Method and apparatus for mode selection for high voltage integrated circuits

DETAILED DESCRIPTION Disclosed is a method to select alternative functional modes of operation of an integrated circuit through a terminal that can withstand a high maximum voltage.
In one embodiment, an integrated circuit includes a functional circuit coupled to a plurality of terminals including first, second and third terminals of the integrated circuit.
The first terminal is adapted to withstand a first maximum voltage relative to the second terminal while the third terminal is adapted to withstand a second maximum voltage relative to the second terminal.
The second maximum voltage is substantially greater than the first maximum voltage.
The integrated circuit also includes a detector circuit coupled to detect a voltage at the third terminal.
The detector circuit has a first state when the voltage at the third terminal is less than a first threshold and the detector has a second state when the voltage on the third terminal is greater than a second threshold.
The integrated circuit also includes a selector circuit coupled to the detector circuit and the functional circuit.
The selector circuit is adapted to select one of at least two distinct modes of operation for the functional circuit in response to the plurality of terminals.
Additional features and benefits of the present invention will become apparent from the detailed description, figures and claims set forth below.