摘要
基于工程应用需要,研发了一款具备良好电气隔离性能的USB-485转换模块。模块以FT232BM作为核心,结合MAX1487实现USB与RS485间的信号电平转换,同时两者间以HCPL600光耦进行隔离。电源部分以脉冲变压器作为前向通路隔离元件;以MC33063构建开关电源作为变压器原边输入;以PC817光耦作为反馈通路隔离元件;以KA431构建稳压电路,从而通过反馈通路调节开关电源输出,确保隔离电源输出稳定。经测试模块整体性能良好,可投入实际使用。
For engineering application, a high quality USB-485 conversion module with function of electrical isolated is present in this paper. Electric level USB and RS485 are mutually converted by FT232BM combined with MAX1487. Optical coupling HC- PL600 is inset between the above two. Pulse transformer is inset in forward circuit for isolation. MC33063 is the core of switch pow- er supply, which supplies input for the transformer. Optical coupling PC817 is inset in feedback circuit for isolation. Voltage stability circuit regulate the output of the switch power supply. Hence, the isolated voltage could be stable. This module has a good test per- formance and could be applied.
出处
《自动化与仪器仪表》
2013年第6期45-46,49,共3页
Automation & Instrumentation
