Patent ID: 7550981

Claim:
A method of determining wiper resistance of a potentiometer including a first terminal, a second terminal, a third terminal, a resistive element having a potentiometer resistance electrically coupled between the first and second terminals, and a wiper electrically coupled between the resistive element and the third terminal and movable to a wiper position between the first and second terminals, the method comprising the steps of: electrically energizing the potentiometer; electrically coupling a sense resistor to the potentiometer third terminal, the sense resistor having a substantially constant sense resistance; determining a potentiometer voltage, the potentiometer voltage being a voltage potential between the potentiometer first and second terminals; determining the wiper position based at least in part on the determined potentiometer voltage; electrically coupling the sense resistor to a potential that causes a wiper current to flow through the wiper and sense resistor; determining a magnitude of the wiper current; and determining the wiper resistance based at least in part on the potentiometer resistance, the determined potentiometer position, the determined wiper current magnitude, and the sense resistance.