HART communication has the characteristics of simultaneous point-to-point 4 ~ 20 mA analog and digital communication, multi-station communication methods, and multiple transmissions.The HT1200M is compatible with the SYM20C15 and HT20C15 and with ON OnSemi's A5191HRT and HT2015.

The core challenge of HART hardware design lies in how to simultaneously carry a 4-20 mA DC analog signal, a 1200/2200 Hz FSK AC signal, and possible loop supply voltage on the same pair of wires, ensuring that the three do not interfere with each other and meet stringent industrial EMC standards. This chapter starts with the system architecture and analyzes the design key points layer by layer.

In the field of industrial automation, HART (Highway Addressable Remote Transducer) protocol serves as a core technological link connecting traditional analog equipment with modern digital management systems. Having undergone nearly forty years of industrial field validation, HART has become one of the most widely deployed field device communication protocols globally. By using Bell 202 FSK modulation technology, digital communication signals are superimposed on a traditional 4-20mA analog current loop, achieving dual-mode coexistence of " analog transmission + digital communication . " This design allows companies to endow existing equipment with digital capabilities such as remote configuration, real-time diagnostics, and multivariate transmission without interrupting existing control loops or re-laying cables.

Protocol: HART (HT1200M HART Communication Controller) Operating Temperature: -40-85°C(HT1200M HART Communication Controller) Dissipation Power: International Standard(HT1200M HART Communication Controller) Supply Voltage: 3.3-5.0V(HT1200M HART Communication Controller) Application: for the Fieldbus Instruments(HT1200M HART Communication Controller) D/C: 28pin, 32pin(HT1200M HART Communication Controller) Package: 28pin, 32pin(HT1200M HART Communication Controller) Compatibility: with HT20C15 and SYM20C15(HT1200M HART Communication Controller) Layer: Single Chip, FSK Modem(HT1200M HART Communication Controller) Operation Current: Less Than 200uA(HT1200M HART Communication Controller)