US 12,140,978 B2
Temperature control circuitry for an aerosol delivery device
Rajesh Sur, Winston-Salem, NC (US)
Assigned to RAI Strategic Holdings, Inc., Winston-Salem, NC (US)
Filed by RAI Strategic Holdings, Inc., Winston-Salem, NC (US)
Filed on Mar. 1, 2019, as Appl. No. 16/289,964.
Prior Publication US 2020/0278707 A1, Sep. 3, 2020
Int. Cl. G05D 23/24 (2006.01); G01K 7/16 (2006.01); H05B 1/02 (2006.01)
CPC G05D 23/2401 (2013.01) [G01K 7/16 (2013.01); H05B 1/0244 (2013.01)] 18 Claims
OG exemplary drawing
 
1. An aerosol delivery device comprising:
a power source configured to provide a voltage;
a heating element powerable to vaporize components of an aerosol precursor composition, the heating element having a resistance that is variable and proportional to a temperature of the heating element;
a power switch coupled to and between the power source and the heating element;
processing circuitry coupled to the power switch, and configured to output a signal during a heating time period to cause the power switch to switchably connect and disconnect the voltage provided by the power source to power the heating element, and measure an input heater voltage at the heating element that is equal or proportional to the voltage provided by the power source; and
a low-side current-sensing circuit coupled to and between the heating element and the processing circuitry, the low-side current-sensing circuit including a non-inverting operational amplifier circuit and shunt resistor, each coupled to an output of the heating element, and being configured to produce an output voltage on a connection between the low-side current-sensing circuit and the processing circuitry that is equal or proportional to an output heater voltage at the heating element,
wherein the processing circuitry is further configured to measure the output voltage, determine the resistance of the heating element from the input heater voltage, the output voltage, a gain of the non-inverting operational amplifier circuit, and a resistance value of the shunt resistor, determine the temperature of the heating element from the resistance, and adjust the signal when the temperature deviates from a predetermined set point.