Power supply input clamping circuit and chip

Abstract

The invention provides a power supply input clamping circuit and a chip. A power supply module comprises a first power supply and a second power supply. A clamping module clamps a first voltage provided by the first power supply and a second voltage provided by the second power supply, and supplies a clamping output voltage after clamping to a high-voltage isolation module. The high-voltage isolation module performs high-voltage isolation on the first voltage and the second voltage based on the clamping output voltage. A potential selection module compares a first isolation voltage with a second isolation voltage after high-voltage isolation to determine an output voltage of an output end. According to the invention, clamping output is performed on multiple power supplies, high-voltage isolation is performed on the voltages of the multiple power supplies, and electronic devices in contact with high voltage in the circuit are reduced, so that low-voltage line electronic components are prevented from being influenced by the high-voltage power supplies, and the service life of the electronic components is prolonged. Compared with the prior art, an anti-backflow device does not need tobe additionally arranged to avoid series connection between a high-voltage power supply and a low-voltage power supply, and the cost of the whole power supply circuit is reduced.

Description

technical field [0001] The invention relates to the technical field of integrated circuits, in particular to a power supply input clamping circuit and a chip including the power supply input clamping circuit. Background technique [0002] With the continuous development of industrial and agricultural production, users have higher and higher requirements for power supply reliability. In the existing power supply system, there are often two or even multiple power supply applications. In the case of multiple power supplies, the power system usually selects the power supply with the highest voltage and the best power supply reliability from the multiple power supplies as the power supply. In order to screen out the optimal power supply from multiple power supplies, it is necessary to set a power supply input clamping circuit in the power supply system. [0003] At present, the existing power supply input clamping circuit generally utilizes two low dropout regulator (LDO) units...

AI Technical Summary

Problems solved by technology

However, when the existing power supply input clamping circuit uses two LDO units, an anti-backflow device needs to be added at the same time to avoid collusion between the high-voltage power supply and the low-voltage power supply, thereby increasing a lot of cost

In addition, affected by the high-voltage power supply, the LDO unit and the power selection circuit will accelerate the aging of their own electronic components due to high voltage, thereby increasing the update speed of electronic components, which also increases a lot of costs

Images