Switch detection method

Abstract

The invention provides a switch detection method, including making the control chip MCU output the voltage value of the conduction MOS transistor Q1, and obtaining the current value flowing through the MOS transistor Q1 in the switch detection circuit connected to the control chip MCU; When the first control command of the preset threshold value is used, the control chip MCU is made to output the voltage value of closing the MOS transistor Q1, and the sampling voltage value at the AD sampling terminal in the switch detection circuit is obtained after the MOS transistor Q1 is disconnected; if the sampling voltage value is greater than the standard If the sampled voltage value is zero, then it is determined that the switch SW is in a closed state; if the sampled voltage value is zero, it is determined that the switch SW is open. According to the external switch SW in different states to detect the sampling voltage value of the MOS transistor Q1 in the on and off state, and refer to the change of the current flowing through Q1 in different states of the reference SW, which leads to the change of the sampling voltage value to complete the state of the switch SW Compared with the prior art, the detection of the switch state can be completed without using expensive electrical components, which reduces the cost of the manufacturer.

Description

technical field [0001] The invention belongs to the field of circuit detection, in particular to a switch detection method. Background technique [0002] In the prior art, in the process of detecting the switch state, the detection accuracy is often improved by adding multiple resistors in the circuit to increase the resistance voltage division. However, this type of resistor is an alloy resistor, which is large in size and high in cost. It is not conducive to reducing the cost of products. Another way is to lead out multiple wires at the switch SW, so as to make the electrical parameters in the detection circuit change according to the different states of the switch to complete the detection, but the cost of this type of switch is very high, which is not conducive to reducing product cost. Increased manufacturing pressure on manufacturers. Contents of the invention [0003] In order to solve the shortcomings and deficiencies in the prior art, the invention provides a sw...

AI Technical Summary

Problems solved by technology

[0002] In the prior art, in the process of detecting the switch state, the detection accuracy is often improved by adding multiple resistors in the circuit to increase the resistance voltage division. However, this type of resistor is an alloy resistor, which is large in size and high in cost. Not conducive to compressing the cost of products

Another way is to lead out multiple wires at the switch SW, so as to make the electrical parameters in the detection circuit change according to the different states of the switch to complete the detection, but the cost of this type of switch is very high, which is not conducive to reducing product costs. Increased manufacturing pressure on manufacturers

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