Abstract: A data connector includes two different sets of wires that transport data between components of a computer system. A first set of wires transports data from a first component to a second component. A second set of wires transports data from the second component to the first component. The first set of wires is interlaced with the second set of wires so that each wire in the data connector transports data in the opposite direction of one or more neighboring wires.

Abstract: In a low-power signaling system, an integrated circuit device includes an open loop-clock distribution circuit and a transmit circuit that cooperate to enable high-speed transmission of information-bearing symbols unaccompanied by source-synchronous timing references. The open-loop clock distribution circuit generates a transmit clock signal in response to an externally-supplied clock signal, and the transmit circuit outputs a sequence of symbols onto an external signal line in response to transitions of the transmit clock signal. Each of the symbols is valid at the output of the transmit circuit for a symbol time and a phase offset between the transmit clock signal and the externally-supplied clock signal is permitted to drift by at least the symbol time.

Abstract: In a low-power signaling system, an integrated circuit device includes an open loop-clock distribution circuit and a transmit circuit that cooperate to enable high-speed transmission of information-bearing symbols unaccompanied by source-synchronous timing references. The open-loop clock distribution circuit generates a transmit clock signal in response to an externally-supplied clock signal, and the transmit circuit outputs a sequence of symbols onto an external signal line in response to transitions of the transmit clock signal. Each of the symbols is valid at the output of the transmit circuit for a symbol time and a phase offset between the transmit clock signal and the externally-supplied clock signal is permitted to drift by at least the symbol time.

Abstract: A system and method are provided for tuning a serial link. The method includes receiving, by a receiver circuit, an offset correction pattern transmitted over a serial link and sampling the received offset correction pattern based on an offset correction parameter to generate a sampled signal. A distribution of the sampled signal is computed and the offset correction parameter is set based on the distribution. The system includes a receiver circuit that is coupled to the serial link and an offset correction unit that is coupled to the receiver circuit. The receiver circuit is configured to receive the offset correction pattern and sample the received offset correction pattern based on the offset correction parameter to generate the sampled signal. The offset correction unit is configured to compute the distribution of the sampled signal and set the offset correction parameter based on the distribution.

Abstract: A system is provided for transmitting signals. The system comprises a first processing unit, a cache memory, and a package. The first processing unit comprises a first ground-referenced single-ended signaling (GRS) interface circuit and the second processing unit comprises a second GRS interface circuit. The cache memory comprises a third and a fourth GRS interface circuit. The package comprises one or more electrical traces that couple the first GRS interface to the third GRS interface and couple the second GRS interface to the fourth GRS interface, where the first GRS interface circuit, the second GRS interface, the third GRS interface, and the fourth GRS interface circuit are each configured to transmit a pulse along one trace of the one or more electrical traces by discharging a capacitor between the one trace and a ground network.

Abstract: A system of interconnected chips comprising a multi-chip module (MCM) includes a first processor chip, a second processor chip, and an MCM package configured to include the first processor chip, the second processor chip, and an interconnect circuit. The first processor chip is configured to include a first ground-referenced single-ended signaling (GRS) interface circuit. A first set of electrical traces fabricated within the MCM package and configured to couple the first GRS interface circuit to the interconnect circuit. The second processor chip is configured to include a second GRS interface circuit. A second set of electrical traces fabricated within the MCM package and configured to coupled the second GRS interface circuit to the interconnect circuit.

Abstract: A system is provided for transmitting signals. The system comprises a first processing unit, a memory subsystem, and a package. The first processing unit is configured to include a first ground-referenced single-ended signaling (GRS) interface circuit. The memory subsystem is configured to include a second GRS interface circuit. The package is configured to include one or more electrical traces that couple the first GRS interface to the second GRS interface, where the first GRS interface circuit and the second GRS interface circuit are each configured to transmit a pulse along one trace of the one or more electrical traces by discharging a capacitor between the one trace and a ground network.

Abstract: A system includes a control circuit and first, second, and third ground-referenced single-ended signaling (GRS) driver circuits that are each coupled to an output signal. The control circuit is configured to generate a first, second, and third set of control signals that are each based on a respective phase of a clock signal. Each GRS driver circuit is configured to pre-charge a capacitor to store a charge based on the respective set of control signals during at least one phase of the clock signal and drive the output signal relative to a ground network by discharging the charge during a respective phase of the clock signal.

Abstract: A system of interconnected chips comprising a multi-chip module (MCM) includes a first processor chip, a system function chip, and an MCM package configured to include the first processor chip and the system function chip. The first processor chip is configured to include a first ground-referenced single-ended signaling (GRS) interface circuit. The system function chip is configured to include a second GRS interface circuit. A first set of electrical traces are fabricated within the MCM package and coupled to the first GRS interface circuit and to the second GRS interface circuit. The first GRS interface circuit and second GRS interface circuit together provide a communication channel between the first processor chip and the system function chip.

Abstract: A system of interconnected chips comprising a multi-chip module (MCM) includes a first processor chip, a second processor chip, and an MCM package configured to include the first processor chip, the second processor chip, and an interconnect circuit. The first processor chip is configured to include a first ground-referenced single-ended signaling (GRS) interface circuit. A first set of electrical traces fabricated within the MCM package and configured to couple the first GRS interface circuit to the interconnect circuit. The second processor chip is configured to include a second GRS interface circuit. A second set of electrical traces fabricated within the MCM package and configured to coupled the second GRS interface circuit to the interconnect circuit.

