Abstract: In an integrated decision feedback equalizer and clock and data recovery circuit one or more flip-flops and/or latches may be shared. One or more flip-flops and/or latches may be used in retiming operations in a decision feedback equalizer and in phase detection operations in a clock recovery circuit. Outputs of the flip-flops and/or latches may be used to generate feedback signals for the decision feedback equalizer. The output of a flip-flop and/or latches may be used to generate signals that drive a charge pump in the clock recovery circuit.

Abstract: Systems and methods for optimizing operation of a transceiver device are disclosed. The method may include parallel processing an input signal through a first path having a first frequency response and a second path having a second frequency response. The second frequency response may be higher than the first frequency response. Signals from the first and second paths may be combined, creating an output signal having a desired gain and frequency. The parallel processing may adjust a gain of at least one of the first path and the second path. The parallel processing may equalize at least one of the first frequency response and the second frequency response. The input signal may be from a 10 GBit Ethernet channel and/or a Fibre channel.

Abstract: Aspects of the invention may provide a method and system for adjusting a gain and/or a frequency response of an input signal for a multimode PHY device. A signal divider (704) may apportion the input signal into a gain adjustment signal and/or an equalization adjustment signal upon receipt of the input signal. A signal adjuster (702) coupled to the signal divider (704) may adjust a gain of the apportioned gain adjustment signal within the multimode PHY device (130). An equalizer (706) coupled to the signal divider (704) may be configured to equalize the equalization adjustment signal within the multimode PHY device (130). A summer (708) coupled to the equalizer (706) and signal adjuster (702) may be adapted to sum the adjusted adjustment signal and the equalized equalization adjustment signal within the multimode PHY device (130) to create an output equalized signal (712) having a desired gain and/or frequency response.

Abstract: A built-in self test for receiver operation is provided through a testing method that evaluates characteristics of a received signal eye diagram. The receiver receives a serial data signal and applies compensation to that received serial data signal to generate a compensated serial data signal. The properties of an eye diagram associated with the compensated serial data signal are measured. In this context, certain desired eye diagram properties are characterized by parameters indicative of pass/fail criteria for receiver testing. The measured eye diagram properties are then compared against the parameters. A receiver testing conclusion signal is then output based on results of the comparison.

Abstract: Various example embodiments are disclosed. According to an example embodiment, an apparatus may include a continuous time filter, a decision feedback equalizer, a clock and data recovery circuit, and an adaptation circuit. The adaptation circuit may be configured to adapt equalization according to at least one dithering algorithm by adjusting a delay adjust signal based on a mean square error of equalized data signals.

Abstract: A high-speed bit stream interface module interfaces a high-speed communication media to a communication Application Specific Integrated Circuit (ASIC) via a Printed Circuit Board (PCB). The high-speed bit stream interface includes a line side interface, a board side interface, and a signal conditioning circuit. The signal conditioning circuit services each of an RX path and a TX path and includes a limiting amplifier and a clock and data recovery circuit. The signal conditioning circuit includes an AGC loop, an equalizer, and an equalizer feedback loop. The AGC loop includes a gain path and a feedback path that couples to the output of the equalizer. The equalizer feedback loop couples to the output of the equalizer and produces spectral shaping control settings that the equalizer uses to produce an equalized high-speed serial bit stream at an equalizer output.

Abstract: A first device transmits data over a first branch of a communications link toward a second device. That second device loops the received data pattern back over a second branch of the communications link. A bit error rate of the looped back data pattern is determined and a pre-emphasis applied to the transmitted data pattern is adjusted in response thereto. The first device further perturbs the data pattern communications signal so as to increase the bit error rate. The pre-emphasis is adjusted so as to reduce the determined bit error rate in the looped back data pattern in the presence of the perturbation. The steps for perturbing the signal and adjusting the pre-emphasis are iteratively performed, with the perturbation of the signal increasing with each iteration and adjustment of the pre-emphasis being refined with each iteration. The signal is perturbing by injecting modulation jitter into the signal (increasing each iteration) and adjusting amplitude of the signal (decreasing each iteration).

