Abstract:
Technology for a phase detector is described. The phase detector can include a reference clock. The phase detector can include a feedback clock. The phase detector can include a first latch operable to set a first latch output depending on a lead-lag status between the reference clock and the feedback clock. The phase detector can include a second latch that loads the lead-lag status when the reference clock and the feedback clock produce clock signals in a high state. The phase detector can include a third latch that loads the lead-lag status from the second latch when the reference clock and the feedback clock produce clock signals in a low state.
Abstract:
An apparatus for setting the timing of a triggering edge of a clock signal with respect to received parallel data. The apparatus includes a set of flip-flops including respective data inputs, respective clock inputs, and respective data outputs, wherein the set of flip-flops are configured to generate a set of output data at the data output based on parallel data applied to the respective data inputs in response to a triggering edge of a clock signal applied to the clock inputs; a variable delay element configured to apply a calibrated delay to the clock signal; and a controller configured to generate a control signal for the variable delay element to apply the calibrated delay to the clock signal based on the set of output data generated at the data outputs of the set of flip-flops.
Abstract:
In one aspect of the teachings herein, a timing circuit detects the assertion of an incoming timing pulse signal at a timing resolution higher than that afforded by the sampling clock signal used to detect the assertion event. To do so, the timing circuit uses delay circuitry to obtain incrementally delayed versions of the incoming timing pulse signal or sampling clock signal. The delay increments are fractions of the sampling clock period and the timing circuit uses the delayed versions to determine a timing difference between actual assertion time of the incoming timing pulse signal and the sampling clock edge at which assertion of the incoming timing pulse signal is detected. In another aspect, a timing circuit uses similar delay techniques to control the timing of an outgoing timing pulse signal at a timing resolution higher than that afforded by the clock circuitry associated with generating the outgoing signal.
Abstract:
The present invention relates to a signal synchronization circuit comprising at least one synchronizer (2.1 - 2.2) comprising a number N of series connected clock delay elements (3.1 - 3.3), N being equal to or greater than unity and a clock signal generator (1) arranged for generating a modulated clock signal adapted to clock the clock delay element (3.1 - 3.3) or elements of the at least one synchronizer (2.1 - 2.2). The clock generator (1) is arranged to receive a clock signal (5) and at least one operating value (6) and to generate the modulated clock signal (1 out) from the clock signal (5) modified based on the operating value (6).
Abstract:
A method involving: distributing two clock signals over a clock signal distribution system; in each of a plurality local clocking regions located along the signal distribution system, detecting the two clock signals and generating therefrom a local clock signal for that local clocking region, wherein the generated local clock signals for at least some of the plurality of local clocking regions are in a first group all of which are aligned in phase with each other and the generated local clock signals for the remainder of the plurality of local clocking regions are in a second group all of which are aligned in phase with each other, and wherein the phase of the first group is out of phase with the phase of the second group by a predetermined amount; and bringing all of the clock signals for the plurality of local clocking regions into phase alignment so that the phase of the first group is in phase with the phase of the second group.
Abstract:
An integrated circuit device includes a delay circuit, sampling circuit and delay control circuit that cooperate to carry out adaptive timing calibration. The delay circuit generates a timing signal by delaying an aperiodic input signal for a first interval. The sampling circuit samples a data signal in response to the timing signal to generate a sequence of data samples, and also samples the data signal in response to a phase-shifted version of the timing signal to generate a sequence of edge samples. The delay control circuit adjusts the first interval based, at least in part, on a phase error indicated by the sequence of data samples and the sequence of edge samples.
Abstract:
A synchronous clock signal can be adjusted relative to a data signal by decreasing a delay in the synchronous clock signal if a transition of a data signal occurs before a pulse of an offset clock signal which is delayed by one half cycle relative to the synchronous clock signal. The synchronous clock signal can be delayed if the transition of the data signal occurs after the pulse of the offset synchronous clock signal.
Abstract:
An IO method and system for bit-deskewing are described. Embodiment includes a computer system with multiple components that transfer data among them. In one embodiment, a system component receives a forward strobe signal and multiple data bit signals from a transmitting component. The receiving component includes a forward strobe clock recovery circuit configurable to align a forward strobe sampling clock so as to improve sampling accuracy. The receiving component further includes at least one data bit clock recovery circuit configurable to align a data bit sampling clock so as to improve sampling accuracy, and to receive a signal from the forward strobe clock recovery circuit that causes the data bit sampling clock to track the forward strobe sampling clock during system operation.