Patent ID: 6946904

Claim:
An apparatus, comprising: an over-voltage sense circuit that is arranged to monitor a sense signal on a data line and activate a disable signal when an over-voltage condition is detected on the data line; a selector circuit that is arranged to provide a selected voltage, wherein the selected voltage corresponds to the greater of a power supply voltage and the sense signal; and a driver circuit that is arranged to provide an output signal to the data line in response to an input signal when enabled, wherein the driver circuit is disabled when the disable signal is active, the driver circuit comprising: a transmission gate that is configured to transfer the input signal to a first node when the driver circuit is enabled; a first inverting logic circuit that is arranged to provide a second signal at a second node in response to a first signal from the first node when active, wherein the first inverting logic circuit is deactivated when the disable signal is active; a second inverting logic circuit that is arranged to provide the output signal to the data line in response to the second signal and the input signal when active, wherein the second inverting logic circuit is deactivated when the disable signal is active; a transistor that is configured to couple the sense signal to the second node when the sense signal exceeds the power supply voltage by a threshold voltage that is associated with the transistor; and a pull-up circuit that is configured to couple the power supply voltage to the first node when the disable signal is active.