Monitoring a battery in a portable electronic device

摘要

The disclosed embodiments provide a system that monitors a battery in a portable electronic device. During operation, the system monitors a state of charge of the battery while the battery is powering the portable electronic device. Next, when the state of charge of the battery reaches a predetermined reserve capacity, the system monitors a voltage of the battery. Then, when the monitored voltage of the battery reaches a predetermined termination voltage, the system puts the portable electronic device into a low power usage state.

主权项

1. A method for monitoring a battery in a portable electronic device, comprising:
while monitoring a state of charge of the battery while the battery is powering the portable electronic device: if the state of charge is found to be above a predetermined reserve capacity, continuing to monitor the state of charge; if the state of charge is found to be equal to or less than the predetermined reserve capacity, switching from monitoring the state of charge to monitoring a voltage of the battery; while monitoring the voltage while the battery is powering the portable electronic device: if the monitored voltage is equal to or less than a predetermined termination voltage: if the monitored voltage meets a first criteria, performing at least one action that reduces a power drawn by the portable electronic device from the battery while keeping the portable electronic device running, the first criteria comprising whether a frequency of transient voltage dips below the predetermined termination voltage exceeds a predetermined frequency of transient voltage dips below the predetermined termination voltage; if the monitored voltage meets a second criteria, putting the portable electronic device into one of a shutdown state and a hibernate state, the second criteria comprising whether a steady-state voltage measurement of the monitored voltage is equal to or below the predetermined termination voltage; wherein the predetermined termination voltage is above the portable electronic device's brownout voltage.