Application Note 972 Inter-Operation of Interface Standards

When communication is required between systems that support different interfaces is required, a detailed study of driver output and receiver input characteristics is required to determine if direct “electrical” inter-operation is possible. The results of this study may also conclude that some translation devices are required for inter-operation. This may include passive devices or active devices, and even perhaps a repeater circuit. This application note focuses on the simplest way to gain electrical inter-operation between devices conforming to different Interface standards. Compatibility of various protocol and mechanical dimensions of connectors is beyond the scope of this application note, but must also be investigated to determine if inter-operation is possible. The following cases are covered, along with a discussion on important electrical characteristics of standard drivers and receivers. • Single-ended to Differential RS-232 to RS-422 TTL to RS-422