Pin determination for single-conductor interface systems and methods

A system for defining functionality of pins, the system comprising:

• transmission gate circuits configured to monitor inputs from a first pin and a second pin, wherein the first pin and the second pin are swappable pins;
• a power-on-reset (POR) circuit configured to detect when a supply voltage crosses a POR threshold;
• and
• a first latch circuit configured to:
• activate when the supply voltage crosses the POR threshold;
• determine whether a first signal corresponding to the first pin is higher than a second signal corresponding to the second pin;
• and
• define functions of the first pin and the second pin based on the determination.

A method for defining functionality of pins, the method comprising:

• monitoring inputs from a first pin and a second pin;
• identifying a first signal and a second signal from the inputs when a supply voltage crosses a power-on-reset (POR) threshold, wherein the first signal corresponds to the first pin and the second signal corresponds to the second pin;
• determining whether the first signal corresponding to the first pin is higher than the second signal corresponding to the second pin;
• and
• defining functions of the first pin and the second pin based on the determining.

A chip, comprising:

• a first pin;
• a second pin;
• and
• a circuit configured to:
• monitor respective inputs from the first pin and the second pin, wherein the first pin and the second pin are swappable pins configured to perform a first function or a second function;
• detect when a supply voltage crosses a POR threshold;
• and
• once the supply voltage crosses the POR threshold:
• determine whether a first signal corresponding to the first pin is higher than a second signal corresponding to the second pin, wherein the first signal and the second signal are based on the respective inputs;
• and
• define functions of the first pin and the second pin based on the determination, wherein the functions are the first function and the second function.