TECHNICAL FIELD

This relates generally to electronic circuitry, and more particularly to systems and methods for charging a battery.

BACKGROUND

A battery charger, or recharger, is a device used to put energy into a battery by forcing an electric current through the battery. A charging protocol of the battery indicates a voltage and/or current level, a duration, and what operations are executed when charging is complete. The charging protocol of the battery depends on the size and type of the battery being charged. Some battery types have high tolerance for overcharging (e.g., continued charging after the battery has been fully charged) and are rechargeable via connection to a constant voltage source or a constant current source. Some battery chargers employ a timer to cut off charging current at some fixed time, approximately when charging is complete. Other battery types cannot withstand overcharging, being damaged (reduced capacity, reduced lifetime), over heating or even exploding. Thus, the charger for such battery types includes a temperature and/or voltage sensing circuits and a microprocessor controller to safely adjust the charging current and voltage, determine the state of charge, and cut off at the end of a charge.

In electrical engineering, spikes are fast, short duration electrical transients in voltage (voltage spikes), current (current spikes), or transferred energy (energy spikes) in an electrical circuit. Excessive electric current during such a spike may destroy or severely weaken an electronic device.

SUMMARY

In a first example, a battery charger includes a battery power regulator configured to set a charge signal provided to a battery based on a charge control signal and charge enable signal. The battery charger also includes a controller configured to provide the charge control signal to the battery power regulator and temporarily de-assert the charge enable signal for a predetermined amount of time in response to determining that a change is needed in the charge control signal. The controller is also configured to re-assert the charge enable signal after the predetermined amount of time.

In a second example, a system includes a power regulator configured to provide power for charging a battery. The system also includes a battery power regulator configured to receive the power for charging the battery and set a charge signal provided to a battery based on a charge control signal and a charge enable signal. The system further includes a controller configured to provide the charge control signal to the battery power regulator based on a charge command signal received at the controller. The controller is also configured to temporarily de-assert the charge enable signal for a predetermined amount of time in response to the charge command signal commanding a change in the charge control signal, wherein de-assertion of the charge enable signal causes the battery power regulator to disable the charge signal. The controller is further configured to change the charge control signal based on the change in the charge command signal and re-assert the charge enable signal after the predetermined amount of time. The re-assertion causes the battery power regulator to re-enable the charge signal.

In a third example, a method for charging a battery includes applying, by a battery power regulator, a first charge signal to a battery based on a charge control signal and assertion of a charge enable signal. The method also includes determining, by a controller, that the charge control signal is to change and de-asserting, by the controller, the charge enable signal based on the determining, thereby causing the battery power regulator to disable the first charge signal. The method further includes changing, by the controller, the charge control signal in response to the de-asserting and re-asserting, by the controller, the charge enable signal a predetermined amount of time after the changing. The method yet further includes applying, by the battery power regulator, a second charge signal to the battery based on the changed charge control signal and the re-assertion of the charge enable signal.

