Low-power STDR CMOS sensor for locating faults in aging aircraft wiring

A CMOS sensor used to locate intermittent faults on live aircraft wires is presented. A novel architecture was developed to implement the Sequence Time Domain Reflectometry method on a 0.5-mu m integrated circuit. The sensor locates short or open circuits on active wires with an accuracy of +/-1 ft when running at a clock speed of 100 MHz. A novel algorithm is proposed that utilizes the shape of the correlation peak to account for sub-bit delay, thus increasing the accuracy of fault location. The power consumed by the microchip is 39.9 mW.