Slow start circuit suitable for boosting power supply of power supply

Abstract

The invention relates to a slow start circuit suitable for boosting power supply of a power supply. The slow start circuit comprises a load module, a control module, a ripple elimination module, a power supply module, a first switch module and a second switch module; the power supply module is connected with the control module; the first switch module is arranged at the output end of the power supply module and connected with the load module and the ripple elimination module, so that a boosting power supply branch circuit and an absorption branch circuit can be formed; and the first switch module is connected with the control module, so that a first switch branch circuit can be formed; the first switch branch circuit acts at the initial stage of boosting power supply so as to enable the boosting power supply branch circuit and the absorption branch circuit to be synchronously switched on; the second switch module is connected with the control module and the first switch module, so that a second switch branch circuit can be formed; the second switch branch circuit acts after the first switch branch circuit acts for T time so as to cooperate with the first switch branch circuit to jointly control boosting power supply of the power supply module, wherein T is not less than the charging time of the absorption branch circuit. The stability of the slow start circuit is improved.

Description

technical field [0001] The invention relates to the technical field of ammeters, in particular to a slow-start circuit suitable for boosting power supply. Background technique [0002] With the expansion of smart terminals, such as the application market of prepaid electric meters, the demand for CIUs is increasing, and it is becoming more and more common to boost power supplies such as batteries. In order to reduce the back-end ripple, designers usually add An electrolytic capacitor is added at the back end, and how to control the battery to supply power to the boost circuit at a specific time through the chip has become a matter that every designer must consider. [0003] Most of the existing schemes use two triode conversion circuits to supply power to the booster circuit. Because the electrolytic capacitor needs to be charged in the initial stage of power supply boosting, this causes the current of the triode to be too large at the beginning of opening, and the voltage o...

AI Technical Summary

Problems solved by technology

[0003] Most of the existing schemes use two triode conversion circuits to supply power to the booster circuit. Because the electrolytic capacitor needs to be charged in the initial stage of power supply boosting, this will cause the current of the triode to be too large at the beginning of opening, and the voltage of the battery and other power sources will be pulled too low, which will affect the battery. Waiting for the power to supply power to the MCU makes the MCU reset frequently, resulting in circuit instability

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