Giant Magneto Resistive (GMR) effect based Current Sensing Technique for DC/DC Converters

Abstract

Current sensing is one of the important function in a DC-DC Converter. It may be used for implementing current mode control or for achieving current sharing in a paralleled converters. Many current sensing schemes have been reported in literature, but they are either lossy or they require precise knowledge of the component value. In this paper a new Giant Magneto Resistive (GMR) effect based sensor is used for low voltage, high current VRM type applications. Since the current sensing is based on magnetic field, thus the sensing accuracy depends upon the placement of sensor on the conductor. Various implementation issues while using such a sensor are studied and finally the performance of the sensor is studied on a 1V/15A buck converter switching at 1MHz.

Hysteretic Modeling of Output Characteristics of Giant Magnetoresistive Current Sensors

“…With respect to current sensing, GMR sensors possess a good number of advantages over existing techniques, e.g., wide bands, high sensitivity, high stability, small size, low price, simple structure, low power consumption, and ease of integration. Up until now, GMR current sensors have been already successfully applied to various power electronic circuits [14]- [18].…”

Design Method of a Boost DC-DC Converter Circuit

“…Meanwhile, the increasement that current IC requires leads to a stronger capability of power supply output with load. These trends lead to increasingly demanding of DC-DC converter performance [6,7,8].…”