Fault Diagnosis Circuit Based on SCM AD Converter

Abstract

The invention relates to a fault diagnosis circuit based on an AD (analog-to-digital) convertor of a single chip microcomputer, which comprises a single chip microcomputer and a resistance network, wherein the resistance network comprises a plurality of branch resistance networks, each branch resistance network is provided with a divider resistor and a biasing resistor, one end of the biasing resistor is grounded, and the other end is connected with an input end of the AD convertor of the single chip microcomputer; and different fault signals are respectively input to input ends of the branch resistance networks, and output ends of the branch resistance networks are all connected with the input end of the AD convertor of the single chip microcomputer. Because the resistance values of the divider resistors are different, the output voltage values are different when the fault signals are different. Therefore, the fault diagnosis circuit can distinguish which path or how many paths has / have faults according to the setting of internal programs of the single chip microcomputer, and thereby, the fault diagnosis circuit can realize the real-time monitoring on a plurality of fault signals by a port of the AD convertor, realize the sufficient utilization of the AD convertor, and save I / O ports of the single chip microcomputer.

Description

technical field [0001] The invention relates to a diagnosis circuit, in particular to a fault diagnosis circuit based on a single-chip AD converter for fault diagnosis. Background technique [0002] SCM-based industrial, military equipment, and instrumentation need fault diagnosis. The common diagnosis method is to use the I / O port of the SCM to read the fault status. If there are many but not enough I / O ports, it is usually realized by expanding the ports, and the cost is relatively high. Contents of the invention [0003] Aiming at the problem that the I / O port of the single-chip microcomputer is limited and the AD converter in the chip is not fully utilized, the invention provides a fault diagnosis circuit which makes full use of the AD converter of the single-chip microcomputer to realize fault detection by using the AD converter port of the single-chip microcomputer. [0004] In order to achieve the above object, the technical scheme adopted in the present invention ...

AI Technical Summary

Problems solved by technology

[0002] SCM-based industrial, military equipment, and instrumentation need fault diagnosis. The common diagnosis method is to use the I / O port of the SCM to read the fault status. In the case of many but not enough I / O ports, it is usually realized through external expansion ports, and the cost is relatively high

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