Patent ID: 8710897

Claim:
A level shifter, comprising: a first-level shifter unit configured to convert an external input signal into a signal in a preset first-voltage range using a plurality of transistors and a first clamping power supply and output the converted signal; and a second-level shifter unit configured to convert the signal output from the first-level shifter unit into a signal in a preset second-voltage range using a plurality of transistors and a second clamping power supply and output the converted signal, wherein an upper-threshold voltage of the second-voltage range is higher than that of the first-voltage range and a lower-threshold voltage of the second-voltage range is higher than that of the first-voltage range, wherein, in each of the plurality of transistors in the first-level shifter unit and the plurality of transistors in the second-level shifter unit, a voltage between a gate and a source thereof is equal to or less than 6 V, and wherein the first clamping power supply is directly received by the gates of two of the plurality of transistors of the first-level shifter and configured to prevent the signal output of the first-level shifter unit from being lower than the lower-threshold voltage of the second-level shifter.