Method, system and device for switchless detection and charging

1. A charging device for charging an electronic smoking article, the charging device comprising the following:

(a) a device charging circuit configured (i) to selectively, electrically couple with an electronic smoking article circuit and (ii) to charge a rechargeable battery located within a portion of the electronic smoking article and comprising part of the electronic smoking article circuit, and

(b) a microcomputer configured to do the following: (i) use a pulse width modulation voltage signal to detect whether the charging circuit is electrically coupled with the electronic smoking article circuit, (ii) measure a charge level of the rechargeable battery, and (iii) use the measured charge level to determine a charge mode for charging the rechargeable battery;

wherein the microcomputer is configured to direct the device charging circuit to operate in a power-down mode when one or more of the following occur: the battery of the electronic smoking article circuit has a current below a first threshold value, the battery of the device charging circuit has a voltage below a second threshold value, or the device circuit has operated in a voltage servo charge mode for a predetermined period of time.

2. The charging device of claim 1 , wherein the microcomputer is further configured to detect whether the device charging circuit is electrically coupled with the electronic smoking article circuit by periodically supplying a source power supply signal from the device charging circuit to the electronic smoking article circuit.

3. The charging device of claim 2 , wherein the source power supply signal allows the electronic smoking article circuit to be electronically coupled to the device charging circuit for charging the electronic smoking article circuit.

4. The charging device of claim 2 , wherein the charging device further comprises a capacitor configured to be electronically coupled, in parallel, with the electronic smoking article circuit.

5. The charging device of claim 4 , wherein the microcomputer is configured to determine that the capacitor is electronically coupled with the electronic smoking article circuit when a voltage of the device charging circuit fails to rise above a predetermined threshold value.

6. The charging device of claim 5 , wherein the predetermined threshold value is between 4.5 volts and 6.0 volts.

7. The charging device of claim 1 , wherein the microcomputer is further configured to determine the charge mode based on one or more of the following: a voltage of a battery of the electronic smoking article circuit, a current of the battery of the electronic smoking article circuit, a voltage of a battery of the device charging circuit, or a time.

8. The charging device of claim 7 , wherein the microcomputer is configured to determine that when the voltage of the battery of the electronic charging circuit is below 3.0V, the charging circuit operates in a trickle charge mode to the electronic smoking article circuit.

9. The charging device of claim 7 , wherein the microcomputer is configured to determine that when the voltage of the battery of the electronic charging circuit is between 3.0V and 4.2V, the charging circuit operates in a current-servo charge mode to the electronic smoking article circuit.

10. The charging device of claim 7 , wherein the microcomputer is configured to determine that when the voltage of the battery of the electronic smoking article circuit is at or above 4.2V, the charging circuit operates in a voltage-servo charge mode to the electronic smoking article circuit.

11. The charging device of claim 1 , wherein the device comprises part of one of a docking station, a charging station, a charging pack, or a charging holder for the electronic smoking article.

12. The charging device of claim 1 , wherein the charging device further comprises a USB port or a wall outlet.