The Effect of Return Path Current on Analog Sensor Readings in Mixed-Signal Embedded Applications

Abstract

This paper provides an experimental analysis on the effect of various ground configurations on circuit current return paths. It provides an in-depth investigation of corrupted voltage readings in analog-to-digital converters (ADCs), which leads to inaccurate sensor readings and may cause system instability in embedded applications. In the ever-expanding field of robotics the electric motor is a fundamental component. Wheeled, legged, flying, swimming, stationary, swarming, and other types of robots require some sort of actuator to provide motion to the specific system part, or of the entire system. This analysis examines DC and servo motors noise produced in readings obtained from selected voltage, temperature, and distance analog sensors. PSoC-based CY8CKIT-001 Development Board and PSoC-based EagleSoC Development Board demonstrate how the separation of ground lines in the mixed-signal PCB circuit ensures accurate analog sensor readings.