In described examples, a feedback loop has phase detection (PD) circuitry that has a reference input to receive a reference frequency signal, a feedback input to receive a feedback signal, and phase difference outputs. A phase to digital converter (P2DC) includes a first phase to charge converter (PCC) that has a gain polarity and a first phase error output; a second PCC that has an opposite gain polarity and a second phase error output. A differential loop filter has an amplifier with an inverting input coupled to the first phase error output and a non-inverting input coupled to the second phase error output. An analog to digital converter (ADC) has an input coupled to an output of the differential loop filter. A feedback path is coupled to the output of the P2DC, with an output of the feedback path providing the feedback signal to the PD feedback input.

The present disclosure is directed to a digital phase-locked loop frequency synthesizer including: a digitally controlled voltage-controlled oscillator (DCO); a reference oscillator; a digital phase detector; a DCO control module comprising a plurality of registers each arranged to control the frequency of the signal with a predetermined resolution; a first feedback loop arranged to provide a first feedback path between the output of the DCO and the digital phase detector; and a second feedback loop arranged to provide a second feedback path between the first register output and the second register input, the second feedback loop comprising an adder module arranged to change a value of the second register based on the first register output to maximize a DCO frequency output range provided by the first register.

The present disclosure is directed to a digital phase-locked loop frequency synthesizer including: a digitally controlled voltage-controlled oscillator (DCO); a reference oscillator; a digital phase detector; a DCO control module comprising a plurality of registers each arranged to control the frequency of the signal with a predetermined resolution; a first feedback loop arranged to provide a first feedback path between the output of the DCO and the digital phase detector; and a second feedback loop arranged to provide a second feedback path between the first register output and the second register input, the second feedback loop comprising an adder module arranged to change a value of the second register based on the first register output to maximize a DCO frequency output range provided by the first register.

An integrated circuit according to an embodiment of the disclosure may include a plurality of function blocks, a spread spectrum clock (SSC) generator that generates a spread spectrum clock based on a frequency modulation rate value, a clock distribution circuit that distributes the generated spread spectrum clock into the plurality of function blocks, a memory that stores predetermined frequency modulation rate values respectively corresponding to the plurality of function blocks, and a control circuit, and the control circuit may be configured to generate the spread spectrum clock based on a smaller frequency modulation rate value among a first frequency modulation rate value and a second frequency modulation rate value respectively corresponding to a first function block and a second function block, which are operating, from among the plurality of function blocks. Moreover, various embodiment found through the present disclosure are possible.

An integrated circuit according to an embodiment of the disclosure may include a plurality of function blocks, a spread spectrum clock (SSC) generator that generates a spread spectrum clock based on a frequency modulation rate value, a clock distribution circuit that distributes the generated spread spectrum clock into the plurality of function blocks, a memory that stores predetermined frequency modulation rate values respectively corresponding to the plurality of function blocks, and a control circuit, and the control circuit may be configured to generate the spread spectrum clock based on a smaller frequency modulation rate value among a first frequency modulation rate value and a second frequency modulation rate value respectively corresponding to a first function block and a second function block, which are operating, from among the plurality of function blocks. Moreover, various embodiment found through the present disclosure are possible.

Various embodiments of the invention relate to calibrate a wideband segmented Voltage Controlled Oscillator (VCO). Upon initial calibration, information of frequency spanning ranges of each segment in the VCO may be saved into a memory. When the VCO is used or activated, a microcontroller reads data from the memory and applied selected information accordingly. The initial calibration involves a frequency sweep process beginning from a first segment with an initial frequency and records any lock detection (LD) signal to the MCU when a frequency/phase lock is engaged from an unlock status or interrupted from a lock status. With the LD signals, frequency bands of the segments may be calibrated, adjusted for temperature compensated, and finalized after associating adjacent segment frequency overlap zone. A frequency band for a segment may be further segmented into multiple sub-bands with corresponding charge pump currents designated respectively for improved phase lock loop phase noise performance.

Various embodiments of the invention relate to calibrate a wideband segmented Voltage Controlled Oscillator (VCO). Upon initial calibration, information of frequency spanning ranges of each segment in the VCO may be saved into a memory. When the VCO is used or activated, a microcontroller reads data from the memory and applied selected information accordingly. The initial calibration involves a frequency sweep process beginning from a first segment with an initial frequency and records any lock detection (LD) signal to the MCU when a frequency/phase lock is engaged from an unlock status or interrupted from a lock status. With the LD signals, frequency bands of the segments may be calibrated, adjusted for temperature compensated, and finalized after associating adjacent segment frequency overlap zone. A frequency band for a segment may be further segmented into multiple sub-bands with corresponding charge pump currents designated respectively for improved phase lock loop phase noise performance.

A method for providing a jitter signal for modulating a switching frequency of a power switch for a power converter. The method comprising receiving a drive signal representative of the switching frequency of the power switch, detecting the switching frequency from the drive signal, determining if the switching frequency is less than a first threshold frequency, and modulating a frequency of the jitter signal in response to determining if the switching frequency is less than the first threshold frequency.

A method for providing a jitter signal for modulating a switching frequency of a power switch for a power converter. The method comprising receiving a drive signal representative of the switching frequency of the power switch, detecting the switching frequency from the drive signal, determining if the switching frequency is less than a first threshold frequency, and modulating a frequency of the jitter signal in response to determining if the switching frequency is less than the first threshold frequency.

A controller for use in a power converter including a jitter generator circuit coupled to receive a drive signal from a switch controller and generate a jitter signal. The jitter signal is a modulated jitter signal when the drive signal is below a first threshold frequency. The switch controller is coupled to a power switch coupled to an energy transfer element. The switch controller is coupled to receive a current sense signal representative of a current through the power switch. The switch controller is coupled to generate the drive signal to control switching of the power switch in response to the current sense signal and the jitter signal to control a transfer of energy from an input of the power converter to an output of the power converter.