Power supply unit for aerosol generation device

A power supply unit for an aerosol generation device, the power supply unit comprising:

• an internal power supply configured to hold power supplied to a heater configured to heat an aerosol source;
• a connector connectable to an external power supply;
• a controller configured to control power supply from the internal power supply to the heater;
• a first transistor of a dropper type positioned on a first power supply path between the connector and a positive electrode of the internal power supply;
• a circuit board mounted with the controller and including ground;
• and
• a current detection circuit configured to detect at least one of a first current flowing from a negative electrode of the internal power supply at the time of charging the internal power supply and a second current flowing into the negative electrode of the internal power supply at the time of discharging from the internal power supply,
• wherein a current from the connector is supplied to a source of the first transistor, and a current from a drain of the first transistor is supplied to the positive electrode of the internal power supply,
• the controller performs feedback control on a voltage of a gate of the first transistor based on a current or a voltage supplied from the first transistor, thereby adjusting power supplied from the external power supply to the internal power supply, and
• wherein the negative electrode of the internal power supply is not connected to the ground of the power supply unit.