Abstract: Embodiments are disclosed that relate to multi-phase clock generators and data samplers for use in high speed I/O circuitry. One disclosed example provides a multi-phase clock generator including a delay line having a plurality of delay elements, the delay line being configured to receive an input clock signal and output a plurality of output clock signals having different phases compared to a phase of the input clock signal. The multi-phase clock generator further includes a control circuit configured to control the delay line based at least in part upon rising edges and falling edges of one or more output clock signals output at one or more locations along the delay line.

Abstract: In embodiments of a serializing transmitter, the serializing transmitter includes N multiplexing drive units, each configured to generate a series of output pulses derived from input data signals and multi-phase clock signals, and each multiplexing drive unit including a pulse-controlled push-pull output driver having first and second inputs and an output. Each multiplexing driver unit further includes a first M:1 pulse-generating multiplexer having an output coupled to the first input of the pulse-controlled push-pull output driver, and a second M:1 pulse-generating multiplexer having an output coupled to the second input of the pulse-controlled push-pull output driver, wherein each of the first and second M:1 pulse-generating multiplexers has three or fewer gate delays from a clock input to an output of the pulse-generating multiplexer.

Abstract: A signal sampling system that includes N samplers is disclosed. Each sampler includes a data input having a decision logic level threshold, a plurality of offset control inputs, a plurality of offset magnitude inputs, an un-buffered output, and a buffered output. Each sampler further includes circuitry coupled between the inputs and outputs that is configured to cause a time delay from an input signal transition to an output signal transition such that, after an offset control input transitions from a first voltage to a second voltage, the decision logic level threshold changes in a time substantially less than one gate delay, and after the sample clock transitions from a first logic state to a second logic state, the un-buffered output transitions within a time substantially equal to one gate delay and the buffered output transitions within a time substantially equal to two gate delays.

Abstract: In embodiments of a serializing transmitter, the serializing transmitter includes N multiplexing drive units, each configured to generate a series of output pulses derived from input data signals and multi-phase clock signals, and each multiplexing drive unit including a pulse-controlled push-pull output driver having first and second inputs and an output. Each multiplexing driver unit further includes a first M:1 pulse-generating multiplexer having an output coupled to the first input of the pulse-controlled push-pull output driver, and a second M:1 pulse-generating multiplexer having an output coupled to the second input of the pulse-controlled push-pull output driver, wherein each of the first and second M:1 pulse-generating multiplexers has four or fewer clock inputs.

Abstract: A signal sampling system that includes N samplers is disclosed. Each sampler includes a data input having a decision logic level threshold, a plurality of offset control inputs, a plurality of offset magnitude inputs, an un-buffered output, and a buffered output. Each sampler further includes circuitry coupled between the inputs and outputs that is configured to cause a time delay from an input signal transition to an output signal transition such that, after an offset control input transitions from a first voltage to a second voltage, the decision logic level threshold changes in a time substantially less than one gate delay, and after the sample clock transitions from a first logic state to a second logic state, the un-buffered output transitions within a time substantially equal to one gate delay and the buffered output transitions within a time substantially equal to two gate delays.

Abstract: In embodiments of a serializing transmitter, the serializing transmitter includes N multiplexing drive units, each configured to generate a series of output pulses derived from input data signals and multi-phase clock signals, and each multiplexing drive unit including a pulse-controlled push-pull output driver having first and second inputs and an output. Each multiplexing driver unit further includes a first M:1 pulse-generating multiplexer having an output coupled to the first input of the pulse-controlled push-pull output driver, and a second M:1 pulse-generating multiplexer having an output coupled to the second input of the pulse-controlled push-pull output driver, wherein each of the first and second M:1 pulse-generating multiplexers has three or fewer gate delays from a clock input to an output of the pulse-generating multiplexer.

Abstract: In embodiments of a serializing transmitter, the serializing transmitter includes N multiplexing drive units, each configured to generate a series of output pulses derived from input data signals and multi-phase clock signals, and each multiplexing drive unit including a pulse-controlled push-pull output driver having first and second inputs and an output. Each multiplexing driver unit further includes a first M:1 pulse-generating multiplexer having an output coupled to the first input of the pulse-controlled push-pull output driver, and a second M:1 pulse-generating multiplexer having an output coupled to the second input of the pulse-controlled push-pull output driver, wherein each of the first and second M:1 pulse-generating multiplexers has four or fewer clock inputs.

Abstract: In embodiments of a high-speed I/O data system, a first computer chip includes a data transmission system, and a second computer chip includes a data reception system. A data channel communicates an NRZ data signal, and a clock channel communicates a forwarded clock signal, from the data transmission system to the data reception system. The data transmission system includes a first differential serializing transmitter to generate the NRZ data signal from pulsed data, and further includes a second differential serializing transmitter to generate a forwarded clock signal. A first multi-phase transmit clock generator generates transmit clock signals for the first and second differential serializing transmitters. The data reception system includes a data receiver and a de-serializer to receive and de-serialize the NRZ data signal, and includes a multi-phase receive clock generator to generate receive clock signals from the forwarded clock signal for the de-serializing data receiver.

Abstract: Embodiments are disclosed that relate to multi-phase clock generators and data samplers for use in high speed I/O circuitry. One disclosed example provides a multi-phase clock generator including a delay line having a plurality of delay elements, the delay line being configured to receive an input clock signal and output a plurality of output clock signals having different phases compared to a phase of the input clock signal. The multi-phase clock generator further includes a control circuit configured to control the delay line based at least in part upon rising edges and falling edges of one or more output clock signals output at one or more locations along the delay line.