Abstract: Equalization is provided in a high speed communication receiver that includes in various aspects an automatic gain control input stage, a decision feedback equalizer, a clock and data recovery circuit and equalization control circuits. The automatic gain control stage may include a continuous time filter with an adjustable bandwidth. A threshold adjust signal may be applied to the output of the automatic gain control stage. The equalization control circuits may be implemented in the digital domain and operate at a lower clock speed than the data path.

Abstract: A high-speed bit stream interface module interfaces a high-speed communication media to a communication Application Specific Integrated Circuit (ASIC) via a Printed Circuit Board (PCB). The high-speed bit stream interface module includes a line side interface, a board side interface, and a signal conditioning circuit. The line side interface includes a media coupler that receives the line side media, such as copper media or optical media. The board side interface couples the high-speed serial bit stream interface module to the PCB. A signal conditioning circuit communicatively couples to the line side interface and to the board side interface. The signal conditioning circuit receives an RX signal from the line side interface, conditions the RX signal, and provides the RX signal to the board side interface. The signal conditioning circuit receives a TX signal from the board side interface, conditions the TX signal, and provides the TX signal to the board side interface.

Abstract: A high-speed bit stream interface module interfaces a high-speed communication media to a communication Application Specific Integrated Circuit (ASIC) via a Printed Circuit Board (PCB). The high-speed bit stream interface module includes a line side interface, a board side interface, and a signal conditioning circuit. The line side interface includes a media coupler that receives the line side media, either copper media or optical media. The board side interface couples the high-speed serial bit stream interface module to the PCB. A signal conditioning circuit communicatively couples to the line side interface and to the board side interface. The signal conditioning circuit receives an RX signal from the line side interface, conditions the RX signal, and provides the RX signal to the board side interface. The signal conditioning circuit receives a TX signal from the board side interface, conditions the TX signal, and provides the TX signal to the board side interface.

Abstract: A high-speed bit stream interface module interfaces a high-speed communication media to a communication Application Specific Integrated Circuit (ASIC) via a Printed Circuit Board (PCB). The high-speed bit stream interface includes a line side interface, a board side interface, and a signal conditioning circuit. The signal conditioning circuit services each of an RX path and a TX path and includes a limiting amplifier and a clock and data recovery circuit. The signal conditioning circuit may also include an equalizer and/or an output pre-emphasis circuit. The limiting amplifier applies respective gains to the RX path and to the TX path that are based upon respective dynamic ranges of the incoming signals.

Abstract: A high-speed bit stream interface module interfaces a high-speed communication media to a communication Application Specific Integrated Circuit (ASIC) via a Printed Circuit Board (PCB). The high-speed bit stream interface includes a line side interface, a board side interface, and a signal conditioning circuit. The signal conditioning circuit services each of an RX path and a TX path and includes a limiting amplifier and a clock and data recovery circuit. The signal conditioning circuit may also include an equalizer and/or an output pre-emphasis circuit. The clock and data recovery circuit has an adjustable Phase Locked Loop (PLL) bandwidth that is set to correspond to a jitter bandwidth of a serviced high-speed bit stream.

Abstract: A high-speed bit stream interface module interfaces a high-speed communication media to a communication Application Specific Integrated Circuit (ASIC) via a Printed Circuit Board (PCB). The high-speed bit stream interface includes a line side interface, a board side interface, and a signal conditioning circuit. The signal conditioning circuit services each of an RX path and a TX path and includes a limiting amplifier and a clock and data recovery circuit. The signal conditioning circuit may also include an equalizer and/or an output pre-emphasis circuit. The limiting amplifier applies respective gains to the RX path and to the TX path that are based upon respective dynamic ranges of the incoming signals.

Abstract: Aspects of the invention may provide a method and system for adjusting a gain and/or a frequency response of an input signal for a multimode PHY device. A signal divider (704) may apportion the input signal into a gain adjustment signal and/or an equalization adjustment signal upon receipt of the input signal. A signal adjuster (702) coupled to the signal divider (704) may adjust a gain of the apportioned gain adjustment signal within the multimode PHY device (130). An equalizer (706) coupled to the signal divider (704) may be configured to equalize the equalization adjustment signal within the multimode PHY device (130). A summer (708) coupled to the equalizer (706) and signal adjuster (702) may be adapted to sum the adjusted adjustment signal and the equalized equalization adjustment signal within the multimode PHY device (130) to create an output equalized signal (712) having a desired gain and/or frequency response.

