Abstract: Input/output (I/O) clock phase adjustment circuitry for use with I/O buffer circuitry of an integrated circuit chip. In one embodiment, an integrated circuit chip includes a phase adjustment circuit coupled to receive a system clock. The phase adjustment circuit generates an I/O clock coupled to be received by an I/O buffer circuit of an integrated circuit chip for I/O data transfers in a system. The phase adjustment circuit includes a phase locked loop (PLL) circuit coupled to receive the system clock through a first delay circuit. The I/O clock generated by the PLL circuit is received through a second delay circuit at a feedback clock input of the PLL circuit. The first and second delay circuits are used to control the phase of the I/O clock generated by the PLL circuit relative to the system clock. In one embodiment, a third delay circuit is included in an I/O data path of the I/O buffer circuit of the integrated circuit.

Abstract: An apparatus and method are provided for operating a processor core. This may include a first circuit to operate at a frequency that is dependent on a power supply voltage. A frequency control circuit may be provided to control a frequency of the first circuit by directing a voltage regulator to increase or decrease the power supply voltage.

Abstract: A single external impedance element is used to perform multiple circuit compensation. A reference impedance code is first generated from a master circuit, and then the reference impedance code is shifted to generate a slave impedance code. The slave impedance code is provided to one or more slave circuits to activate devices in the slave circuit(s). Impedance-generation devices coupled to the slave circuit are then activated one at a time until their generated impedance corresponds to the impedance generated by the slave circuit. The reference impedance code can be incremented or decremented (e.g., shifted) to generate slave impedance codes corresponding to different impedance values, according to impedance requirements of various different circuits that require compensation.

Abstract: A processor having asymmetric secondary processing resources. One disclosed embodiment includes a first execution resource to perform a first function and a second execution resource that also performs the second function, although the second processing resource is asymmetric to the first resource in that it has a lower throughput than the first processing resource. Switching logic switches execution from the first processing resource to the second processing resource in a reduced power consumption mode.

Abstract: A method and apparatus for jitter reduction in a Phase Locked Loop (PLL) that includes determining a size of a original charge pump adequate to generate an appropriate control voltage to a Voltage Controlled Oscillator (VCO) of a PLL based on the charge pump receiving a single up signal or down signal within one cycle of a PLL input reference clock. N number of the up signal or down signal are generated to a second charge pump 1/N the size of the original charge pump. The N number of the up signal or the down signal occurs within one cycle of the PLL input reference clock. The second charge pump generates N second control voltage corrections each being 1/N the amplitude of the appropriate control voltage glitch, thus minimizing glitches on the second control voltages and reducing jitter to the VCO.

Abstract: A clock generating circuit is provided that includes a plurality of distributed ring oscillators to drive a clock distribution network. Multiplexing devices may select a length or delay of each of the ring oscillators. The variable length or delay may thereby adjust the frequency of the clock generating circuit.

Abstract: An apparatus and method are provided for operating a processor core. This may include a first circuit to operate at a frequency that is dependent on a power supply voltage. A frequency control circuit may be provided to control a frequency of the first circuit by directing a voltage regulator to increase or decrease the power supply voltage.

Abstract: A lock detector system which operates adaptively based on a frequency of operation. Different lock windows are defined for different frequencies of operation and are automatically formed based on the controlled signal that is used to drive the voltage controlled oscillator of the phase locked loop.

Abstract: A single external impedance element is used to perform multiple circuit compensation. A reference impedance code is first generated based on matching an internal impedance generated by transistors with an impedance of the external impedance element, and then the reference impedance code can be shifted to generate new impedance codes according to impedance requirements of various different circuits that require compensation. Use of the single external impedance element for compensation of multiple circuits reduces motherboard and packaging costs. Chip area is also conserved since simpler compensation circuits can be used.

Abstract: A single external impedance element is used to perform multiple circuit compensation. A reference impedance code is first generated from a master circuit, and then the reference impedance code is shifted to generate a slave impedance code. The slave impedance code is provided to one or more slave circuits to activate devices in the slave circuit(s). Impedance-generation devices coupled to the slave circuit are then activated one at a time until their generated impedance corresponds to the impedance generated by the slave circuit. The reference impedance code can be incremented or decremented (e.g., shifted) to generate slave impedance codes corresponding to different impedance values, according to impedance requirements of various different circuits that require compensation.

