Patent ID: 9148009
Filing Date: 2015-09-29
Classification: A24F,H02H,H02J,H02M

Abstract:
1. A charger with over-voltage and over-current protection configured to charge a battery of an electronic cigarette, comprising: a first interface configured to connect with an external power supply, and a second interface configured to connect with the battery; wherein the charger with over-voltage and over-current protection further includes a voltage stabilizing unit, a control unit, an input voltage sampling unit, a switch unit, and a current sampling unit; the control unit is connected to the voltage stabilizing unit, the input voltage sampling unit, the current sampling unit, and the switch unit respectively, the first interface is connected to the voltage stabilizing unit, the input voltage sampling unit, and the switch unit respectively, and the second interface is connected to the switch unit and the current sampling unit respectively; the voltage stabilizing unit is configured to receive an input voltage of the external power supply and provide a constant working voltage to the control unit; the input voltage sampling unit is configured to detect the input voltage real-timely; the current sampling unit is configured to detect charging current of the battery real-timely; the control unit is configured to determine whether the input voltage detected by the input voltage sampling unit generates over-voltage or not, or determine whether the charging current detected by the current sampling unit generates over-current or not, and control the switch unit to turn on or turn off according to the determination results; the switch unit is configured to receive the input voltage and output an output voltage to the second interface to charge the battery when the switch unit is turned on under the control of the control unit; the control unit includes a microprocessor; the switch unit includes a PNP transistor, an NPN transistor, a second resistor, and a third resistor; the emitter of the PNP transistor is connected to a voltage output end of the first interface, the collector of the PNP transistor is connected to a positive output end of the second interface, and the base of the PNP transistor is connected to the collector of the NPN transistor; the base of the NPN transistor is connected to a first output of the microprocessor via the third resistor, and the emitter of the NPN transistor is grounded; one end of the second resistor is connected to the base of the PNP transistor, and the other end of the second resistor is connected to the emitter of the PNP transistor.