A circuit includes a counter circuit, a logic circuit, and a clock divider. The counter circuit includes a clock divider counter to be loaded with most significant bits of a divider value, and decremented at a same edge of each pulse of a clock signal. The logic circuit compares a value contained in the divider counter to a reference value and generates an end count signal as a function of the value contained in the divider counter matching the reference value, and transitions a toggle signal at a same edge of each pulse of the end count signal. The clock divider counter is reloaded with the most significant bits of the divider value as a function of the end count signal. The clock divider generates a divided version of the clock signal as a function of the toggle signal.

A method includes loading a clock divider counter with most significant bits (MSBs) of a divider value, decrementing the counter at a same edge of each pulse of a clock signal, and comparing a value contained in the counter to a reference value and generating an end count signal if the value contained in the counter matches the reference value. If the value is even, the reference value is set to 1. If the value is odd, the reference value is set to 1, except for every other assertion of the end count signal, where the reference value is instead set to 0. A toggle signal transitions at a same edge of each pulse of the end count signal. The counter is reloaded with MSBs of the divider value based upon the end count signal. A divided version of the clock signal is generated based upon the toggle signal.

A method includes loading a clock divider counter with most significant bits (MSBs) of a divider value, decrementing the counter at a same edge of each pulse of a clock signal, and comparing a value contained in the counter to a reference value and generating an end count signal if the value contained in the counter matches the reference value. If the value is even, the reference value is set to 1. If the value is odd, the reference value is set to 1, except for every other assertion of the end count signal, where the reference value is instead set to 0. A toggle signal transitions at a same edge of each pulse of the end count signal. The counter is reloaded with MSBs of the divider value based upon the end count signal. A divided version of the clock signal is generated based upon the toggle signal.

A circuit includes a counter circuit, a logic circuit, and a clock divider. The counter circuit includes a clock divider counter to be loaded with most significant bits of a divider value, and decremented at a same edge of each pulse of a clock signal. The logic circuit compares a value contained in the divider counter to a reference value and generates an end count signal as a function of the value contained in the divider counter matching the reference value, and transitions a toggle signal at a same edge of each pulse of the end count signal. The clock divider counter is reloaded with the most significant bits of the divider value as a function of the end count signal. The clock divider generates a divided version of the clock signal as a function of the toggle signal.

A circuit includes a counter circuit, a logic circuit, and a clock divider. The counter circuit includes a clock divider counter to be loaded with most significant bits of a divider value, and decremented at a same edge of each pulse of a clock signal. The logic circuit compares a value contained in the divider counter to a reference value and generates an end count signal as a function of the value contained in the divider counter matching the reference value, and transitions a toggle signal at a same edge of each pulse of the end count signal. The clock divider counter is reloaded with the most significant bits of the divider value as a function of the end count signal. The clock divider generates a divided version of the clock signal as a function of the toggle signal.

A circuit includes a counter circuit, a logic circuit, and a clock divider. The counter circuit includes a clock divider counter to be loaded with most significant bits of a divider value, and decremented at a same edge of each pulse of a clock signal. The logic circuit compares a value contained in the divider counter to a reference value and generates an end count signal as a function of the value contained in the divider counter matching the reference value, and transitions a toggle signal at a same edge of each pulse of the end count signal. The clock divider counter is reloaded with the most significant bits of the divider value as a function of the end count signal. The clock divider generates a divided version of the clock signal as a function of the toggle signal.

Embodiments relate to an accumulator-based phase memory. An aspect includes a phase correction calculator configured to, based on receipt of a new frequency tuning word on a frequency tuning word input, determine a phase difference between the new frequency tuning word and a current frequency tuning word, and determine a product of the phase difference and a value of a counter. Another aspect includes wherein the accumulator-based phase memory determines a phase offset value based on the product of the phase difference and the value of the counter. Another aspect includes the accumulator-based phase memory further comprising a waveform generator configured to generate a waveform based on the new frequency tuning word and the phase offset value.

A digital control oscillator circuit includes: a ring oscillator having delay elements delaying a pulse signal; a counter circuit counting the circulation number of the pulse signal; a rough period generation unit acquiring a period setting value as a magnification ratio for a reference clock, and counting the reference clock using an integer part of the ratio to generate a rough period timing; a fraction conversion unit converting a decimal point part of the ratio into the number of the elements passed by the pulse signal to generate a fraction; and an output processing unit selecting a timing when outputs of the ring oscillator and the counter circuit become values corresponding to the fraction as an output timing when a time corresponding to the fraction has passed after the rough period timing, and generating an output signal oscillating at a period represented by the period setting value according to the output timing.

A digital control oscillator circuit includes: a ring oscillator having delay elements delaying a pulse signal; a counter circuit counting the circulation number of the pulse signal; a rough period generation unit acquiring a period setting value as a magnification ratio for a reference clock, and counting the reference clock using an integer part of the ratio to generate a rough period timing; a fraction conversion unit converting a decimal point part of the ratio into the number of the elements passed by the pulse signal to generate a fraction; and an output processing unit selecting a timing when outputs of the ring oscillator and the counter circuit become values corresponding to the fraction as an output timing when a time corresponding to the fraction has passed after the rough period timing, and generating an output signal oscillating at a period represented by the period setting value according to the output timing.