Method for counting the number of puffs and aerosol generating device using the same

An aerosol generating device for generating aerosol by heating a liquid composition, the aerosol generating device comprising:

• a heater configured to heat the liquid composition;
• a sensor configured to measure a pressure in the aerosol generating device;
• and
• a controller configured to:
• obtain a first start time which is a time when the pressure measured by the sensor decreases below a first reference pressure value, the first reference pressure value being a value smaller than a pressure value which is measured by the sensor at an arbitrary time, after the power of the aerosol generating device is turned on and before a puff occurs,
• obtain a first end time which is a time when the pressure measured by the sensor reaches the first reference pressure value,
• determine whether a first period, which is a period between the first end time and the first start time, is longer than or equal to a first reference period,
• based on determining that the first period is longer than or equal to the first reference period, increase the number of puffs by one;
• and
• based on determining that the first period is shorter the first reference period, refrain from increasing the number of puffs by one,
• wherein the pressure measured by the sensor between the first start time and the first end time is less than the first reference pressure value.