An electronic circuit includes a first oscillator, a second oscillator and ancillary circuitry. The first oscillator is configured to generate a first clock signal and has a first wake-up delay. The second oscillator is configured to generate a second clock signal and has a second wake-up delay that is shorter than the first wake-up delay. The ancillary circuitry is configured to provide the second clock signal as an output clock signal during wake-up of the first oscillator, and, following the first wake-up delay, to provide the first clock signal as the output clock signal.

Apparatuses for performing combination logic operations with an combination logic circuit are disclosed. According to one embodiment, the apparatus comprises a first-in-first-out stage comprising an combination logic circuit, a input ring counter circuit coupled to the first-in-first-out stage and configured to selectively provide a push signal to the first-in-first-out stage, and a output ring counter circuit coupled to the first-in-first-out stage and configured to selectively provide a pop signal to the first-in-first-out stage, wherein the first-in-first-out stage is configured to perform calculations on input data with the combination logic circuit to generate output data responsive to receiving the push signal and to provide the output data based on the calculations responsive to receiving the pop signal.

Apparatuses for performing combination logic operations with an combination logic circuit are disclosed. According to one embodiment, the apparatus comprises a first-in-first-out stage comprising an combination logic circuit, a input ring counter circuit coupled to the first-in-first-out stage and configured to selectively provide a push signal to the first-in-first-out stage, and a output ring counter circuit coupled to the first-in-first-out stage and configured to selectively provide a pop signal to the first-in-first-out stage, wherein the first-in-first-out stage is configured to perform calculations on input data with the combination logic circuit to generate output data responsive to receiving the push signal and to provide the output data based on the calculations responsive to receiving the pop signal.

A frequency measurement apparatus includes: a measurement period setting circuit that sets a measurement period based on a reference clock signal; a first counter circuit that counts the number of pulses of the reference clock signal in a period based on an input signal during the measurement period; a second counter circuit that counts the number of pulses of the input signal during the measurement period; a first frequency calculation circuit that calculates a first frequency; a second frequency calculation circuit that calculates a second frequency; and a frequency selection circuit that selects the first frequency or the second frequency as a frequency of the input signal.

Disclosed examples include non-volatile counter systems to generate and store a counter value according to a sensor pulse signal, and power circuits to generate first and second supply voltage signals to power first and second power domain circuits using power from the sensor pulse signal, including a switch connected between first and second power domain supply nodes, a boost circuit, and a control circuit to selectively cause the switch to disconnect the first and second power domain circuits from one another after the first supply voltage signal rises above a threshold voltage in a given pulse of the sensor pulse signal, and to cause the boost circuit to boost the second supply voltage signal after the regulator output is disconnected from the second power domain supply node in the given pulse.

In described examples, a counter system includes a counter, a parity detector, a toggle flop, and a comparator. The counter iterates a count through a set of binary states in response to a clock signal, so that a binary value of a single bit of the count changes at each iteration. The parity detector detects the parity of the count. The toggle flop output is coupled to the toggle flop input. The toggle flop outputs a binary flop value. The binary flop value toggles between zero and one in response to the toggle flop input and the clock signal. The comparator compares the parity of the count and the toggle flop output, and outputs a first comparator value if the parity of the count and the toggle flop output are the same, and a second comparator value if the parity of the count and the toggle flop output are different.

In described examples, a counter system includes a counter, a parity detector, a toggle flop, and a comparator. The counter iterates a count through a set of binary states in response to a clock signal, so that a binary value of a single bit of the count changes at each iteration. The parity detector detects the parity of the count. The toggle flop output is coupled to the toggle flop input. The toggle flop outputs a binary flop value. The binary flop value toggles between zero and one in response to the toggle flop input and the clock signal. The comparator compares the parity of the count and the toggle flop output, and outputs a first comparator value if the parity of the count and the toggle flop output are the same, and a second comparator value if the parity of the count and the toggle flop output are different.

A circuit, for generating ultrahigh-precision digital pulse signals, comprises: a pulse edge control circuit used for delaying a signal on an input pin and accurately controlling positions of a rising edge and a falling edge of the pulse signal to accurately control the width of pulses and generate ultrahigh-precision pulses; a static calibration circuit used for calculating step size information representing the relationship between a work clock period of a system and a delay of delay cells in the pulse edge control circuit when the system is powered on to work, and storing the step size information, wherein the step size information is the number of delay cells through which the signal is propagated and passes within one system clock period; and a dynamic calibration circuit used for dynamically calculating step size information when a rising edge or a falling edge of each pulse in the input pin arrives.

Aspects of the disclosure are directed to reducing clock-ungating induced voltage droop by determining a maximum frequency value associated with an output clock waveform; modulating a clock frequency of the output clock waveform for a first time duration based on a first programmable mask pattern or a first Boolean function; and determining if either the first programmable mask pattern or the first Boolean function should be changed. In accordance with one aspect, a voltage droop mitigation circuit includes a control logic for receiving an input clock waveform and a clock enable signal waveform and for outputting a gated clock enable signal waveform; a latch coupled to the control logic, the latch for holding a state of the gated clock enable signal waveform and a AND gate coupled to the latch, the AND gate for outputting an output clock waveform.

A frequency measurement apparatus includes: a measurement period setting circuit that sets a measurement period based on a reference clock signal; a first counter circuit that counts the number of pulses of the reference clock signal in a period based on an input signal during the measurement period; a second counter circuit that counts the number of pulses of the input signal during the measurement period; a first frequency calculation circuit that calculates a first frequency; a second frequency calculation circuit that calculates a second frequency; and a frequency selection circuit that selects the first frequency or the second frequency as a frequency of the input signal.