Abstract: A method for a phase-locked loop (PLL) in an integrated circuit, wherein the PLL comprises a voltage-controlled oscillator (VCO). The method includes, in a training mode: (1) setting a control voltage of the VCO at a first voltage level; (2) increasing the control voltage of the VCO from the first voltage level to a second voltage level, until a loss of the feedback signal is detected; and (3) storing an indicator value corresponding to the second voltage level of the control voltage of the VCO. The method further includes, in a normal mode: (1) monitoring a voltage level of the control voltage of the VCO by generating a monitored indicator value corresponding to the voltage level of the control voltage of the VCO; and (2) asserting the loss of feedback signal based on a comparison of the monitored indicator value and the indicator value.

Abstract: A phase locked loop device includes a phase detector that measures a difference in phase between a reference clock signal and an output clock signal provided to a device module. The phase detector provides a pulse having a width indicative of the phase difference. If the phase difference exceeds one of a plurality of threshold values, in indicator can be asserted. Based on the indicator, a control module can take remedial action, such as providing a different clock signal to the device module or triggering an interrupt at a processor device.

Abstract: A phase locked loop device includes a phase detector that measures a difference in phase between a reference clock signal and an output clock signal of the phase locked loop. The phase detector provides a pulse having a width indicative of the phase difference. A phase measurement module determines a digital value based on the pulse width. Accordingly, the digital value provides an indication of the phase difference between the reference clock signal and the output clock signal. A series of the digital values can be recorded to indicate how the phase difference varies over time, thereby providing a useful characterization of device behavior.

Abstract: A phase-locked loop (PLL) system including a phase-frequency detector for generating an up signal or a down signal based on a phase difference between a reference clock and a feedback clock is provided. The PLL system further includes a phase-error spreading circuit for generating phase-spread pulses based on a relationship between a first time attribute of the up signal or the down signal and a second time attribute of the phase-spread pulses. The PLL system further includes a voltage-controlled oscillator (VCO) for generating a VCO clock based on the phase-spread pulses. The PLL system may also include a charge pump that generates a pumping signal based on the phase-spread pulses.

Abstract: A system and method of varying frequency is disclosed. A first oscillator in a phase-locked loop (PLL) maintains a first frequency as part of the PLL lock. A second oscillator having a control coupled to the PLL can be modified to generate a frequency different than that of the PLL. This is accomplished while maintaining lock of the PLL.

Abstract: A system and method of varying frequency is disclosed. A first oscillator in a phase-locked loop (PLL) maintains a first frequency as part of the PLL lock. A second oscillator having a control coupled to the PLL can be modified to generate a frequency different than that of the PLL. This is accomplished while maintaining lock of the PLL.

Abstract: A well bias controller receives input from a sensor. The sensor indicates when a desired threshold condition, such as a temperature or current limit has been exceeded. Threshold conditions are chosen so that when the threshold condition is exceeded, the amount of current drawn by the well bias circuit and through the transistor exceeds the amount of leakage current that would otherwise occur in the device if a well bias circuit were not used. Whenever it is determined, based on the threshold condition, that the well bias circuit is using more current than a device would otherwise leak, the controller turns the well bias circuit off.

Abstract: A well bias controller receives input from a sensor. The sensor indicates when a desired threshold condition, such as a temperature or current limit has been exceeded. Threshold conditions are chosen so that when the threshold condition is exceeded, the amount of current drawn by the well bias circuit and through the transistor exceeds the amount of leakage current that would otherwise occur in the device if a well bias circuit were not used. Whenever it is determined, based on the threshold condition, that the well bias circuit is using more current than a device would otherwise leak, the controller turns the well bias circuit off.