A level shifter includes a first terminal configured to receive a first supply voltage, a second terminal configured to receive a second supply voltage, an input terminal configured to receive an input signal and an output terminal. The level shifter is configured to shift the input signal from the level of the first supply voltage to the level of the second supply voltage in outputting the output signal. The level shifter includes a storage circuit for storing the output signal value and configured, when the first supply voltage is no longer available, to force the output terminal to assume the last output voltage value stored by the storage circuit when the first supply voltage was available and before the first supply voltage was not available.