Method and apparatus for sensing multiple voltage values from a single terminal of a power converter controller

A controller for use in a power converter, comprising:

• a sensor coupled to receive a signal from a single terminal of the controller, the signal from the single terminal to represent an output voltage of the power converter during at least a portion of an off time of a power switch and the signal from the single terminal to represent a line input voltage during at least a portion of an on time of the power switch;
• a switching control to be coupled to switch the power switch to regulate the output of the power converter in response to the sensor;
• and
• an output fault detector coupled between the sensor and the switching control, wherein the output fault detector is coupled to detect a fault condition in response to the signal representative of the output voltage of the power converter and to output a fault signal to the switching control in response to the detection of the fault condition.

A controller for use in a power converter, comprising:

• a sensor coupled to sample an input received at a single terminal of the controller during a portion of an off time of a power switch to output a signal representative of an output voltage of the power converter, the sensor further coupled to sense the input at the single terminal during at least a portion of an on time of the power switch to output a signal representative of a line input voltage of the power converter;
• a switching control to be coupled to switch the power switch to switch the power switch to control a transfer of energy from an input of the power converter to an output of the power converter;
• a power limiter coupled between the sensor and a switching control, the power limiter coupled to output a power limit signal to the switching control in response to the signal representative of the line input voltage of the power converter, wherein the switching control is further coupled to switch the power switch to control the transfer of energy from the input of the power converter to the output of the power converter in response to the power limit signal;
• and
• an output fault detector coupled between the sensor and the switching control, wherein the output fault detector is coupled to detect a fault condition in response to the signal representative of the output voltage of the power converter and to output a fault signal to the switching control in response to the detection of the fault condition.