| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To stabilize boosting time regardless of the weight of a load. <P>SOLUTION: A power supply circuit (30) includes: a charge pump circuit (31); a determination circuit (32) and a control circuit (33). The charge pump circuit boosts input voltage (Vcc). The determination circuit determines whether boosted voltage (Vpp) output from the charge pump circuit reaches targeted voltage (VppA, VPPB) or not. The control circuit feedback-controls a boosting operation by the charge pump circuit. When the boosted voltage does not reach the targeted voltage within a predetermined time, the targeted voltage is updated by increasing the boosting capability of the charge pump circuit. Once the boosted voltage reaches the targeted voltage within the predetermined time, the targeted voltage is updated without changing the boosting capability. <P>COPYRIGHT: (C)2008,JPO&INPIT</p> |
