Portable device battery charging circuits and methods

A method, comprising:

• receiving electrical power at a connector of a portable device;
• charging a battery of the portable device from the electrical power with a charge current having an initial value;
• monitoring a voltage at the connector while increasing the charge current above the initial value;
• in response to the voltage at the connector dropping below a predetermined value at an increased charge current, setting a charge current limit to a value less than the increased charge current corresponding to the voltage drop;
• and
• limiting a maximum charge current according to the charge current limit while charging the battery with the electrical power from the connector.

A method, comprising:

• setting a charge current received at a connector of a portable device to an initial charge current value;
• determining a voltage at the connector while increasing the charge current;
• determining a maximum charge current value based on whether the voltage at the connector drops below a predetermined limit as the charge current is increased;
• and
• selectively disabling application circuits of the portable device based on a predetermined priority in response to the maximum charge current value.