Charging circuit, charging apparatus, electronic equipment and charging method
View Patent ↗A charging circuit includes a monitoring part configured to monitor a battery voltage applied to a battery and configured to output an overvoltage signal when the battery is in an overvoltage condition a protection part configured to electrically disconnect the battery from an adaptor when receiving the overvoltage signal, and a switch which, when the battery is electrically disconnected from the adaptor, switches a monitoring node for an adaptor voltage outputted from the adaptor, from a supply node of the battery voltage to a supply node of a system voltage, which is applied to a system electrically connected with the battery and the adaptor, based on the overvoltage signal to cause a control command for controlling the adaptor voltage based on the system voltage to be outputted.
1. A charging circuit comprising:
a monitoring part configured to monitor a battery voltage applied to a battery at a supply node of the battery voltage and configured to output an overvoltage signal when the battery is in an overvoltage condition;
a protection part configured to electrically disconnect the battery from an adaptor when receiving the overvoltage signal; and
a switch which, when the battery is electrically disconnected from the adaptor, switches a monitoring node for monitoring an adaptor voltage outputted from the adaptor, from the supply node of the battery voltage to a supply node of a system voltage, which is applied to a system electrically connected with the battery and the adaptor and is different from the supply node of the battery voltage, based on the overvoltage signal to cause a control command for controlling the adaptor voltage based on the system voltage to be outputted.
2. The charging circuit according to claim 1 , wherein the adaptor is configured to adjust the adaptor voltage when it receives the control command.
3. The charging circuit according to claim 1 comprising:
a breaking part configured to electrically disconnect a command output circuit from a control circuit when the monitoring node is switched by the switch;
wherein the command output circuit is configured to output the control command based on the overvoltage signal issued from the monitoring part, and wherein the control circuit is configured to manage the operation of the command output circuit.
4. The charging circuit according to claim 1 , wherein the switch comprises:
a battery-side switching contact electrically connected between a voltage monitoring circuit configured to monitor an output state of the adaptor voltage and the supply node of the battery voltage; and
a system-side switching contact electrically connected between the voltage monitoring circuit and the supply node of the system voltage, wherein, when the battery and the adaptor are electrically connected, the switch is configured to turn off the system-side switching contact, based on the overvoltage signal, while keeping the battery-side switching contact on so that the supply node of the battery voltage supplies as the monitoring node, and, when the battery and the adaptor are electrically disconnected, the switch is configured to turn on the system-side switching contact, based on the overvoltage signal, while keeping the battery-side switching contact off so that the supply node of the system voltage supplies as the monitoring node.
5. The charging circuit according to claim 1 , wherein the switch comprises:
a connection contact electrically connected between a voltage monitoring circuit configured to monitor an output state of the adaptor voltage and a command output circuit configured to output the control command; and
a capacitor electrically connected in parallel between the command output circuit and the connection contact, wherein, when the battery and the adaptor are electrically connected, the switch is configured to feed the output of the voltage monitoring circuit to the command output circuit by turning on the connection contact based on the overvoltage signal to cause the command output circuit to generate the control command, and, when the battery and the adaptor are electrically disconnected, the switch turns off the connection contact based on the overvoltage signal and clamps the control command.
6. The charging circuit according to claim 1 , wherein the monitoring part is configured to compare the battery voltage from the supply node of the battery voltage with a reference voltage to detect overvoltage to the battery, and wherein the reference voltage is input to the charging circuit.
7. The charging circuit according to claim 1 , wherein the monitoring part is configured to compare the battery voltage from the supply node of the battery with a reference voltage to detect overvoltage to the battery, and wherein the reference voltage is generated within the charging circuit.
8. The charging circuit according to claim 1 , wherein the protection part is provided between the supply node of the battery voltage and the supply node of the system voltage.