A Multi-voltage Acquisition and Fault Detection Circuit for Eliminating Floating Voltage

Abstract

The invention relates to a multi-voltage acquisition and fault detection circuit for eliminating floating voltage, including a multi-voltage acquisition circuit and a fault detection circuit, the multi-voltage acquisition circuit includes an isolation diode, a pull-down resistor, a zero-ohm resistor and a differential amplifier circuit, and the fault detection circuit includes Reference power supplies, analog switches, and digital isolators. The circuit of the present invention can reduce the diode leakage current to the microampere level through the pull-down resistor, thereby eliminating the floating voltage caused by the leakage current during the multi-voltage acquisition process. Matching reduces the generation of potential channel leakage, thereby improving the accuracy of voltage sampling and reducing the false alarm rate; through the fault detection circuit, the self-test function of the sampling circuit can be realized, which improves the circuit fault detection rate, thereby improving the product quality. reliability.

Description

technical field [0001] The invention is a multi-voltage acquisition and fault detection circuit for eliminating floating voltage, which belongs to the field of aviation electrical technology. Background technique [0002] In the aircraft power distribution network, when there are multiple input power sources for power distribution products, it is necessary to identify the input voltages from different power sources to analyze the operation of each input power source; if a single power source is powered on, due to the isolation diode in the voltage acquisition circuit The existing leakage current leads to the generation of floating voltage, and there are potential channels in the operational amplifier circuit, which eventually leads to false positives in the sampling of other input voltages, and the product fails to recognize the input voltage. Therefore, there is a need for a circuit that can eliminate the floating voltage generated during the multi-voltage acquisition proce...

AI Technical Summary

Problems solved by technology

[0002] In the aircraft power distribution network, when there are multiple input power sources for power distribution products, it is necessary to identify the input voltages from different power sources to analyze the operation of each input power source; if a single power source is powered on, due to the isolation diode in the voltage acquisition circuit The existing leakage current leads to the generation of floating voltage, and there are potential channels in the operational amplifier circuit, which eventually leads to false positives in the sampling of other input voltages, and the product fails to recognize the input voltage.

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