Patent ID: 7511651

Claim:
A switching interface for a first receiver, a second receiver, and a resistor ladder, comprising: a first terminal coupled to a first resistor of the resistor ladder; a second terminal coupled to the first resistor; a third terminal coupled to a reference voltage; a switch having a first state coupling the first terminal to the third terminal and a second state coupling the second terminal to the third terminal; a first analog-to-digital (A/D) converter coupled to the resistor ladder and the first receiver, the first A/D configured to compare a first voltage with a second voltage to determine if the switch is positioned in the first state or the second state; and a second analog-to-digital (A/D) converter coupled to the resistor ladder and the second receiver, the second A/D configured to compare the first voltage with the second voltage to determine if the switch is positioned in the first state or the second state.