Abstract: Aspects of the invention may provide a method and system for adjusting a gain and/or a frequency response of an input signal for a multimode PHY device. A signal divider may apportion the input signal into a gain adjustment signal and/or an equalization adjustment signal upon receipt of the input signal. A signal adjuster coupled to the signal divider may adjust a gain of the apportioned gain adjustment signal within the multimode PHY device. An equalizer coupled to the signal divider may be configured to equalize the equalization adjustment signal within the multimode PHY device. A summer coupled to the equalizer and signal adjuster may be adapted to sum the adjusted adjustment signal and the equalized equalization adjustment signal within the multimode PHY device to create an output equalized signal having a desired gain and/or frequency response.

Abstract: A high-speed bit stream interface module interfaces a high-speed communication media to a communication Application Specific Integrated Circuit (ASIC) via a Printed Circuit Board (PCB). The high-speed bit stream interface includes a line side interface, a board side interface, and a signal conditioning circuit. The signal conditioning circuit services each of an RX path and a TX path and includes a clock and data recovery circuit and an output pre-emphasis circuit. The output pre-emphasis circuit controllably modifies the spectrum of the high-speed bit stream to pre-compensate for the spectral characteristics of a signal path upon which the high-speed bit stream will be output. In the RX path, pre-compensation is performed based upon the properties of the PCB and a servicing connector. In the TX path, pre-compensation is performed based upon the properties of a line side connector and a line side media.

Abstract: Equalization is provided in a high speed communication receiver that includes in various aspects an automatic gain control input stage, a decision feedback equalizer, a clock and data recovery circuit and equalization control circuits. The automatic gain control stage may include a continuous time filter with an adjustable bandwidth. A threshold adjust signal may be applied to the output of the automatic gain control stage. The equalization control circuits may be implemented in the digital domain and operate at a lower clock speed than the data path.

Abstract: In an integrated decision feedback equalizer and clock and data recovery circuit one or more flip-flops and/or latches may be shared. One or more flip-flops and/or latches may be used in retiming operations in a decision feedback equalizer and in phase detection operations in a clock recovery circuit. Outputs of the flip-flops and/or latches may be used to generate feedback signals for the decision feedback equalizer. The output of a flip-flop and/or latches may be used to generate signals that drive a charge pump in the clock recovery circuit.

Abstract: A circuit and method is disclosed for self trimming in frequency acquisition and clock recovery. The circuit can be simplified as having a VCO in communication with three loops including a trimming loop, a frequency loop and a phase loop. The trimming loop includes a ramp generator for supplying a steady increase of bias current to the VCO causing the frequency of the VCO to increase. At each step, the averaged output of the frequency detector is measured by a comparator. A decision circuit included in the trimming loop registers the output of the comparator in digital format. The trimming loop continues until the decision circuit detects a long string of positives followed by a long string of negatives and at this point, the trimming loop is shut off and the frequency loop is in operation. The frequency loop drives the VCO frequency to within a small difference of the incoming data frequency. The phase loop cleans up the data and locks the phase.

Abstract: Aspects of the invention may provide a method and system for adjusting a gain and/or a frequency response of an input signal for a multimode PHY device. A signal divider (704) may apportion the input signal into a gain adjustment signal and/or an equalization adjustment signal upon receipt of the input signal. A signal adjuster (702) coupled to the signal divider (704) may adjust a gain of the apportioned gain adjustment signal within the multimode PHY device (130). An equalizer (706) coupled to the signal divider (704) may be configured to equalize the equalization adjustment signal within the multimode PHY device (130). A summer (708) coupled to the equalizer (706) and signal adjuster (702) may be adapted to sum the adjusted adjustment signal and the equalized equalization adjustment signal within the multimode PHY device (130) to create an output equalized signal (712) having a desired gain and/or frequency response.