Switching circuit for power supply switch

Abstract

The invention discloses a power-switch switching circuit, which comprises a field effect transistor and a control circuit, wherein, the field effect transistor is used for switching on or switching off under the control of a stepping control voltage, and comprises a grid electrode, a source electrode and a drain electrode; the grid electrode is connected with the stepping control voltage, the drain electrode is connected with an input terminal of a power supply, and the source electrode is connected with an output terminal of a load; the control circuit is used for synthesizing two control voltages which are input by the input terminal of the control circuit to form and output the stepping control voltage through the control of a logic control signal; the control circuit is connected with the grid electrode of the field effect transistor. In the power-switch switching circuit, the stepping control voltage is used for charging the grid electrode of the field effect transistor, surge current which is generated when the field effect transistor is conducted can be restrained through the control of the stepping control voltage, so the circuit works stably under the control of a power-switch, and devices are not easy to be damaged; in addition, because the circuit adopts one field effect transistor only, the cost is low and the volume is small.

Description

technical field [0001] The invention relates to a power switch control technology, in particular to a power switch switching circuit, which belongs to the field of electrical technology. Background technique [0002] In short, a switch circuit is a circuit that controls the on-off of a circuit, usually used to control the on-off of a power supply path, and the on-off of the switch is determined by the high or low level of the control signal. The closing speed of the switches on the switching circuit is usually determined by the switch control circuit. in addition, figure 1 It is a structural schematic diagram of a switch switching circuit in the prior art, such as figure 1 In the switch switching circuit shown, in order to ensure the power supply stability of the output circuit, there are usually a large number of energy storage capacitors on the output side of the power supply. In the figure, CL is the equivalent capacitance of the load circuit, which is usually thousand...

AI Technical Summary

Problems solved by technology

It can be seen that this method requires two sets of high-power MOSFET devices, the circuit cost is relatively expensive, and two control signals are required, which wastes the I / O port resources of the controller. In addition, the device volume of the two sets of high-power MOSFETs is also relatively large. Big, not easy to miniaturize

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