Negative voltage detection apparatus

Abstract

Disclosed in the invention is a negative voltage detection apparatus. The apparatus is characterized in that a sampling circuit is electrically connected to a positive voltage ground terminal and a negative voltage ground terminal; and thus a voltage drop is generated based on a voltage difference of the two ground terminals and a sampling current is generated. A current transformer is electrically connected to the sampling circuit and a negative pressure reference node, so that the sampling current is outputted relatively and conveniently when the voltage drop is generated. A first voltage-dividing sampling resistor is electrically connected to a positive voltage reference node and a connecting node and a second voltage-dividing sampling resistor is electrically connected to the negative voltage reference node and the connecting node; and the resistance values of the first voltage-dividing sampling resistor and the second voltage-dividing sampling resistor are equal. When the sampling current outputted by the current transformer passes through the second voltage-dividing sampling resistor and then a negative sensing voltage is generated at the connecting node. Therefore, the precise negative sensing voltage can be detected effectively and the negative sensing current or power of the voltage can be obtained.

Description

Technical field [0001] The invention relates to a voltage detection device, in particular to a negative voltage detection device applied to a multi-group power supply system. Background technique [0002] In order to further enhance the safety and reliability of electronic circuit systems, a voltage detection circuit is usually designed in the system, and it usually has an over-voltage or low-voltage detection function to prevent damage caused by the power supply voltage exceeding the working voltage. Or to avoid component breakdown caused by temporary supply voltage drop or overvoltage. However, most voltage detection circuits detect positive voltage, whether it is a low voltage or an over voltage. [0003] On the other hand, in general, research, design, development, and production applications require equipment that can supply current to connect to devices under development or testing. These applications must also monitor the voltage and current consumed by the device to deter...

AI Technical Summary

Problems solved by technology

However, at present, it is generally only possible to easily obtain positive voltage and positive current for detection, and a slight negative current is usually ignored directly; or the negative current can only be measured through an AC signal, so that the required negative current can be obtained using a square wave. current, but such a negative current obtained using a square wave is quite inaccurate

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