Low Power Silicon Carbide RS-485 Transceiver

This paper describes the first RS-485 transceiver for high temperature applications designed in SiC-CMOS. The transceiver was designed and developed in a 1.2μm CMOS HiTSiC® process from Raytheon UK. It has been tested at a voltage supply of 15 V from temperatures of 25°C to 400°C. At 320°C, the rise and fall times are 40 ns (for both), and the propagation delay from driver to output high and to output low is 150 ns and 50 ns respectively. The transceiver has been demonstrated to operate over 700 m of Cat5 cable. A high temperature data acquisition and transmission system has potential applications such as deep earth drilling, remote connection to high temperature locations, and high temperature data acquisition.