Powerless time reference
AssigneeNXP B.V.
InventorThomas Suwald
Life of this patent
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Abstract
According to an embodiment, a time reference device is provided. In the embodiment, the time reference device, includes a corrodible element, wherein a corrosion of the corrodible element advances with advancing time, and a sensor configured for providing a sensor signal, the sensor signal depending on a physical property of the corrodible element; wherein the physical property of the corrodible element changes with a corrosion of the corrodible element and the physical property of the corrodible element is at least one of an electrical property, a magnetic property, and an optical property. A barrier may be provided for defining a permeability for a corrosive substance to the corrodible element.
Claims14
A time reference device comprising:
- a corrodible element, wherein a corrosion of the corrodible element advances with advancing time;
- wherein the corrosion of the corrodible element occurs without the requirement of electrical power;
- and
- wherein the corrodible element forms a first electrode of a capacitor, the capacitor further comprising a counter electrode, the counter electrode and the first electrode forming the capacitor whose capacitance is altered by the corrosion of the corrodible element;
- and
- a sensor configured for providing a sensor signal, the sensor adapted to sense the capacitance of the capacitor a barrier, the barrier providing a defined permeability for a corrosive substance through the barrier to the corrodible element, the corrosive substance generating the corrosion of the corrodible element;
- and a further barrier, the further barrier providing a defined permeability for the corrosive substance through the further barrier to a reference element;
- wherein the defined permeability provided by the further barrier for the reference element is lower than the defined permeability provided by the barrier for the corrodible element.
A method for providing a sensor signal indicative of an elapsed time, the method comprising:
- providing a corrodible element;
- allowing the corrodible element to corrode with time;
- wherein the corrosion of the corrodible element occurs without the requirement of electrical power;
- wherein the corrodible element forms a first electrode of a capacitor, the capacitor further comprising a counter electrode, the counter electrode and the first electrode forming the capacitor whose capacitance is altered by the corrosion of the corrodible element;
- and
- providing a sensor signal by sensing the capacitance of the capacitor providing a barrier with a defined permeability for a corrosive substance, the corrosive substance generating the corrosion of the corrodible element;
- providing a further barrier with a defined permeability for the corrosive substance to a reference element;
- wherein the defined permeability of the corrosive substance through the further barrier to the reference element is lower than the defined permeability of the corrosive substance through the barrier to the corrodible element.
Dependencies are inferred from the claim text.