Method and apparatus for improper power supply detection

A battery-operated device comprising:

• an internal battery having a battery current output;
• an internal power supply for receiving an external voltage and an external current from an external power supply and for generating a control signal in response to receiving the external voltage, the internal power supply in electronic communication with the internal battery;
• a processor in electronic communication with the internal battery, operative to determine a first polarity of the battery current output at a first time in response to the control signal, and operative to generate an error indicating the external power supply outputs insufficient power to the battery-operated device,
• wherein the error indicates the external power supply is improper and nonfaulty in response to the first polarity indicating the internal battery is consistently discharging while receiving the external voltage from the external power supply,
• wherein the error indicates the external power supply is faulty in response to the first polarity indicating the internal battery is intermittently discharging while receiving the external voltage from the external power supply;
• and
• a display operative to display a user warning indicative of an improper or faulty external power supply as indicated by the error.

An apparatus for detecting an improper external power supply coupled to a rechargeable battery equipped device, the apparatus comprising:

• a sensor operative to detect a connection of an external power supply and to generate a control signal in response to detecting the connection of the external power supply;
• an internal battery having a battery output current;
• a battery charging circuit operative for charging the internal battery in response to a power received from the external power supply;
• a processor powered by the internal battery and configured to receive the control signal, to detect a current polarity of the internal battery in response to the control signal, and to generate an error signal indicating the external power supply outputs insufficient power to the battery charging circuit,
• wherein the error signal indicates the external power supply is improper and nonfaulty in response to the current polarity indicating the internal battery is consistently discharging while receiving the power from the external power supply,
• wherein the error signal indicates the external power supply is faulty in response to the current polarity indicating the internal battery is intermittently discharging while receiving the power from the external power supply;
• and
• a user interface for displaying an improper power supply warning in response to the error signal.