Cirrus Logic Inc.

Broadcom Corporation

Storage Technology Corporation

James M Graba

German S O Feyh

Louis Supino

Ba-Zhong Shen

William G Bliss

Mehmet Vakif Tazebay

Peiqing Wang

Ahmad Chini

Chung Ming Tu

Yencheng Chen

Michael J O'Keeffe

Hao Huang

Manav

Chung-Kal Chow

George I Noyes

A communication technique for energy efficient Ethernet (EEE) employs a systematic block forward error correcting code (FEC). The technique aligns a low power idle (LPI) refresh signal with the FEC frame. The refresh signal includes a known reference sequence, FEC systematic symbols, and FEC parity symbols. The technique may apply shortened FEC encoding and decoding on the partial data symbols and the parity symbols.

Robust low rate data channel in LPI mode for energy-efficient ethernet applications

A network interface includes a physical layer device coupled to a network link. A media access control module communicates with a link partner over the network link. An energy controller monitors a link utilization level of the network link and transitions, in response to the monitoring, the media access control module and the physical layer device to a low power idle mode, wherein the low power idle mode includes periodic transmission of a plurality of refresh frames in a refresh cycle and wherein at least one of the plurality of refresh frames is modified to include at least one first data payload.

Network interface with low power data transfer and methods for use therewith

Servo circuitry for counting tracks on an optical storage medium is disclosed. The servo circuitry is comprised of a differential phase detector and a digital phase-locked loop. The differential phase detector receives four signals from a quad-photodetector and correlates the four signals into a first correlation signal and a second correlation signal. The digital phase-locked loop receives an adjustable amplification value along with the positive correlation signal and the negative correlation signal. The digital phase-locked loop generates a track count signal based on the adjustable amplification value, the positive correlation signal, and the negative correlation signal. The track count signal represents track crossings on the optical storage medium. The digital phase-locked loop advantageously has an adjustable bandwidth based on the amplification value. The servo circuitry count tracks on both CDs and DVDs.

Servo circuitry for counting tracks on an optical storage medium

Servo circuitry for correlating signals using a correlation data structure is disclosed. The servo circuitry is comprised of a setup system coupled to a correlation system that contains the correlation data structure. The setup system receives four signals and converts the signals to digital values. The correlation system takes the digital values and enters them into the correlation data structure. The correlation data structure yields a correlation value based on the digital values. The servo circuitry advantageously yields the correlation value that is a function of all four signals using the correlation data structure.

Servo detection using a correlation data structure for concurrent processing of quad signals

An optical disk system comprises an optical disk device and control circuitry. The optical disk device stores user data and transfers an analog signal representing the user data to the control circuitry. The control circuitry sub-samples the analog signal to generate a sub-sampled signal. The control circuitry up-samples and re-times the sub-sampled signal using a control signal to generate an up-sampled and re-timed signal. A digital feedback loop in the control circuitry generates the control signal.

Re-timing and up-sampling a sub-sampled user data signal from in an optical disk

A track count estimator is provided for an optical storage device operating in either a CD-ROM mode or a DVD mode during a track seek. The track count estimator includes a state estimator to determine current and predicted estimates of the position and velocity of an optical pickup in the optical storage device according to the following equations:

Track count estimator for optical storage drives

A system and method for generating a unique sync pattern that may be appended to a selected data sector of a disk storage system. The data to be stored in the disk storage system is encoded in accordance with a desired fixed rate run-length limited code, such as a 2,7 code. The unique sync pattern is generated by first encoding a prescribed data word in accordance with the desired code. At least one bit of the encoded prescribed data word is then changed in a manner such that the changed encoded word still complies with the coding rules of the desired code, yet the resulting bit pattern does not represent any valid sequence of data in accordance with the desired code. Hence, the changed encoded word may be readily distinguished from data, thereby providing the synchronization function, while still being handled and processed by the same encoding/decoding circuitry as is employed to handle and process the data.

Growing community of inventors

Longmont, CO, United States of America

James M Graba