The present invention relates in one aspect to an infusion fluid warmer which comprises a casing shell having an upper wall structure and a lower, opposing, wall structure. The casing shell encloses a fluid channel or passage extending through the casing shell in-between the upper and lower wall structures and fluid inlet and outlet ports coupled to opposite ends of the fluid channel or passage to allow a flow of infusion fluid through the casing shell. A housing shell is formed in a thermally conducting and electrically insulating material and a heating element is bonded to the housing shell and thermally coupled thereto. The fluid channel or passage extends through the housing shell or extends around the housing shell such that heat energy is transferred to the infusion fluid by direct physical contact with housing shell material.

An aerosol-generating system including a cartridge is provided, the cartridge including a liquid storage portion including a housing configured to hold a liquid aerosol-forming substrate, the housing having an opening; and a heater assembly including at least one heater element fixed to the housing and extending across an opening of the housing, wherein a width of the at least one heater element of the heater assembly is smaller than a width of the opening of the housing. The heater element may be spaced from a periphery of the opening, leading to more efficient heating and aerosol production.

A method for operating a heater system including a resistive heating element having a material with a non-monotonic resistivity vs. temperature profile is provided. The method includes heating the resistive heating element to within a limited temperature range in which the resistive heating element exhibits a negative dR/dT characteristic, operating the resistive heating element within an operating temperature range that at least partially overlaps the limited temperature range, and determining a temperature of the resistive heating element such that the resistive heating element functions as both a heater and a temperature sensor. The resistive heating element can function as a temperature sensor in a temperature range between about 500° C. and about 800° C., and the non-monotonic resistivity vs. temperature profile for the material of the resistive heating element can have a local maximum and a local minimum.

A method for operating a glow plug includes controlling a temperature of the glow plug by switching between applying a voltage V.sub.H and applying a voltage V.sub.N<V.sub.H to the glow plug. Applying the voltage V.sub.H and applying the voltage V.sub.N causes a glow plug current to oscillate about a glow plug current threshold. The glow plug current threshold is associated with one of the voltage V.sub.H and the voltage V.sub.N. The method includes monitoring the glow plug current at the one of the voltage V.sub.H and the voltage V.sub.N.

An integrated circuit (IC) heater circuit comprises a drive circuit configured to increase the temperature of the IC when consuming power; a temperature sensor coupled to a control node of the drive circuit to activate and deactivate the drive circuit to provide an ambient temperature for the IC, wherein current of the temperature sensor varies with temperature; and a control circuit coupled to the temperature sensor and configured to adjust variation in the temperature sensitivity of the current of the temperature sensor.

Control device for aerosol inhalation device, includes operational amplifier including output terminal configured to generate voltage according to voltage applied to load configured to heat aerosol source and having correlation between temperature and electrical resistance value, control unit including input terminal and configured to perform processing based on voltage applied to the input terminal, and voltage dividing circuit configured to electrically connect the output terminal of the operational amplifier and the input terminal of the control unit. Power supply voltage of the operational amplifier is higher than power supply voltage of the control unit, and equals voltage applied to aerosol generation circuit including the load, and one of inverting input terminal and noninverting input terminal of the operational amplifier is electrically connected to the aerosol generation circuit.

A power supply unit for an aerosol inhaler, which includes a power supply configured to discharge electricity to a load that is configured to heat an aerosol generation source and has a correlation between temperature and electric resistance values, includes: a first element connected in series to the load and having a first electric resistance value; a second series circuit that includes a second element having a second electric resistance value, and a third element connected in series to the second element and having a third electric resistance value, the second series circuit being connected in parallel with a first series circuit including the load and the first element; and an operational amplifier connected to the first series circuit and the second series circuit. The first electric resistance value is less than an electric resistance value of the load.

In an embodiment an electro-thermal device includes a heater, a readout circuit, a digital controller having a first input coupled to a first output of the readout circuit and a digital sigma-delta modulator having a first input coupled to an output of the digital controller and an output coupled to the heater.

Various example embodiments relate to a non-nicotine electronic vaping device, system, method, and/or non-transitory computer readable medium for protecting a non-nicotine electronic vaping device from overheating based on a steady state resistance prediction. The non-nicotine electronic vaping device may include a reservoir containing a non-nicotine pre-vapor formulation, the non-nicotine pre-vapor formulation being devoid of nicotine and including at least one non-nicotine compound, a heating element configured to heat non-nicotine pre-vapor formulation drawn from the reservoir, and control circuitry configured to monitor a resistance value of the heating element over a first time period after a first application of negative pressure to the non-nicotine electronic vaping device, determine an estimated steady state resistance value of the heating element based on the monitored resistance value using a trained neural network, and control power to the heating element based on the estimated steady state resistance value.

Various example embodiments relate to a nicotine electronic vaping device, system, method, and/or non-transitory computer readable medium for protecting a nicotine electronic vaping device from overheating based on a steady state resistance prediction. The nicotine electronic vaping device may include a reservoir containing a nicotine pre-vapor formulation, a heating element configured to heat nicotine pre-vapor formulation drawn from the reservoir, and control circuitry configured to monitor a resistance value of the heating element over a first time period after a first application of negative pressure to the nicotine electronic vaping device, determine an estimated steady state resistance value of the heating element based on the monitored resistance value using a trained neural network, and control power to the heating element based on the estimated steady state resistance value.