Detection and compensation of multiplexer leakage current

摘要

A multiplexed input/output (I/O) system detects leakage currents on a selected input channel. The system includes a leakage detection multiplexer connected to provide an output selected from one of a plurality of input channels. In addition, the leakage detection multiplexer provides as part of the output measured leakage currents associated with the selected input channel. Based on the detected leakage currents, a determination can made regarding whether the detected leakage currents have compromised the integrity of the multiplexer output. In addition, the detected leakage current can be used to compensate the output provided by the multiplexer to account for the presence of leakage currents on the selected channel.

主权项

1. A multiplexed input/output (I/O) system including:
a leakage detection multiplexer for receiving a sensor input at each of a plurality of input channels, for providing a sensor output selected from one of the plurality of input channels at an output channel associated with the selected input channel, and for providing a leakage output indicative of leakage current associated with a selected input channel at the output channel associated with the selected input channel, wherein the leakage detection multiplexer includes at least one leakage sense resistor connected to each of plurality of input channels, wherein the leakage output represents the voltage across the leakage sense resistor associated with the selected input channel; and a controller for generating a notification when the output indicative of leakage current exceeds a threshold value indicating a loss of integrity associated with the selected input channel.