A method of measuring phase noise (PN). A PLL frequency synthesizer is provided including a first phase frequency detector (PFD) receiving a reference frequency signal coupled to a first charge pump (CP) coupled to a VCO having an output fedback to the first PFD through a feedback divider that provides a divided frequency signal to the first PFD which outputs an error signal, and PN measurement circuitry including a replica CP coupled to an output of a second PFD or the first PFD. The error signal is received at the replica CP or the divided and reference frequency signal are received at the second PFD, wherein the replica CP outputs a scaled phase error current which is current-to-voltage converted and amplified to provide an amplified phase error voltage, and digitized to provide a digital phase error signal. The digital phase error signal is frequency analyzed to generate a PN measurement.

An IC, operable at a first clock phase, includes first and second IOs and a PLL. The PLL includes a control circuit, an input to receive a first clock signal, an output to output a second clock signal, and a first detector to generate a first phase difference signal from the first and second clock signals. The IC includes a second phase detector that is coupled to the PLL's output to receive the second clock signal and is coupled to the first IO to receive a third clock single from a second IC, which is operable at a second clock phase. The second detector generates a second phase difference signal from the second and third clock signals. If the PLL uses the second phase difference signal to generate the second clock signal, then the second clock signal is synchronized with the third clock signal for synchronous data transfer.

An IC, operable at a first clock phase, includes first and second IOs and a PLL. The PLL includes a control circuit, an input to receive a first clock signal, an output to output a second clock signal, and a first detector to generate a first phase difference signal from the first and second clock signals. The IC includes a second phase detector that is coupled to the PLL's output to receive the second clock signal and is coupled to the first IO to receive a third clock single from a second IC, which is operable at a second clock phase. The second detector generates a second phase difference signal from the second and third clock signals. If the PLL uses the second phase difference signal to generate the second clock signal, then the second clock signal is synchronized with the third clock signal for synchronous data transfer.

A frequency divider circuit is provided. The frequency divider circuit processes multiple input clocks. The frequency divider circuit includes a frequency dividing circuit and a retiming circuit. The frequency dividing circuit generates an intermediate clock according to a first subgroup of the input clocks. The retiming circuit generates multiple output clocks according to a second subgroup of the input clocks and the intermediate clock. The periods of the input clocks are all a first period, and the periods of the output clocks are all a second period. The first period is smaller than the second period. The frequency dividing circuit and the retiming circuit operate according to a mode control signal which determines a ratio of the first period to the second period.

A circuit device includes an oscillation circuit configured to generate an oscillation signal using a resonator, a temperature sensor circuit configured to output temperature detection data, a temperature compensation circuit configured to perform, based on the temperature detection data, temperature compensation on an oscillation frequency of the oscillation signal, a memory configured to store correction data for correcting the temperature detection data to obtain a temperature, and an interface circuit configured to output the temperature detection data and the correction data.

A system of free running oscillators synchronized to the lowest frequency running one and following PVT variation generates a system clock. A method is particularly applicable to clock relatively small clock domains within a multi-core chip containing thousands of cores, and where the clock domain encompasses one or more cores and additional logic blocks. The resulting system clock is divided by 2.sup.k using latches or flip-flops to achieve a symmetric 50-50 duty cycle of the system clock. Further, such PVT insensitive system clock can be used as a reference for a PLL or DLL generated clock for the domain.

A system of free running oscillators synchronized to the lowest frequency running one and following PVT variation generates a system clock. A method is particularly applicable to clock relatively small clock domains within a multi-core chip containing thousands of cores, and where the clock domain encompasses one or more cores and additional logic blocks. The resulting system clock is divided by 2.sup.k using latches or flip-flops to achieve a symmetric 50-50 duty cycle of the system clock. Further, such PVT insensitive system clock can be used as a reference for a PLL or DLL generated clock for the domain.

A two-chip die module with minimal chip-to-chip clock skew is provided. The two-chip die module includes a common substrate, first and second chips operably disposed on the common substrate to be communicative in parallel with one another and a single phase lock loop (PLL). The PLL is disposed within one of the first and second chips to provide a source for a common clock signal for the first and second chips. PLL signals of the PLL to the first and second chips are nearly equal and clock sample signals of the first and second chips are nearly equal.

A display driving device and an anti-interference method thereof are provided. A timing controller outputs a data signal. A source driver detects an interference event according to the data signal, and outputs a feedback signal to the timing controller in response to the detection result of the interference event. The timing controller adjusts the signal strength of the data signal according to the feedback signal.

A display driving device and an anti-interference method thereof are provided. A timing controller outputs a data signal. A source driver detects an interference event according to the data signal, and outputs a feedback signal to the timing controller in response to the detection result of the interference event. The timing controller adjusts the signal strength of the data signal according to the feedback signal.