HART (Highway Addressable Remote Transducer) is one of the leading communication protocols worldwide within industrial applications, with the majority of smart field devices and intelligent process measurement and control systems utilising this communication technology. HART is a global standard and a bi-directional communication Protocol for sending and receiving digital information across analog, 4 to 20mA transmission lines. HART technology simultaneously transmits digital information with the 4-20mA signal and is an accompaniment to many of ADIs tailored industrial 4 to 20mA converters, like the AD5755, AD5422 or AD5421 families. HART technology is proven in practice, easy to use and very reliable. It is not a substitute for hardwired 4 to 20mA communication, but rather a complementary mode of communication which provides additional information in the form of remote diagnostics and system troubleshooting where it can be used to enhance the SIL (Safety Integrity Level) rating of a system. Analog Devices offers a family of HART Modems and complementary converters which can be used together to realise a robust, accurate and HART Foundation registered solution.