Supporting files for "A low power dual-voltage RS-485 to TTL signal converter for Modbus RTU sensor"

We introduce RS-485LP, an open-source hardware project designed to bridge industrial sensors with modern microcontrollers. The device utilizes a MAX487 transceiver to support up to 128 nodes while offering native 3.3V and 5V logic compatibility, eliminating the need for external level shifters. Its primary innovation is a logic-controlled shutdown mechanism that addresses the power management deficiencies found in conventional converters, making it specifically optimized for battery-powered IoT nodes. Experimental validation demonstrates that the module’s shutdown mode achieves a 3.52% energy saving compared to standard idle states while maintaining stable data acquisition during environmental monitoring. Certified by OSHWA and costing approximately $7.93 to produce, the RS-485LP provides a cost-effective, reliable solution for professional remote monitoring and serves as a practical pedagogical tool for teaching power-aware industrial-to-digital interfacing.