The MAXREFDES1171 uses Maxim® low-power chips for power grid fault indicators based on the low-power Arm® Cortex®-M4 processor. The MAXREFDES1171 is a high accuracy, low power, small and easily implanted design that can monitor the power status on the power grid line. Power grid coverage is widening in cities and the countryside, so power grid reliability and a short power-off time are important. The key requirements for a fault indicator are accuracy and very low power. One specification is that the unit must work for at least five years when in battery mode.
This document describes the hardware shown in Figure 1. It provides a detailed systematic technical guide to design in a small, low-power, high-accuracy fault indicator. The design has been built and tested, details of which follow later in this document.