Switched-mode power supply chargers with fault detection related to limited power source protection

A power supply charger comprising:

• a first transistor configured to provide an output current of the power supply charger and an output voltage of the power supply charger;
• a first resistor configured to receive a resistor current that is equal to the output current in magnitude;
• and
• a fast charging protocol controller coupled to the first transistor and the first resistor;
• wherein the fast charging protocol controller includes:
• a first transistor voltage-drop detector configured to detect a first transistor voltage drop from a first drain of the first transistor to a first source of the first transistor;
• a resistor voltage-drop detector configured to detect a resistor voltage drop from a first resistor terminal of the first resistor to a second resistor terminal of the first resistor;
• and
• a logic controller coupled to the first transistor voltage-drop detector and the resistor voltage-drop detector;
• wherein the first transistor voltage-drop detector is further configured to:
• compare the detected first transistor voltage drop with a first threshold voltage to generate a first comparison signal;
• and
• compare the detected first transistor voltage drop with a second threshold voltage to generate a second comparison signal;
• wherein the resistor voltage-drop detector is further configured to:
• compare the detected resistor voltage drop with a third threshold voltage to generate a third comparison signal;
• and
• compare the detected resistor voltage drop with a fourth threshold voltage to generate a fourth comparison signal;
• the logic controller is further configured to:
• receive the first comparison signal and the second comparison signal from the first transistor voltage-drop detector;
• receive the third comparison signal and the fourth comparison signal from the resistor voltage-drop detector;
• determine, based at least in part on the first comparison signal, the second comparison signal, the third comparison signal and the fourth comparison signal, whether or not a first fault related to the first transistor exists and whether or not a second fault related to the first resistor exists;
• and
• output, based at least in part on whether or not the first fault exists and whether or not the second fault exists, at least one or more control signals related to a limited power source protection for the power supply charger.

A method for a fast charging protocol controller of a power supply charger, the method comprising:

• detecting a first transistor voltage drop from a first drain of a first transistor to a first source of the first transistor to generate a first comparison signal and a second comparison signal, the first transistor being configured to provide an output current of the power supply charger and an output voltage of the power supply charger;
• detecting a resistor voltage drop from a first resistor terminal of a first resistor to a second resistor terminal of the first resistor to generate a third comparison signal and a fourth comparison signal, the first resistor being configured to receive a resistor current that is equal to the output current in magnitude;
• and
• outputting at least one or more control signals related to a limited power source protection for the power supply charger based at least in part on the first comparison signal, the second comparison signal, the third comparison signal, and the fourth comparison signal;
• wherein the detecting a first transistor voltage drop from a first drain of a first transistor to a first source of the first transistor to generate a first comparison signal and a second comparison signal includes:
• comparing the detected first transistor voltage drop with a first threshold voltage to generate the first comparison signal;
• and
• comparing the detected first transistor voltage drop with a second threshold voltage to generate the second comparison signal;
• wherein the detecting a resistor voltage drop from a first resistor terminal of a first resistor to a second resistor terminal of the first resistor to generate a third comparison signal and a fourth comparison signal includes:
• comparing the detected resistor voltage drop with a third threshold voltage to generate the third comparison signal;
• and
• comparing the detected resistor voltage drop with a fourth threshold voltage to generate the fourth comparison signal;
• wherein the outputting at least one or more control signals related to a limited power source protection for the power supply charger includes:
• receiving the first comparison signal, the second comparison signal, the third comparison signal and the fourth comparison signal;
• determining, based at least in part on the first comparison signal, the second comparison signal, the third comparison signal and the fourth comparison signal, whether or not a first fault related to the first transistor exists and whether or not a second fault related to the first resistor exists;
• and
• outputting, based at least in part on whether or not the first fault exists and whether or not the second fault exists, at least the one or more control signals related to the limited power source protection for the power supply charger.