Short-circuit protection device for multi-path output power supply

Abstract

The invention relates to the technical field of power supply protection, and discloses a short-circuit protection device for a multi-path output power supply, which comprises a device box, the front surface of the device box is in threaded connection with a box cover, a short-circuit protection circuit is arranged in the device box, and the short-circuit protection circuit is respectively provided with an input terminal and an output terminal on the upper side and the lower side of the device box. The short-circuit protection circuit comprises a control circuit and a reaction circuit, and the reaction circuit comprises a Hall sensor, an input direct-current power source, an auxiliary power supply, a switching tube, a comparator, a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor, a capacitor, a first diode and a second diode. The Hall current sensor serves as a core identification part of a short-circuit fault, converts the primary side current change of a power loop into a voltage signal, and compares the voltage signal with a set reference voltage to judge whether the short-circuit fault exists or not.

Description

technical field [0001] The invention relates to the technical field of power supply protection, in particular to a short-circuit protection device for multiple output power supplies. Background technique [0002] When the load current of the electronic circuit is transient, in order to avoid the overload output including the short circuit of each output terminal and the damage to the power supply circuit itself and the circuit system, the current sampling method of series resistance sampling and series inductance sampling is usually used. , reduce the current through the loop regulation, so as to realize the current limiting protection of the power supply. [0003] The use of resistance detection current is a lossy detection technology, because the resistance loss is I2R watts, although reducing the resistance value can reduce the loss, but after reducing to a certain value, the switching noise begins to superimpose on the relatively small detection signal, causing the detec...

AI Technical Summary

Problems solved by technology

[0003] The use of resistance to detect current is a lossy detection technology, because the resistance loss is I2R watts, although reducing the resistance value can reduce the loss, but after reducing to a certain value, the switching noise begins to superimpose on the relatively small detection signal, causing the detection signal to appear Distortion problem, limited protection, and the use of inductance to detect current is to use the peak threshold of the inductance current in the overcurrent state as the judgment condition for the circuit to work in the short circuit state, but for the power supply with multiple outputs, it is necessary to sample every One signal, the circuit design is complicated, the number of components increases, and it needs to occupy a large area

Images