Method for realizing RTC high precision based on temperature sensor

Abstract

The invention provides a method for realizing RTC high precision based on a temperature sensor, and the method comprises the following specific steps: enabling target equipment to be connected with a GPS module, and putting the target equipment and the GPS module into a constant-temperature box; enabling the target equipment RTC and the GPS clock signal to be synchronously output; calibrating the clock error of the RTC, and calculating the PPM value of the RTC crystal oscillator of the target equipment at the constant temperature of the constant temperature box; determining the type of an RTC clock crystal oscillator of the target equipment; determining related parameters and a frequency temperature curve of the RTC clock crystal oscillator, and calculating the frequency change of the crystal by utilizing a formula; collecting and transmitting the environment temperature to the target equipment, and when the environment temperature change exceeds 2 DEG C, enabling a self-calibration program in the target equipment to recalculate the PPM value of the RTC of the target equipment; calculating a new calibration value according to the corresponding relationship between the PPM error value and the RTC calibration function; and calibrating the RTC clock crystal oscillator by using the latest calibration value. Temperature compensation of the crystal oscillator can be adaptively realized according to the temperature so that power consumption can be reduced and precision of the equipment clock can be enhanced.

Description

technical field [0001] The invention relates to the technical field of realizing self-calibration and time synchronization of an RTC clock of a terminal device, in particular to a method for realizing RTC high precision based on a temperature sensor. Background technique [0002] RTC is the abbreviation of real-time clock, real-time clock chip is one of the most widely used consumer electronic products in daily life. It provides accurate real-time time for people, or provides accurate time reference for electronic systems. At present, most real-time clock chips use crystal oscillators with high precision as clock sources. [0003] For a real-time clock, the stability of the crystal oscillation frequency directly affects the accuracy of the real-time clock. The parameters used to describe the frequency characteristics of a crystal mainly include frequency tolerance, frequency temperature characteristics and frequency voltage characteristics. They describe the change of cryst...

AI Technical Summary

Problems solved by technology

However, based on the consideration of device power consumption, cost or installation geographical environment, some devices do not have network modules and GPS modules. After the device has not been synchronized with the clock for a long time, the device time will deviate greatly from the actual time.