Patent ID: 7509167
Filing Date: 2009-03-24
Classification: A61N

Abstract:
1. An implantable medical device, comprising: an inductive switching regulator having an inductor with a ferromagnetic core; a core saturation detector for detecting saturation in the inductor core of the inductive switching regulator indicating the presence of a magnetic field; wherein the inductive switching regulator alternately stores and discharges energy in an inductor in a two-phase power conversion cycle, the power conversion phases designated as fill and dump phases, respectively, such that the inductor current increases until a predetermined peak current value is reached during the fill phase and decreases to zero or other predetermined value during the dump phase; circuitry for measuring the duration of at least part of a power conversion cycle; wherein the core saturation detector detects core saturation if the duration of the measured duration of the power conversion cycle exceeds a specified threshold value; and, circuitry for altering the behavior of the device when core saturation is detected.