Patent ID: 8111047

Claim:
A device including a system for recharging a battery at a port of the device comprising: a rechargeable battery; a thermistor associated with the rechargeable battery, the thermistor operable to vary its resistance in response to temperature of the rechargeable battery; a voltage clamping circuit in communication with the thermistor, the voltage clamping circuit comprising: a current source comprising a fixed current source and a variable current source, the current source configured to be in communication with the thermistor when the rechargeable battery is connected to the port; an amplifier configured to compare a sensor node voltage in communication with a voltage drop across the thermistor to a middle reference voltage between a low reference voltage indicative of the temperature of the rechargeable battery and a high reference voltage indicative of the rechargeable battery's being removed from the port, the amplifier configured and connected to provide a control output to control the variable current source to modify a current output from the variable current source to at least in part prevent the sensor node voltage from exceeding the middle reference voltage when the rechargeable battery is connected to the port.