Buck regulator with operational amplifier feedback for an aerosol delivery device

• US 10,813,385 B2
• Filed: 03/09/2018
• Issued: 10/27/2020
• Est. Priority Date: 03/09/2018
• Status: Active Grant

• Current Assignee: RAI STRATEGIC HOLDINGS, INC. (British American Tobacco PLC)
• Original Assignee: RAI STRATEGIC HOLDINGS, INC. (British American Tobacco PLC)
• Inventors: Sur, Rajesh
• Primary Examiner(s): Riyami, Abdullah A
• Assistant Examiner(s): Nguyen, Thang H
• Application Number:
  US15/916,696
• Publication Number:
  US 20190274353A1
• Time in Patent Office: 963 Days
• Field of Search: 131329
• CPC Class Codes: A24B 15/167 in liquid or vaporisable form, e.g. liquid compositions for electronic cigarettes
• CPC Class Codes: A24F 40/10 Devices using liquid inhalable precursors
• CPC Class Codes: A24F 40/20 Devices using solid inhalable precursors
• CPC Class Codes: A24F 40/30 Devices using two or more structurally separated inhalable precursors, e.g. using two liquid precursors in two cartridges
• CPC Class Codes: A24F 40/50 Control or monitoring
• CPC Class Codes: A61M 11/042 electrical
• CPC Class Codes: A61M 15/06 Inhaling appliances shaped like cigars, cigarettes or pipes
• CPC Class Codes: A61M 2016/0024 with an on-off output signal, e.g. from a switch
• CPC Class Codes: A61M 2016/0027 pressure meter
• CPC Class Codes: A61M 2016/0039 in the inspiratory circuit
• CPC Class Codes: A61M 2205/3317 Electromagnetic, inductive or dielectric measuring means
• CPC Class Codes: A61M 2205/3653 by Joule effect, i.e. electric resistance
• CPC Class Codes: A61M 2205/50 with microprocessors or computers
• CPC Class Codes: A61M 2205/582 by tactile feedback
• CPC Class Codes: A61M 2205/583 by visual feedback
• CPC Class Codes: A61M 2205/587 Lighting arrangements
• CPC Class Codes: A61M 2205/8206 battery-operated
• CPC Class Codes: H02M 3/156 with automatic control of output voltage or current, e.g. switching regulators

Abstract

An aerosol delivery device is provided that includes a heating element configured to convert electricity to heat and thereby vaporize components of an aerosol precursor composition, and a control component coupled to and configured to controllably power the heating element. The control component includes a buck regulator circuit coupled to the heating element, and an operational amplifier circuit coupled to the heating element and buck regulator circuit. The buck regulator circuit is configured to step down voltage and step up current from a power source to the heating element to thereby power the heating element. The operational amplifier circuit is configured to amplify an output voltage from the heating element to produce a higher voltage that is fed back to the buck regulator circuit, which is configured to use the higher voltage to regulate an output voltage from the buck regulator circuit to the heating element.

Claims

1. An aerosol delivery device comprising:

a housing structured to retain an aerosol precursor composition;

a heating element configured to convert electricity to heat and thereby vaporize components of the aerosol precursor composition;

a positive terminal to which a power source is connected or connectable;

a control component coupled to and configured to controllably power the heating element, the control component including;

a buck regulator circuit coupled to the heating element, and configured to step down voltage and step up current from the power source to the heating element to thereby power the heating element;

an operational amplifier circuit coupled to the heating element and buck regulator circuit, and configured to amplify an output voltage from the heating element to produce a higher voltage that is fed back to the buck regulator circuit; and

a high-side load switch between the buck regulator circuit and the positive terminal, the high-side load switch configured to connect and disconnect the power source to and from a load including the heating element, and limit input current to the buck regulator circuit; and

a sensor between the positive terminal and the high-side load switch, the sensor configured to produce a measurement of pressure caused by airflow through at least a portion of the aerosol delivery device, and convert the measurement of pressure to a corresponding electrical signal,

wherein the control component further includes a processor configured to receive the corresponding electrical signal and control the high-side load switch to connect the power source to the load in response thereto, and

wherein the buck regulator circuit includes a power stage configured to step down the voltage and step up the current from the power source, and a feedback control circuit configured to use the higher voltage from the operational amplifier circuit to regulate an output voltage from the buck regulator circuit to the heating element.

2. The aerosol delivery device of claim 1, wherein the feedback control circuit includes an error amplifier and a pulse width modulation (PWM) comparator, the error amplifier being configured to produce a control voltage based on a comparison of the higher voltage and a reference voltage, and the PWM comparator being configured to use the control voltage to produce a PWM waveform that is used to regulate the output voltage from the buck regulator circuit to the heating element.

3. The aerosol delivery device of claim 1, wherein the operational amplifier circuit is a non-inverting operational amplifier circuit.

4. The aerosol delivery device of claim 1 further comprising a resistor coupled in series between the operational amplifier circuit and the buck regulator circuit, the resistor being configured to limit current fed back to the buck regulator circuit from the operational amplifier circuit.

5. The aerosol delivery device of claim 1, wherein the aerosol precursor composition is a liquid, or a solid or semi-solid.