Abstract: A system of interconnected chips comprising a multi-chip module (MCM) includes a first processor chip, a graphics processing cluster (GPC) chip, and an MCM package configured to include the first processor chip, the GPC chip, and an interconnect circuit. The first processor chip is configured to include a first ground-referenced single-ended signaling interface circuit. A first set of electrical traces fabricated within the MCM package and configured to couple the first single-ended signaling interface circuit to the interconnect circuit. The GPC chip is configured to include a second single-ended signaling interface circuit and to execute shader programs. A second set of electrical traces fabricated within the MCM package and configured to couple the second single-ended signaling interface circuit to the interconnect circuit. In one embodiment, each single-ended signaling interface advantageously implements ground-referenced single-ended signaling.

Abstract: A system of interconnected chips comprising a multi-chip module (MCM) includes a processor chip, a system functions chip, and an MCM package configured to include the processor chip, the system functions chip, and an interconnect circuit. The processor chip is configured to include a first ground-referenced single-ended signaling interface circuit. A first set of electrical traces manufactured within the MCM package and configured to couple the first single-ended signaling interface circuit to the interconnect circuit. The system functions chip is configured to include a second single-ended signaling interface circuit and a host interface. A second set of electrical traces manufactured within the MCM package and configured to couple the host interface to at least one external pin of the MCM package. In one embodiment, each single-, ended signaling interface advantageously implements ground-referenced single-ended signaling.

Abstract: In a low-power signaling system, an integrated circuit device includes an open loop-clock distribution circuit and a transmit circuit that cooperate to enable high-speed transmission of information-bearing symbols unaccompanied by source-synchronous timing references. The open-loop clock distribution circuit generates a transmit clock signal in response to an externally-supplied clock signal, and the transmit circuit outputs a sequence of symbols onto an external signal line in response to transitions of the transmit clock signal. Each of the symbols is valid at the output of the transmit circuit for a symbol time and a phase offset between the transmit clock signal and the externally-supplied clock signal is permitted to drift by at least the symbol time.

Abstract: A single-ended data transmission system transmits a signal having a signal voltage that is referenced to a power supply voltage and that swings above and below the power supply voltage. The power supply voltage is coupled to a power supply rail that also serves as a signal return path. The signal voltage is derived from two signal supply voltages generated by a pair of charge pumps that draw substantially same amount of current from a power supply.

Abstract: An 8-transistor SRAM (static random access memory) storage cell provides differential read bit lines that are precharged to a low voltage level for read operations. The 8-transistor storage cell provides separate ports for read and write operations, including differential read bit lines. Prior to each read operation, the differential read bit lines are precharged to the low voltage level. During read operations, one of the two differential read bit lines is pulled high towards a high voltage level while the complementary bit line remains at the low voltage level resulting from the precharge. The difference in voltage between the differential read bit lines is sensed to determine the value stored in each 8-transistor SRAM storage cell and complete the read operation.

Abstract: One embodiment sets forth a technique for on-chip satisfying timing requirements of on-chip source-synchronous, CMOS-repeater-based interconnect. Each channel of the on-chip interconnect may include one or more redundant wires. Calibration logic is configured to apply transition patterns to wires comprising each channel and calibration patterns that are generated in response to the transition patterns are captured. Based on the calibration patterns, wires that best satisfy the timing requirements of the on-chip interconnect are selected for use to transmit data. The calibration logic also trims the delays of the clock and selected data wires based on captured calibration patterns to improve the timing margin of the on-chip interconnect. Improving the timing margin of the on-chip interconnect improves chip yields.

Abstract: One embodiment sets forth a technique for delaying signals by varying amounts. A configurable delay circuit includes fixed and tri-state inverters. Pullup and pulldown transistors within one or more tri-state inverters may be activated to reduce the delay introduced by fixed inverters. The pullup and pulldown transistors within one or more tri-state inverters may be separately activated to independently adjust the rising delay and the falling delay incurred by the input signal.

Abstract: An integrated circuit receiver includes a first channel comprising an amplifier responsive to a first gain control value in a first mode to receive an input signal and generate a first amplified signal having a transition rate. Detection circuitry in the first channel detects transitions in the first amplified signal in accordance with a detected transition rate. The detected transition rate is based on the first gain control value. Gain control logic adjusts the first gain control value based on a desired detected transition rate. The gain control logic generates a second gain control value for use during a second mode. The second gain control value being based on the first gain control value.

Abstract: One embodiment sets forth a technique for on-chip satisfying timing requirements of on-chip source-synchronous, CMOS-repeater-based interconnect. Each channel of the on-chip interconnect may include one or more redundant wires. Calibration logic is configured to apply transition patterns to wires comprising each channel and calibration patterns that are generated in response to the transition patterns are captured. Based on the calibration patterns, wires that best satisfy the timing requirements of the on-chip interconnect are selected for use to transmit data. The calibration logic also trims the delays of the clock and selected data wires based on captured calibration patterns to improve the timing margin of the on-chip interconnect. Improving the timing margin of the on-chip interconnect improves chip yields.

Abstract: One embodiment sets forth a timing calibration technique for on-chip source-synchronous, complementary metal-oxide-semiconductor (CMOS) repeater-based interconnect. Two transition patterns may be applied to calibrate the delay of an on-chip data or clock wire. Calibration logic is configured to apply the transition patterns and then trim the delays of the clock and data wires based on captured calibration patterns. The trimming adjusts the delay of the clock and data wires using a configurable delay circuit. Timing errors may be caused by crosstalk, power-supply-induced jitter (PSIJ), or wire delay variation due to transistor and wire metallization mismatch. Chip yields may be improved by reducing the occurrence of timing errors due to mismatched delays between different wires of an on-chip interconnect.