Optoelectronic isolator with serial communication interface

Abstract

The invention relates to an optoelectronic isolator with a serial communication interface. The optoelectronic isolator comprises a shell, a circuit board, a wiring terminal, an optoelectronic isolation circuit, a DC / DC power isolation circuit, an interface protection circuit, a power protection circuit and an LED indicating lamp, wherein the optoelectronic isolation circuit, the DC / DC power isolation circuit, the interface protection circuit, the power protection circuit, the LED indicating lamp and the wiring terminal are fixed on the circuit board which is fixed in the shell. Compared with the prior art, the invention is particularly used to the applied environments of railroad and subway signal system sites, can effectively isolate intense electromagnetic interference from lightning strike, static, and the like generated by exterior or opponent equipment, conforms to special site requirement of industry and particularly has the advantages of good optoelectronic isolation effect, long performance, good stability, convenient installation and use, and the like.

Description

technical field [0001] The invention relates to a photoelectric isolator, in particular to a serial communication interface photoelectric isolator. Background technique [0002] In railway and subway signaling systems, point-to-point connections between multiple devices are often encountered. At present, the more common point-to-point connection methods include some serial communication interfaces such as RS232, RS422, RS485 and HDLC. When two devices with different voltage differences are connected together, the unstable voltage will form a "ground loop" and cause a huge current between multiple serial devices, causing damage to the device. For example, in the railway signal machinery room earlier, the point-to-point interconnection between equipment (such as between two industrial computers), sometimes using RS232 serial interface, often caused the RS232 interface to burn out, and sometimes caused the internal circuit board of the machine to be damaged. damage. [0003] ...

AI Technical Summary

Problems solved by technology

When there is a lightning strike, it is easy for lightning interference to be transmitted to the wireless train number device through the antenna, and then transmitted to the station extension through the RS422 connection line, resulting in damage to the circuit board of the station extension

Due to the lack of sufficient understanding of this lightning hazard at the beginning, the station extensions were seriously damaged

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