Abstract:
A design protection circuit for a logic circuit comprised of a counter for receiving clock pulses with the logic circuit and apparatus for resetting the logic circuit upon the counter counting a predetermined number of clock pulses, the predetermined number being higher than a highest number of clock pulses required by the logic circuit for carrying out a simulated logical function.
Abstract:
For use in a transmission system in which an input data stream is transmitted in plural data streams each at a fraction of the input data stream rate and plural clock stream pairs each at the fraction of the input data clock rate, a receiver, comprised of apparatus for receiving the plural data streams, apparatus for determining frame timing differences between frame signals contained in each of the received plural data streams, apparatus for varying the timing of one received data stream relates to another, whereby their relative timing is adjusted, apparatus for combining the timing adjusted plural data streams into an output data stream having a similar data stream rate as the input data stream, apparatus for recovering a clock from one of the plural data streams, and for generating an output clock signal therefrom at the input data clock rate, and apparatus for aligning the output data stream with the output clock signal, whereby an output data stream and an output clock signal are provided having similar data rates as the input data stream and clock rates.
Abstract:
According to the invention there is provided a method of signal coding that permits high speed data transmission over multiple pairs of UTP-5 cable from a transmission end to a receiving end which includes, at the transmission end, separating an incoming frame of data into a plurality of byte streams with a predefined sequence of bytes assigned to each of the streams, encoding every 2 bits of data in each stream into one of 4 logical voltage levels forming a symbol or quat thereby reducing the symbol or baud rate by 50% and inserting an escape sequence into one or more of the streams consisting of a sequence of zero's followed by a control code to indicate a transition from one state to another. At a receiving end, the method further includes reading the escape sequence and decoding the signals in accordance with the code contained in the escape sequence.
Abstract:
A method and apparatus for building a packet grooming and aggregation engine is disclosed. The grooming and aggregation engine can be applied to the network for providing flexible aggregation and service multiplexing functions. A method and apparatus achieves the intended function that is easy to implement and easy for the network operator to manage, yet provides enough flexibility to mix and match various services at the edge node of the network. One specific embodiment of the patent is an Ethernet over SONET mapping system where user traffic is aggregated and groomed into SONET transport virtual concatenation channels.
Abstract:
Gridded I/O pads for flip-chip packages in which a coaxial-like solder bump pad configuration is used in which the I/O pads closest to the signal or bump pad are power or ground pads. The ground pads surrounding the signal pad form a coaxial-like pad configuration for impedance matching at the transition from die to package substrate. The ground pads surrounding the signal pad may be connected by a metal trace to form a ground pad ring. The invention employs conductor-backed ground coplanar waveguides (GCPW), which match impedance at connections between I/O cells and signal pads to enhance signal transmission, avoid reflection and leakage, and provide superior electromagnetic shielding. The present invention also supports high quantities of I/Os for a given die size, and supports flexible power and ground placement.
Abstract:
A user network interface device for interfacing between synchronous optical network (SONET)/synchronous digital hierarchy (SDH) which is characterized by a continuous stream of frames of data and an asynchronous transfer mode (ATM) characterized by a non-continuous stream of cells of data. The user network interface device includes an integral phase lock loop circuit to recover clock and data from an encoded incoming stream of data. In another embodiment, the network interface device synthesizes a high speed transmit clock from a low frequency reference source.
Abstract:
A method of interfacing between a non-continuous stream of cells of data and a continuous stream of frames of data, which includes transforming an incoming non-continuous cell stream into a continuous transmitted stream by inserting idle or non-assigned cells into the data stream during idle periods. The cells in the continuous stream are then mapped sequentially and contiguously onto the payload portions of frames. The frames are then transmitted synchronously.