Patent ID: 7782113
Filing Date: 2010-08-24
Classification: H03K

Abstract:
1. A level shifter comprising: a preliminary level-shifting circuit for receiving an input signal having a first operating voltage swing and converting the input signal into a first output signal and a second output signal both having a second operating voltage swing based on a first supply voltage and a second supply voltage, the first output signal and the second output signal having opposite voltage levels relative to each other; and an output auxiliary circuit, electrically coupled to the preliminary level-shifting circuit, for retaining the first output signal and the second output signal, the output auxiliary circuit comprising: wherein when the first output signal holds a high voltage level and the second output signal holds a low voltage level, if the first supply voltage is turned off, the output auxiliary circuit assists the preliminary level-shifting circuit in retaining the high voltage level of the first output signal based on the second supply voltage, and the output auxiliary circuit retains the low voltage level of the second output signal based on the high voltage level of the first output signal.