Load open circuit detection circuit and method for high-side switch

Abstract

The invention discloses a load open circuit detection circuit and method for a high-side switch. The circuit includes a voltage comparator, a voltage acquisition circuit, a current source, a detection resistor and a threshold setting circuit; the current source is connected in parallel with two ends of a high-side switch to be tested; the high-side switch to be tested is connected in series with a load; the detection resistor is commonly connected with the current source and the high-side switch to be tested; the connecting point of the detection resistor, the current source and the high-side switch to be tested is connected with the input end of the voltage acquisition circuit; the output end of the voltage acquisition circuit is connected with the reverse input end of the voltage comparator; the threshold setting circuit is connected with the forward input end of the voltage comparator; and the output end of the voltage comparator is adopted as the output end of the load open circuit detection circuit and is used for outputting load open circuit fault signals. The load open circuit detection circuit and method can be realized through common discrete semiconductor electronic devices; parameters can be adjusted according to use conditions, so that the load open circuit detection circuit and method can be applicable to different power source voltage; and detection sensitivity can be adjusted. The load open circuit detection circuit and method have the advantages of simplicity, easiness in implementation and bright application prospect.

Description

technical field [0001] The invention relates to the technical field of electric and electronic equipment control, in particular to an open-load detection circuit and method for a high-side switch. Background technique [0002] In many applications of electrical and electronic equipment with high safety requirements, it is necessary to control the on and off of the load through the high-side switch, and at the same time, it is necessary to detect whether the load is disconnected from the control equipment, so that when the load and the control equipment are accidentally disconnected To alarm, so that the control system of electrical and electronic equipment can take corresponding measures to avoid the occurrence of hazards. Therefore, the load open circuit detection controlled by the high side switch is very important. [0003] The open-load detection controlled by the high-side switch mainly depends on the integrated circuit installed in the high-side switch. However, the cu...

AI Technical Summary

Problems solved by technology

[0004] Technical Problems Solved by the Invention The existing high-side switch-controlled open-load detection integrated circuit is only suitable for low-voltage DC applications, and cannot be used in relatively high-voltage situations

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