6. The aerosol delivery device of claim 1, wherein the aerosol precursor composition is a first aerosol precursor composition that is a solid or semi-solid, the heating element is a first heating element configured to vaporize components of the first aerosol precursor composition, and the aerosol delivery device further comprises:

terminals coupled or coupleable to a second heating element of a cartridge configured to retain a second aerosol precursor composition that is a liquid, and the second heating element being configured to convert electricity to heat and thereby vaporize components of the second aerosol precursor composition, and

wherein the control component further includes a switch coupled to an output of the buck regulator circuit and switchable to provide an output voltage and current from the buck regulator circuit to the first heating element or the second heating element.

7. The aerosol delivery device of claim 6, wherein the switch is switchable to provide the output voltage and current from the buck regulator circuit to the first heating element when the second heating element is not coupled to the terminals, and to the second heating element when the second heating element is coupled to the terminals.

8. The aerosol delivery device of claim 7, wherein the control component further includes:

one or more logic gates with a first input coupled to the output of the buck regulator circuit between the buck regulator circuit and the switch, a second input coupled to the processor, and an output coupled to the switch, wherein the output voltage from the buck regulator circuit causes a logical high level of voltage at the first input of the one or more logic gates, and

wherein the processor is configured to determine when the second heating element is coupled to the terminals, and to cause a first logical level of voltage at the second input of the one or more logic gates when the second heating element is not coupled to the terminals to cause a logical low level of voltage at the output of the one or more logic gates that is configured to control the switch to provide the output voltage and current to the first heating element, and the processor is configured to cause an opposite, second logical level of voltage at the second input of the one or more logic gates when the second heating element is coupled to the terminals to cause a logical high level of voltage at the output of the one or more logic gates that is configured to control the switch to provide the output voltage and current to the second heating element.

9. A control body for an aerosol delivery device, the control body comprising:

a positive terminal to which a power source is connected or connectable;

a control component coupled to and configured to controllably power a heating element configured to convert electricity to heat and thereby vaporize components of an aerosol precursor composition, the control component including;

a buck regulator circuit coupled to the heating element, and configured to step down voltage and step up current from the power source to the heating element to thereby power the heating element;

an operational amplifier circuit coupled to the heating element and buck regulator circuit, and configured to amplify an output voltage from the heating element to produce a higher voltage that is fed back to the buck regulator circuit; and

a high-side load switch between the buck regulator circuit and the positive terminal, the high-side load switch configured to connect and disconnect the power source to and from a load including the heating element, and limit input current to the buck regulator circuit; and

a sensor between the positive terminal and the high-side load switch, the sensor configured to produce a measurement of pressure caused by airflow through at least a portion of the aerosol delivery device, and convert the measurement of pressure to a corresponding electrical signal,

wherein the control component further includes a processor configured to receive the corresponding electrical signal and control the high-side load switch to connect the power source to the load in response thereto, and

wherein the buck regulator circuit includes a power stage configured to step down the voltage and step up the current from the power source, and a feedback control circuit configured to use the higher voltage from the operational amplifier circuit to regulate an output voltage from the buck regulator circuit to the heating element.

10. The control body of claim 9, wherein the feedback control circuit includes an error amplifier and a pulse width modulation (PWM) comparator, the error amplifier being configured to produce a control voltage based on a comparison of the higher voltage and a reference voltage, and the PWM comparator being configured to use the control voltage to produce a PWM waveform that is used to regulate the output voltage from the buck regulator circuit to the heating element.

11. The control body of claim 9, wherein the operational amplifier circuit is a non-inverting operational amplifier circuit.

12. The control body of claim 9 further comprising a resistor coupled in series between the operational amplifier circuit and the buck regulator circuit, the resistor being configured to limit current fed back to the buck regulator circuit from the operational amplifier circuit.

13. The control body of claim 9, wherein the aerosol precursor composition is a liquid, or a solid or semi-solid.

14. The control body of claim 9, wherein the control body includes the heating element that is a first heating element configured to vaporize components of a first aerosol precursor composition that is a solid or semi-solid, and terminals coupleable to a second heating element configured to convert electricity to heat and thereby vaporize components of a second aerosol precursor composition that is a liquid, and

wherein the control component further includes a switch coupled to an output of the buck regulator circuit and switchable to provide an output voltage and current from the buck regulator circuit to the first heating element or the second heating element.

15. The control body of claim 14, wherein the switch is switchable to provide the output voltage and current from the buck regulator circuit to the first heating element when the second heating element is not coupled to the terminals, and to the second heating element when the second heating element is coupled to the terminals.

16. The control body of claim 15, wherein the control component further includes:

one or more logic gates with a first input coupled to the output of the buck regulator circuit between the buck regulator circuit and the switch, a second input coupled to the processor, and an output coupled to the switch, wherein the output voltage from the buck regulator circuit causes a logical high level of voltage at the first input of the one or more logic gates, and

wherein the processor is configured to determine when the second heating element is coupled to the terminals, and to cause a first logical level of voltage at the second input of the one or more logic gates when the second heating element is not coupled to the terminals to cause a logical low level of voltage at the output of the one or more logic gates that is configured to control the switch to provide the output voltage and current to the first heating element, and the processor is configured to cause an opposite, second logical level of voltage at the second input of the one or more logic gates when the second heating element is coupled to the terminals to cause a logical high level of voltage at the output of the one or more logic gates that is configured to control the switch to provide the output voltage and current to the second heating element.