Abstract: An apparatus is disclosed which includes a signal generator providing a first signal having a first frequency; a clock tree operative to propagate the first signal to at least one clock mesh of the apparatus; and a final buffer operative to receive the first signal, provide a second signal having a second frequency, synchronize the second signal with the first signal, and propagate the synchronized second signal to at least one other clock mesh of the apparatus.

Abstract: Systems and methods for circuits with substantially equal propagation delay while providing different drive strengths are disclosed. These systems and methods may allow for a circuit with a drive strength that is some ratio of an arbitrary strength full drive strength circuit. Additionally, these circuits may have substantially the same input capacitance and feedback current as the baseline drive circuit. The input of such a circuit may be coupled to three nodes, one of which is an inverter coupled to the logic to be driven, the second of which is dummy logic, and the third of which is an inverter the output of which is left floating.

Abstract: An apparatus, a method, and a computer program are provided to disable clock distribution. In microprocessors, the clock distribution system can account for a substantial amount of power consumption. Disabling the clock distribution system, however, has been difficult because of the usual requirement for a separate clock for control logic. Therefore, combinational logic can be employed to disrupt the clock distribution and allow a processor to be awakened without a need for a separate clock.

Abstract: An apparatus, a method, and a computer program are provided to gate a Phased Locked Loop (PLL). In microprocessors, the clock distribution system can account for a substantial amount of power consumption. Gating the PLLs, however, has been difficult because of the usual requirement for a separate clock for control logic and because the PLL requires timed to reacquire phase/frequency lock. Therefore, lock detection logic can be employed to allow the PLL to reacquire phase/frequency lock. Additionally, signals from external devices and the processor can be employed to gate the PLL and allow the processor to be awakened without a need for a separate clock.

Abstract: The present invention provides for reducing current spikes in a circuit when changing clocking frequencies. A first frequency is applied to a clock distribution network. A final frequency is selected. The first frequency is applied to a logic element over the clock distribution network. A hold signal is applied to the logic element. The clock rate of the clock distribution network is changed from the first frequency to the final frequency. The hold signal is unapplied to the logic element.

Abstract: The present invention discloses, in one aspect, a synchronizing circuit for synchronizing transmitted data. In one embodiment, the synchronization technique comprises a subsystem configured to compare positive and negative transitions of a core clock signal with positive and negative transitions of a source clock signal to determine a relationship between the transitions of the core clock signal and positions of the negative transitions of the source clock signal. The synchronization circuit also comprises logic circuitry coupled to the subsystem and configured to generate a final sampling signal based on the relationship. In addition, the synchronization circuit comprises a data sampler coupled to the logic circuitry and configured to sample a source data signal synchronized with the source clock signal using the final sampling signal, and to generate a core data signal synchronized with the core clock signal based on the sampling.

Abstract: A bridge for interfacing buses in a computer system having an industry standard architecture (ISA) bus and a peripheral controller interconnect (PCI) bus is coupled between the ISA and PCI buses. Devices coupled to the buses are either PCI bus-compliant devices or are non-PCI bus-compliant devices. A power management device in the computer system is able to place the computer system into a low power suspend mode, a resume mode and an active mode. The bridge has a multi-tiered arbitration device for arbitrating among the PCI bus-compliant devices and the non-PCI bus-compliant devices for control of the computer system. The arbitration device is responsive to the power management device to controllably suspend arbitration when the power management device indicates that the suspend mode is being entered.