A Precise Timing Circuit Triggered by Wide Supply Voltage

Abstract

The invention comprises a triggerable accurate timing circuit with a wide supply voltage range. The accurate timing circuit comprises a first comparator, a second comparator, a timer and a counter, wherein the first comparator, the second comparator, the timer and the counter are connected with a power supply; the input ends of the first and second comparators are connected with a trigger control circuit, the output end of the first comparator is connected with the reset end of the timer, the output end of the second comparator is connected with the reset end of the counter, and the second comparator is connected with a regenerative feedback circuit; the timer is connected with a multi-resonance circuit for changing the period of multi-resonance square waves; and the counter is connected with a frequency-division timing circuit, the output end of the timer is connected with the counter, and the output end of the counter is connected with the trigger control circuit. The accurate timing circuit provided by the invention is simple in structure, high in timing precision in severe environmental condition as high / low-temperature and the like, adaptive to wide supply voltage range and capable of being triggered repeatedly.

Description

technical field [0001] The invention belongs to the technical field of timing circuits, and relates to a precise timing circuit that can be triggered by a wide power supply voltage. Background technique [0002] Most of the existing timing circuits adopt the following three forms. First, a timing circuit based on a digital circuit. This kind of circuit takes the digital signal processing circuit as the core, uses the high-precision clock signal provided by the crystal oscillator and other components to the digital signal processing chip, and realizes the triggering precise timing function through the digital signal processing circuit. Limitations in the application of this circuit: In order to ensure the normal operation of the crystal oscillator and digital signal processing chip, the circuit must be provided with a power supply with higher precision requirements. Therefore, the structure of this circuit is relatively complicated, and it cannot adapt to a wide supply volt...

AI Technical Summary

Problems solved by technology

Limitations in the application of this circuit: In order to ensure the normal operation of the crystal oscillator and digital signal processing chip, it is necessary to provide a power supply with higher precision requirements for the circuit

Limitations in the application of this circuit: When applied to minute-level timing, the timing capacitor has a large capacity (several microfats to tens of microfats), and the high and low temperature leakage current and capacity of the timing capacitor vary greatly, resulting in a change in timing duration of more than 50%. , so the timing accuracy of the circuit is poor in high and low temperature environments

Limitations in the application of this circuit: the timing starts after the first power-on, and the power is automatically turned off after the timing ends, and the timing cannot be triggered again

Therefore, this timing circuit does not have the function of repeatedly triggerable timing, and cannot meet the needs of multiple triggerable timing.

Images