A wide temperature range low temperature drift timing system and its timing method

Abstract

The present invention relates to a wide temperature range low temperature drift timing system and its timing method, comprising a square wave generating circuit, a timing circuit and an arithmetic circuit, the square wave generating circuit includes an oscillator N1 and a frequency divider N2, the oscillator N1 The input terminals of the frequency divider N2 are connected to the power supply through the resistor R1 and grounded through the capacitor C1, the output terminal of the oscillator N1 is connected to the input terminal of the frequency divider N2, and the output terminal of the frequency divider N2 and the output terminal of the timing circuit are connected to the operational amplifier. connected to the input of the circuit. The present invention can realize working temperature T C =-55~125℃, the effect of the timing duration changing with the temperature does not exceed 1%.

Description

technical field [0001] The invention relates to a timing circuit, in particular to a wide temperature range low-temperature drift timing system and a timing method thereof. Background technique [0002] At present, the timing function of electronic circuits is mainly realized by using a timer chip and its external timing capacitor and resistor to form a single inversion signal generating circuit. The temperature characteristics of the circuit are determined by the temperature characteristics of the timing capacitor and resistor. When the output signal of the circuit lasts for a long time (≥10s) before inverting, only capacitors made of materials such as second-class ceramics or tantalum can be used, and their capacitance is at the operating temperature T of the circuit. C = The drift in the range of -55 ~ 125 ℃ is more than 15%, which causes a corresponding error in the duration of the timing signal output by the circuit, and cannot achieve the purpose of precise timing in t...

AI Technical Summary

Problems solved by technology

When the output signal of the circuit lasts for a long time (≥10s) before inverting, only capacitors made of materials such as second-class ceramics or tantalum can be used, and their capacitance value is within the operating temperature T of the circuit. C = The drift in the range of -55 ~ 125 ℃ is more than 15%, resulting in a corresponding error in the duration of the timing signal output by the circuit, which cannot achieve the purpose of precise timing in the full working temperature range

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