc drive entering a protection mechanism, when the envelop crosses the threshold in a predetermined time.
Abstract:
A CD drive has a pick-up head for reading data of an optical disc, and a motor for rotating the optical disc. The method first adjusts the rotary speed of the motor so that the vibration frequency of the CD drive is approximately the resonance frequency of a coil of the pick-up head. Then, when the vibration frequency of the CD drive is approximately the resonance frequency of the coil of the pick-up head, the method detects if the voltage of a central error (CE) signal of the CD drive is greater than a threshold voltage. Finally, the method determines if the optical disc is an unbalanced disc according to the comparison result.
Abstract:
A optical disk drive long distance seek control device and method thereof, capable of feeding back the optical head control device through the step motor control device during the long distance seek; wherein, the step motor control device comprises a velocity profile generator capable of producing a quadratic profile to stabilize the step motor when finishing the seek; and more particular, the optical head control device uses a center error signal and a velocity error signal alternatively; moreover, the velocity error signal can be adjusted according to the output signals from the optical head control device and the step motor control device through a weighting mechanism.
Abstract:
An apparatus for controlling half-wave layer jumping of a pickup head of an optical disk drive includes a half-wave layer jump controller and an output logic unit. The controller receives a focus error signal from a preamplifier to generate a control signal according to the half wave of the focus error signal. The output logic unit outputs a kickout signal, a half-wave layer jump control compensation, and a brake signal in accordance with the timing of the half-wave layer jump control. The output signal are added to a gap balance signal, and the sum is used for controlling layer jumping of the pickup head. Such method adopts an error obtained by comparing the focus error signal with an ideal cycle signal as an additional compensational force for layer jumping.
Abstract:
A seeking control system in an optical disc drive is disclosed. The system comprises a servo controller, a velocity control unit, and a switch unit. The servo controller receives a central servo signal to output a first tracking control signal for the tracking coil. The velocity control unit receives a tracking error signal to determine a velocity of the pickup head and compares the velocity of the pickup head with a predetermined velocity profile to generate the second tracking control signal. The switch unit outputs the second tracking control signal instead of the first tracking control signal to the motor driver to control the pickup head moving steadily.
Abstract:
The present invention relates to an optical medium judging method for avoiding the collision of an objective lens with a disk or the failure to judge a warped disk when the optical disk drive judging the disk. This method will move the objective lens so as to obtain the data of the laser beam reflection amount of the focusing beam on the plastic layer of the optical disk. By using the reflection amount, the driving circuit will output a rising direct current voltage of a voltage difference to drive an actuator so as to move the objective lens to a proper position capable of judging the disk without colliding with the disk.