Patent attributes
A power management circuit operable with low battery is provided. The power management circuit is configured to generate a time-variant average power tracking (APT) voltage based on a battery voltage supplied by a voltage source (e.g., battery). In examples disclosed herein, the power management circuit can be configured to remain operable when the battery voltage drops below a low battery threshold. Specifically, the power management circuit maintains the time-variant APT voltage at a constant level in response to the battery voltage dropping below the low battery threshold to thereby avoid drawing a rush current from the voltage source. As a result, a wireless device employing the power management circuit can remain operable with low battery to continue to support critical applications.