Patent ID: 7592849

Claim:
A level shifter including a stage having a first branch and a second branch, each branch including: a selection terminal coupled to each branch for receiving a selection signal, the selection signal received by the first branch and the second branch being alternatively at a first voltage and at a second voltage higher than the first voltage in absolute value, a service terminal for receiving a third voltage higher than the second voltage in absolute value, an input circuit for electrically coupling an intermediate node to the selection terminal if the second voltage is detected at the selection terminal or for insulating the intermediate node from the selection terminal otherwise, an interface circuit for coupling an output terminal to the intermediate node if the second voltage is detected at the selection terminal or for insulating the output terminal from the intermediate node otherwise, and an output circuit for insulating the service terminal from the output terminal when coupled or for coupling the service terminal to the output terminal otherwise, the output terminals of the first branch and the second branch providing an output signal being alternatively at the second voltage or at the third voltage according to the selection signal.