Patent ID: 8159269
Filing Date: 2012-04-17
Classification: H03K

Abstract:
1. An integrated circuit comprising: a terminal; and a circuit that determines whether the terminal is coupled external to the integrated circuit by a low impedance to a voltage source, or whether the terminal is coupled external to the integrated circuit by a medium impedance to the voltage source, or whether the terminal is floating or substantially floating, wherein a voltage on the terminal is lower than a first threshold voltage but higher than a second threshold voltage when the terminal is coupled by the medium impedance to the voltage source, wherein the circuit asserts a first digital logic signal if the circuit determines that the terminal is coupled by the low impedance to the voltage source, wherein the circuit asserts a second digital logic signal if the circuit determines that the terminal is coupled by the medium impedance to the voltage source, and wherein the circuit asserts a third digital logic signal if the circuit determines that the terminal is floating or substantially floating.