Design Of Photo-MOS Solid-state Relay

Photo-MOS solid-state relay is the product of solid-state relay development to miniaturization and low-cost.It is based on light-emitting diodes,photodiode array as an isolated coupling device,power FET as an integrated output devices,with high-speed switching function of the miniaturization of solid-state relay.Because of its small size,light weight,drive current is small,the general single-chip I / O port,TTL circuit can directly control the Photo-MOS solid relay for electrical control,the use of very convenient.Photo-MOS solid relays can be used in measuring instruments,communication equipment,medical equipment,machine tools,industrial equipment and other fields according to different output characteristics such as high voltage,power type and low on-resistance type.In this paper,the working principle of Photo-MOS solid-state relay is studied.The circuit design,structural design and thermal design of the Photo-MOS solid relay are studied and applied in the actual design,to achieve the JGW-3019 PhotoMOS solid-state relay design and development work.Firstly,the principle circuit of the Photo-MOS solid-state relay is studied,and the advantages and disadvantages of various control circuits are analyzed.The circuit with input anti-reverse,fast release and anti-jamming capability is designed.According to JGW-3019 Photo-MOS solid-state relay technical requirements,the selection of components,and the use of "electronic equipment reliability prediction manual" solid relay reliability prediction method is expected to reliability.Secondly,designed a direct light mode.The optimal illumination distance is obtained by the calculation of light intensity.On this basis,the structure design of Photo-MOS solid-state relay is carried out.Through the establishment of threedimensional model,ANSYS simulation software the sixth order modal analysis and random vibration analysis verify the rationality of structural design.Thirdly,the heat dissipation path of JGW-3019 Photo-MOS solid relay is analyzed,and the external thermal resistance and internal thermal resistance and the temperature rise of the relay are calculated.The derating design of the output current is carried out according to the calculated results.The thermal analysis of the product was carried out by ANSYS simulation software,and the feasibility of the output current derating was verified.Finally,the mass production of JGW-3019 type Photo-MOS solid relay was realized.The functional parameters,structural design,thermal design and reliability were verified by the test method specified in GJB1515 A "General specification of solid-state relay".The design index was satisfied The requirements of the subject,and according to the production of the qualified rate of statistics.