A temperature sensor comprising: a substrate, formed from a metal element, in particular a metal foil, wherein the substrate has a front and a rear side, an insulation layer, which covers the front side of the substrate only in some portions, in such a way that an insulation-layer-free portion is formed on the front side of the substrate, and a sensor structure, in particular a resistive sensor structure, which is formed on the insulation layer and insulation-layer-free portion of the front side of the substrate,
wherein the sensor structure has at least two electrical contacting portions, and a first contacting portion is connected to the insulation-layer-free portion of the front side of the substrate, and a second contacting portion is a first contact path or is connected to a first contact path, wherein the first contact path is preferably arranged on the insulation layer.

In an embodiment a sensor arrangement includes a ceramic-based substrate, at least one sensor chip connected directly to the substrate in a horizontal position by a bonding material, at least one first contact element and at least one second contact element configured to act as outer electrodes of the sensor arrangement, wherein the first contact element comprises a contact member configured to electrically contact the sensor chip by the bonding material and an insulating body enveloping the sensor chip and at least parts of the contact elements, wherein the substrate is mainly free from a material of the insulating body.

A positive temperature coefficient (PTC) heater apparatus is provided. The PTC heater apparatus includes a PTC heater, a resistance temperature detector (RTD) sensor mounted to the PTC heater and a controller logic unit electrically connected to the RTD sensor to receive readings of the RTD sensor, which, when the PTC heater is powered on, indicate whether the PTC heater is faulty.

A temperature measurement apparatus includes a base; a thermistor array including a plurality of thermistors in different regions of the base; a power supply circuit configured to supply power to any one of the plurality of thermistors; and a processor connected to the plurality of thermistors and the power supply circuit, and configured to determine a target thermistor among the plurality of thermistors, to control the power supply circuit to supply the power to the target thermistor, to detect a resistance value of the target thermistor, and to calculate a temperature of a region corresponding to the target thermistor on the basis of the resistance value of the target thermistor.

A method of calibrating temperature of a resistive element includes: generating a standard resistance-temperature (R-T) curve for the resistive element in an isothermal condition, wherein the resistive element comprises a material with a Curie temperature; generating an operational R-T curve for the resistive element during a normal operation of the resistive element; shifting the operational R-T curve toward the standard R-T curve at the Curie temperature to generate an adjusted operational R-T curve; and adjusting a measured temperature of the resistive element based on a resistance of the resistive element and the adjusted operational R-T curve.