Patent attributes
An electrically heated smoking system is provided, including a secondary unit configured to receive a smoking article having an aerosol-forming substrate. The secondary unit includes at least one heating element, an interface configured to connect to a primary power supply, a secondary power supply, and secondary circuitry. The secondary circuitry is configured to control supply of electrical power from the secondary supply to the heating element (a) in a pre-heating mode, during which a substrate temperature is increased to an operating temperature, and (b) in a smoking mode, during which a substrate temperature is maintained at substantially the operating temperature; and to control charging of the secondary supply by the primary supply in a charging mode, to have sufficient charge to increase a substrate temperature to the operating temperature in the pre-heating mode and to maintain the substrate temperature at substantially the operating temperature during the smoking mode.
