| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a voltage generating circuit which can prevent an increase in an occupied area and is suitable for step-up of power supply voltages of a wide range, and to provide a control method thereof. <P>SOLUTION: The voltage generating circuit includes a first charge pump unit 10 for receiving an input first clock signal CLK 1 and generating a voltage V1 obtained by pumping the voltage of a first external power supply with a first voltage; a voltage selecting unit 40 for deciding to select the voltage V1 generated in the first charge pump unit 10 or a voltage V11 of a second external power supply on the basis of a voltage selection command signal CHN1; a level converting unit 22 for converting the voltage level of the first clock signal CLK1 into a second voltage level; and second charge pump units 20A, 20C for each receiving an input second clock signal CLK2 converted by the level converting unit 22 and generating voltages V2, V3 obtained by pumping the selected voltage V1 or the voltage V11 of the second external power supply in a second voltage step. <P>COPYRIGHT: (C)2008,JPO&INPIT</p> |
