Patent ID: 8730146

Claim:
A drive voltage generating circuit comprising: a first shifter receiving an input voltage, first shifting a voltage level of the input voltage, and outputting a first drive voltage; a second shifter second shifting a voltage level of the first drive voltage and outputting a second drive voltage; and a drive voltage controller adjusting one of a shifting amount of the first shifter and a shifting amount of the second shifter in accordance with a surrounding temperature, wherein the second drive voltage is continuously varied in relation to changes in the surrounding temperature, wherein a voltage level of the second drive voltage is substantially in an inverse proportion to a change of the surrounding temperature, and wherein the second drive voltage has a first voltage level in a first region where the surrounding temperature is high, a second voltage level that is higher than the first voltage level in a second region where the surrounding temperature is low, and a voltage level that continuously increases from the first voltage level to the second voltage level in accordance with the temperature decrease in a third region between the first region and the second region.