Analytical compact modeling of GMR based current sensors: Application to power measurement at the IC level

An analytical compact model for giant magnetoresistance (GMR) based current sensors has been developed. Different spin-valve based full Wheatstone bridge sensors, with the current straps integrated in the chip, have been considered. These devices have been experimentally characterized in order to extract the model parameters. In this respect, we have focused on the sensors linear operation regime. The model, which allows the individual description of the magnetoresistive elements, has been implemented in a circuit simulator by means of a behavioral description language: Verilog-A. We also propose the use of the devices in a direct power measurement application at the integrated circuit (IC) level, by taking advantage of their multiplicative properties. A simple circuit is suggested, and analyzed in depth by means of the tested model, showing promising results regarding the application range.