Abstract: In embodiments of a high-speed I/O data system, a first computer chip includes a data transmission system, and a second computer chip includes a data reception system. A data channel communicates an NRZ data signal, and a clock channel communicates a forwarded clock signal, from the data transmission system to the data reception system. The data transmission system includes a first differential serializing transmitter to generate the NRZ data signal from pulsed data, and further includes a second differential serializing transmitter to generate a forwarded clock signal. A first multi-phase transmit clock generator generates transmit clock signals for the first and second differential serializing transmitters. The data reception system includes a data receiver and a de-serializer to receive and de-serialize the NRZ data signal, and includes a multi-phase receive clock generator to generate receive clock signals from the forwarded clock signal for the de-serializing data receiver.

Abstract: In embodiments of a high-speed I/O data system, a first computer chip includes a data transmission system, and a second computer chip includes a data reception system. A data channel communicates an NRZ data signal, and a clock channel communicates a forwarded clock signal, from the data transmission system to the data reception system. The data transmission system includes a first differential serializing transmitter to generate the NRZ data signal from pulsed data, and further includes a second differential serializing transmitter to generate a forwarded clock signal. A first multi-phase transmit clock generator generates transmit clock signals for the first and second differential serializing transmitters. The data reception system includes a data receiver and a de-serializer to receive and de-serialize the NRZ data signal, and includes a multi-phase receive clock generator to generate receive clock signals from the forwarded clock signal for the de-serializing data receiver.

Abstract: In embodiments of a serializing transmitter, the serializing transmitter includes one or more multiplexing drive units that each generate a series of output pulses derived from input data signals and multi-phase clock signals. Each of the multiplexing drive units includes a pulse-controlled push-pull output driver that has first and second inputs, and an output coupled to an output of the multiplexing drive unit. Each of the multiplexing drive units also includes a first M:1 (where M is two or more) pulse-generating multiplexer having an output coupled to the first input of the pulse-controlled push-pull output driver, and generating a first series of intermediate pulses at the output; and a second M:1 pulse-generating multiplexer having an output coupled to the second input of the pulse-controlled push-pull output driver, and generating a second series of intermediate pulses at the output.

Abstract: In embodiments of a high-speed I/O data system, a first computer chip includes a data transmission system, and a second computer chip includes a data reception system. A data channel communicates an NRZ data signal, and a clock channel communicates a forwarded clock signal, from the data transmission system to the data reception system. The data transmission system includes a first differential serializing transmitter to generate the NRZ data signal from pulsed data, and further includes a second differential serializing transmitter to generate a forwarded clock signal. A first multi-phase transmit clock generator generates transmit clock signals for the first and second differential serializing transmitters. The data reception system includes a data receiver and a de-serializer to receive and de-serialize the NRZ data signal, and includes a multi-phase receive clock generator to generate receive clock signals from the forwarded clock signal for the de-serializing data receiver.

Abstract: In embodiments of a serializing transmitter, the serializing transmitter includes one or more multiplexing drive units that each generate a series of output pulses derived from input data signals and multi-phase clock signals. Each of the multiplexing drive units includes a pulse-controlled push-pull output driver that has first and second inputs, and an output coupled to an output of the multiplexing drive unit. Each of the multiplexing drive units also includes a first M:1 (where M is two or more) pulse-generating multiplexer having an output coupled to the first input of the pulse-controlled push-pull output driver, and generating a first series of intermediate pulses at the output; and a second M:1 pulse-generating multiplexer having an output coupled to the second input of the pulse-controlled push-pull output driver, and generating a second series of intermediate pulses at the output.

Abstract: A multi-phase clock generator circuit receives an input clock signal and produces multiple output clock signal, each from a respective delay stage of a multi-stage voltage-controlled delay line (VCDL). The rising edges of the multiple output clock signals produced by the circuit are substantially equidistant in time from one another and have substantially equal phase spacing.

Abstract: A multi-phase correction circuit adjusts the phase relationship among multiple clock signals such that their rising edges are equidistant in time from one another.

Abstract: A multi-phase clock generator circuit receives an input clock signal and produces multiple output clock signal, each from a respective delay stage of a multi-stage voltage-controlled delay line (VCDL). The rising edges of the multiple output clock signals produced by the circuit are substantially equidistant in time from one another and have substantially equal phase spacing.

Abstract: A multi-phase correction circuit adjusts the phase relationship among multiple clock signals such that their rising edges are equidistant in time from one another.

Abstract: A serial data communication receiver includes a serial data input and a termination resistance, which is coupled to the serial data input and is variable over a range of termination resistance values. An equalizer circuit is coupled to the serial data input and has an equalized serial data output. First and second capture latch circuits are coupled to the equalized serial data output, within a phase-locked loop, and have first and second recovered data outputs, respectively. A termination resistance control circuit measures a data eye size of the equalized serial data output based on the first and second recovered data outputs over the range of termination resistance values and sets the termination resistance to one of the termination resistance values based on the measured data eye sizes.

Abstract: A serial data communication receiver includes a serial data input, first and second equalizers, first and second capture latch circuits, and an equalization control circuit. The first and second equalizers are coupled to the serial data input and have first and second equalized serial data outputs, respectively. Each equalizer has a frequency response that is variable over a range of frequency response settings. The first and second capture latch circuits are coupled to the first and second equalized serial data outputs, respectively, in a phase-locked loop and have first and second recovered data outputs, respectively. The equalization control circuit measures a data eye size of the second equalized serial data output over the range of frequency response settings of the second equalizer and sets the frequency response of the first equalizer to one of the frequency response settings based on the measured data eye sizes.