Abstract: A single external impedance element is used to perform multiple circuit compensation. A reference impedance code is first generated based on matching an internal impedance generated by transistors with an impedance of the external impedance element, and then the reference impedance code can be shifted to generate new impedance codes according to impedance requirements of various different circuits that require compensation. Use of the single external impedance element for compensation of multiple circuits reduces motherboard and packaging costs. Chip area is also conserved since simpler compensation circuits can be used.

Abstract: A method transfers a signal from a transmitting device to a receiving device. The signal is output from the transmitting device using a driving circuit. A reference clock signal is received in the transmitting device. An output clock signal is generated according to the received reference clock signal and a feedback clock signal in a phase locked loop. A delay is provided in a path of the reference clock signal and a path of the feedback clock signal. The delay is configured to make the output signal meet a predetermined valid data timing requirement.

Abstract: A single external impedance element is used to perform multiple circuit compensation. A reference impedance code is first generated from a master circuit, and then the reference impedance code is provided (as a slave impedance code) to one or more slave circuits to activate devices in the slave circuit(s). Impedance-generation devices coupled to the slave circuit are then activated one at a time until their generated impedance corresponds to the impedance generated by the slave circuit. The reference impedance code can be incremented or decremented (e.g., shifted) to generate slave impedance codes corresponding to different impedance values, according to impedance requirements of various different circuits that require compensation. Using the single external impedance element for compensation of multiple circuits reduces motherboard and packaging costs.

Abstract: A circuit board has a transmission line. A connector is coupled to the circuit board and electrically coupled to the transmission line. Bus termination circuitry is electrically coupled to the transmission line at or near an end of the transmission line at the connector such that the transmission line is terminated by the bus termination circuitry when the connector is not engaged to support any device for electrical coupling to the transmission line.

Abstract: A technique for compensating a characteristic, such as a resistance, of at least one circuit includes selectively incrementing a characteristic of a dummy circuit and comparing it with a characteristic of an external reference to generate a reference code. A previous reference code is stored and subsequently compared with a present reference code. It is ensured that the present reference code differs by no more than a predetermined amount from the stored previous reference code by ceasing the incrementing or decrementing of the characteristic of the dummy circuit and utilizing the present reference code to compensate the characteristic of the at least one circuit.

Abstract: A circuit board has a transmission line. A connector is coupled to the circuit board and electrically coupled to the transmission line. Bus termination circuitry is electrically coupled to the transmission line at or near an end of the transmission line at the connector such that the transmission line is terminated by the bus termination circuitry when the connector is not engaged to support any device for electrical coupling to the transmission line.

Abstract: A lock detector system which operates adaptively based on a frequency of operation. Different lock windows are defined for different frequencies of operation and are automatically formed based on the controlled signal that is used to drive the voltage controlled oscillator of the phase locked loop.

Abstract: A single external impedance element is used to perform multiple circuit compensation. A reference impedance code is first generated based on matching an internal impedance generated by transistors with an impedance of the external impedance element, and then the reference impedance code can be shifted to generate new impedance codes according to impedance requirements of various different circuits that require compensation. Use of the single external impedance element for compensation of multiple circuits reduces motherboard and packaging costs. Chip area is also conserved since simpler compensation circuits can be used.

Abstract: A single external impedance element is used to perform multiple circuit compensation. A reference impedance code is first generated from a master circuit, and then the reference impedance code is provided (as a slave impedance code) to one or more slave circuits to activate devices in the slave circuit(s). Impedance-generation devices coupled to the slave circuit are then activated one at a time until their generated impedance corresponds to the impedance generated by the slave circuit. The reference impedance code can be incremented or decremented (e.g., shifted) to generate slave impedance codes corresponding to different impedance values, according to impedance requirements of various different circuits that require compensation. Using the single external impedance element for compensation of multiple circuits reduces motherboard and packaging costs.

Abstract: A pull-up circuit has substantially linear current-voltage (I-V) characteristics for use in a bus system, such as in an open drain bus architecture type system. Operation in the linear region of the I-V characteristics is useful in high frequency input/output circuits. The pull-up circuit includes a transistor and a single termination resistor coupled to the transistor, and is simpler than other types of pull-up circuits. This simplicity in design saves area on a chip. The termination resistor in the pull-up circuit can be an n-well resistor formed on the same chip as the transistor, thereby further contributing to the savings in chip area.