Magnetic field strength detector

A magnetic field strength detector comprising:

• a coil, wherein voltage is induced across the coil as a function of magnetic field strength;
• a capacitive element coupled to the coil that stores energy as a function of the voltage induced across the coil, and outputs voltage as a function of the stored energy;
• and
• an indicator that alters as a function of the voltage output by the capacitive element when the magnetic field strength exceeds a threshold, wherein the alteration of the indicator is substantially irreversible.

A magnetic field strength detector comprising:

• a magnetic field sensing element that outputs voltage as a function of magnetic field strength;
• an indicator that alters as a function of the voltage output by the magnetic field detector when the magnetic field strength exceeds a threshold wherein the alteration of the indicator is substantially irreversible;
• and
• a heating element coupled to the sensing element that generates heat as a function of the voltage output by the sensing element,
• wherein the indicator comprises a phase change material, and an appearance of the phase change material alters when a temperature of the phase change material exceeds a threshold.

A magnetic field strength detector comprising:

• a magnetic field sensing element that outputs voltage as a function of magnetic field strength;
• an indicator that alters as a function of the voltage output by the magnetic field detector when the magnetic field strength exceeds a threshold, wherein the alteration of the indicator is substantially irreversible;
• and
• a plurality of substrate layers, wherein each of the magnetic field detector, and the indicator are formed on at least one of the substrate layers by at least one of electroforming, vacuum sputtering, vapor deposition, and etching.

A magnetic field strength detector comprising:

• a coil, wherein voltage is induced across the coil as a function of magnetic field strength;
• a fuse element coupled to the coil that fails based on a current presented to the fuse element as a result of the voltage induced across the coil when the magnetic field strength exceeds a threshold;
• and
• a plurality of substrate layers, wherein each of the coil and the fuse element are formed on at least one of the substrate layers.