Self-resetting switching circuit based on feedback control, and control method thereof

Abstract

The invention discloses a self-resetting switching circuit based on feedback control. The switching circuit comprises a PMOS tube, an input optocoupler, an output optocoupler, a self-reset switch anda controller. The source electrode and the grid electrode of the PMOS tube are connected through a first divider resistor and a first current-limiting resistor which are sequentially connected in series; a connection point of the first divider resistor and the first current-limiting resistor is connected to an output end collector of the input optocoupler through the second divider resistor; the input end anode of the input optocoupler is connected with high potential; the input end cathode of the input optocoupler is connected to the controller; the input end anode of the output optocoupler is connected to the output end of a power supply; the self-reset switch is connected between the input end cathode of the output optocoupler and the output end emitter of the input optocoupler in series; the output end collector of the output optocoupler is further connected to the controller; and the output end emitter of the output optocoupler is grounded. The switching circuit can be applied toa large-current environment, the size of the switching circuit can be reduced, surge impact can be reduced during abnormal power on and off, and load equipment can be prevented from being powered on and off non-autonomously.

Description

technical field [0001] The invention relates to a switch control circuit, in particular to a feedback control-based self-resetting switch circuit and a control method. Background technique [0002] In the prior art, most of the common self-locking power switch circuits realize the power off or access through the normally open or normally closed of two contacts. This on-off control method has the following three main disadvantages: [0003] First of all, when the current is too large, the current limiting requirements are considered, resulting in a very large circuit size, which is inconvenient to install and use; secondly, when the power supply has abnormal phenomena such as power outages and trips, power failure will occur. When the circuit is powered on and restored , the self-locking switch in the conduction state will power on the load equipment immediately. At this time, the surge on the power supply line will have a greater adverse effect on the equipment, especially w...

AI Technical Summary

Problems solved by technology

[0003] First of all, when the current is too large, the current limiting requirements are considered, resulting in a very large circuit size, which is inconvenient to install and use; secondly, when the power supply has abnormal phenomena such as power outages and trips, power failure will occur. When the circuit is powered on and restored , the self-locking switch in the conduction state will power on the load equipment immediately. At this time, the surge on the power supply line will have a greater adverse effect on the equipment, especially when the abnormal situation occurs repeatedly, it will make the load equipment frequent Non-autonomous power on and off seriously affects the life of the equipment; in addition, the existing self-locking power switch cannot realize program-controlled shutdown, which is difficult to meet application requirements

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