Abstract: An apparatus includes a first circuit, a second circuit and a third circuit. The first circuit may be configured to generate a first code by counting a number of cycles of an input clock signal during a period. The period may be determined by an output clock signal and a second code. The second circuit may be configured to generate a third code by a delta-sigma modulation of the first code. The third circuit may be configured to generate the output clock signal in response to the third code. An accuracy of a frequency of the output clock signal may be determined by a current value of the second code.

Abstract: An apparatus includes a first circuit, a second circuit and a third circuit. The first circuit may be configured to generate a first code by counting a number of cycles of an input clock signal during a period. The period may be determined by an output clock signal and a second code. The second circuit may be configured to generate a third code by a delta-sigma modulation of the first code. The third circuit may be configured to generate the output clock signal in response to the third code. An accuracy of a frequency of the output clock signal may be determined by a current value of the second code.

Abstract: An apparatus includes a first circuit, a second circuit and a third circuit. The first circuit may be configured to generate a first code by counting a number of cycles of an input clock signal in a period determined by (i) an output clock signal and (ii) a second code. The second code may be variable. The second circuit may be configured to generate a third code by a delta-sigma modulation of the first code. The third circuit may be configured to generate the output clock signal (i) in response to the third code and (ii) within an accuracy determined the second code.

Abstract: An apparatus includes a first circuit, a second circuit and a third circuit. The first circuit may be configured to generate a first code by counting a number of cycles of an input clock signal in a period determined by (i) an output clock signal and (ii) a second code. The second code may be variable. The second circuit may be configured to generate a third code by a delta-sigma modulation of the first code. The third circuit may be configured to generate the output clock signal (i) in response to the third code and (ii) within an accuracy determined the second code.

Abstract: A timing device that includes an OTP NVM, a first periodic signal generator operable to generate a periodic signal having a first frequency, a second periodic signal generator operable to generate a periodic signal having a frequency that is lower than the first frequency, and selection logic. In a first operating mode, the selection logic is configured to output the first periodic signal at an output terminal as long as a crystal clock feedback signal is received at the input terminal and output the second periodic signal when the crystal clock feedback signal is not received at the input terminal. In a second operating mode, the selection logic is configured to output the first periodic signal as long as a output enable signal is received at the input terminal and not provide any output at the output terminal when the output enable signal is not received at the input terminal.