A frequency generator, includes a control unit, configured to receive an input signal to generate a divisor signal, a phase signal and a circulation signal; a frequency divider, configured to receive the input signal and perform an integer division to the input signal according to the divisor signal, so as to generate a frequency division signal; a circulating delay circuit, coupled to the frequency divider and configured to perform at least one circulating operation to the frequency division signal, and for each circulating operation, generate at least one phase delay signal; a first multiplexer, coupled to the circulating delay circuit and configured to select one signal from the frequency division signal and the at least one phase delay signal according to the phase signal, so as to generate a multiplexed signal; and a retimer, coupled to the first multiplexer and configured to generate an output signal.

A frequency generator, includes a control unit, configured to receive an input signal to generate a divisor signal, a phase signal and a circulation signal; a frequency divider, configured to receive the input signal and perform an integer division to the input signal according to the divisor signal, so as to generate a frequency division signal; a circulating delay circuit, coupled to the frequency divider and configured to perform at least one circulating operation to the frequency division signal, and for each circulating operation, generate at least one phase delay signal; a first multiplexer, coupled to the circulating delay circuit and configured to select one signal from the frequency division signal and the at least one phase delay signal according to the phase signal, so as to generate a multiplexed signal; and a retimer, coupled to the first multiplexer and configured to generate an output signal.

A phase-locked loop (PLL) has an oscillator, a counter and a register to sample the oscillator phase as an integer number. A phase predictor uses a fractional-N frequency control word (FCW) to calculate a predicted phase as an integer number. The integer difference between the sampled phase and the predicted phase is used as loop filter input, to generate an oscillator control signal that adjusts the oscillator frequency. The phase predictor may provide noise shaping, for example via a MASH modulator. A first sleep mode control signal blocks a reference clock and feedback of the oscillator clock to the counter. It may also freeze loop filter parameters and block the output clock. A second sleep mode control signal may stop the oscillator.

A phase-locked loop (PLL) has an oscillator, a counter and a register to sample the oscillator phase as an integer number. A phase predictor uses a fractional-N frequency control word (FCW) to calculate a predicted phase as an integer number. The integer difference between the sampled phase and the predicted phase is used as loop filter input, to generate an oscillator control signal that adjusts the oscillator frequency. The phase predictor may provide noise shaping, for example via a MASH modulator. A first sleep mode control signal blocks a reference clock and feedback of the oscillator clock to the counter. It may also freeze loop filter parameters and block the output clock. A second sleep mode control signal may stop the oscillator.

An adaptive voltage converter adapted to compensate for the exponential sensitivities of sub-threshold and near-threshold circuits. The converter can change its power/performance characteristics between different energy modes. The converter may comprise two or more voltage converters/regulators. A multiplexing circuit selects between the outputs of the several converters/regulators depending on the state of a control signal generated by a control facility. The converter is specially adapted to change the output of each converter/regulator based on a number of variables, including, for example, process corner, temperature and input voltage.

An adaptive voltage converter adapted to compensate for the exponential sensitivities of sub-threshold and near-threshold circuits. The converter can change its power/performance characteristics between different energy modes. The converter may comprise two or more voltage converters/regulators. A multiplexing circuit selects between the outputs of the several converters/regulators depending on the state of a control signal generated by a control facility. The converter is specially adapted to change the output of each converter/regulator based on a number of variables, including, for example, process corner, temperature and input voltage.

An injection locked frequency divider includes a mixer circuit and a filter circuit. The mixer circuit includes two mixer units and two inductors. The mixer units mix a differential input voltage signal with a reference signal to output a differential current signal. The inductors cooperatively receive the differential current signal from the mixer units. The filter circuit is connected to the inductors, and filters the differential current signal to output a filtered differential voltage signal.

An injection locked frequency divider includes a mixer circuit and a filter circuit. The mixer circuit includes two mixer units and two inductors. The mixer units mix a differential input voltage signal with a reference signal to output a differential current signal. The inductors cooperatively receive the differential current signal from the mixer units. The filter circuit is connected to the inductors, and filters the differential current signal to output a filtered differential voltage signal.

An adaptive voltage converter adapted to compensate for the exponential sensitivities of sub-threshold and near-threshold circuits. The converter can change its power/performance characteristics between different energy modes. The converter may comprise two or more voltage converters/regulators. A multiplexing circuit selects between the outputs of the several converters/regulators depending on the state of a control signal generated by a control facility. The converter is specially adapted to change the output of each converter/regulator based on a number of variables, including, for example, process corner, temperature and input voltage.

An adaptive voltage converter adapted to compensate for the exponential sensitivities of sub-threshold and near-threshold circuits. The converter can change its power/performance characteristics between different energy modes. The converter may comprise two or more voltage converters/regulators. A multiplexing circuit selects between the outputs of the several converters/regulators depending on the state of a control signal generated by a control facility. The converter is specially adapted to change the output of each converter/regulator based on a number of variables, including, for example, process corner, temperature and input voltage.