| 摘要 |
PROBLEM TO BE SOLVED: To efficiently improve precision of various drive voltage waveforms while suppressing power consumption.SOLUTION: After a plurality of first electricity storage elements are charged with a first voltage, the number of first storage elements connected in series is changed so as to generate a staircase voltage waveform which varies in voltage in steps. The staircase voltage waveform is bottomed up by a second voltage generated by a second electricity storage element so as to generate a drive voltage waveform. At this time, the first voltage and second voltage can be changed according to the drive voltage waveform. Consequently, a drive voltage waveform having high voltage resolution can be generated by suitably changing the first voltage and second voltage according to the drive voltage waveform to be generated. Further, first electricity storage elements which are mounted can be all utilized so as to eliminate the need to unnecessarily increase the total number of the first electricity storage elements and also to avoid problems of an increase in circuit size and a rise in manufacturing cost. |
