Silicon Image Gmbh

Bruce Kim

Gyudong Kim

Seung Ho Hwang

Hoon Choi

Min-Kyu Kim

Ook Kim

Russel A Martin

David D Lee

Daeyun Shim

Victor M Da Costa

Eric A Lee

A data sampling circuit that employs an oversampling clock to oversample a data signal, a phase tracking circuit for use in such a sampling circuit, and a receiver and system including such a sampling circuit. Preferably, phase tracking is implemented by systematically identifying and rejecting at least one worst sampling position, and sampling the data signal at a non-rejected sampling position. Preferably, phase tracking is accomplished by counting through-transitions of edges of the sampled data signal through each oversampling position, and rejecting an oversampling position having a highest count of through-transitions. In some embodiments, different phase tracking methods (at least one of which includes the step of generating through-transition counts) are used for different types of input data. Other aspects of the invention are methods for determining an oversampling position for oversampling a data signal, and methods for oversampling a data signal including by generating through-transition counts.

Data sampling method and apparatus using through-transition counts to reject worst sampling position

A data sampling method and circuit employing an oversampling clock to oversample a data signal, a phase tracker for use with or in a data sampling circuit, and a method for identifying a sequence of best sampling positions for sampling a data signal from signal samples generated using an oversampling clock. In some embodiments, data indicative of the phase of at least one of the oversampling clock's sampling positions relative to the center of the data eye are low-pass filtered in a manner determined by the data signal's bit rate. In other embodiments, the number of dead cycles of the phase tracker decision loop is reduced by generating possible solutions in parallel and moving the feedback point so as to occur as late as practical, or the phase tracker ignores a sample set when updating its determination of the best sampling position when the sample set indicates that the data signal has less than a predetermined number of transitions during a corresponding tracking period.

Reduced dead-cycle, adaptive phase tracking method and apparatus

A method of transmitting data in a system including at least one data channel and a separate clock channel is disclosed. The method involves combining a clock signal to be transmitted on the clock channel with a data signal to generate a combined clock and data signal. In one embodiment, the data signal has been generated from data words using an encoding scheme that shifts an energy spectrum of the data signal away from an energy spectrum of the clock signal. In another embodiment, the clock signal has a plurality of pulses each having a front edge and a back edge, and the data signal is modulated onto the clock signal by moving at least one edge (i.e. front or back or both) of the plurality of pulses, thereby to create a combined clock and data signal.

Combining a clock signal and a data signal

A scheme for reducing jitter in high-speed digital communication by adaptively controlling the loop bandwidth of a receiver PLL to reduce the relative jitter between the recovered data and clock. The scheme uses phase pointer activity to represent the relative jitter. The phase pointer activity is measured and used to control the receiver PLL loop bandwidth. The receiver PLL loop bandwidth is repeatedly incremented or decremented by a step size based on the comparison between a newly measured activity value and the old activity value, until the phase pointer activity reaches a minimum. Because the PLL performance requirement of the transmitter can be relaxed, compatibility with legacy transmitters and multi-vendor transmitters is enhanced. Because tight control of fabrication process parameters of PLLs may be relaxed, the fabrication yield may also be improved.

Method and apparatus for adaptive control of PLL loop bandwidth

The present invention is directed to systems and methods for protecting digital content during transmission. One version of the invention provides a method for encryption in a high-speed digital video transmission system that includes the steps of: a) performing transition controlled encoding of a first sequence of n bit data words into encoded n+1 bit data characters where the n is a positive integer, b) performing XOR masking of the encoded n+1 bit data characters with an XOR mask to produce masked n+1 bit data characters; c) DC balancing the masked n+1 bit data characters to produce DC balanced, masked n+2 bit data characters; d) scrambling the DC balanced, masked n+2 bit data characters using a scrambling formula to produce encrypted n+2 bit data characters; e) encoding control data into encoded n+2 bit control characters, f) generating a serial data stream in response to the encrypted data characters and encoded control characters, and g) transmitting the serial data stream over a communication link. Subsequent to step (e) and prior to step (f), the method can further include the step of encrypting the encoded n+2 bit control characters, such that the generating step generates a serial data stream in response to the encrypted data characters and the encrypted control characters.

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Los Altos, CA, United States of America

Bruce Kim