| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a power supply controller in which the lifetime of a battery can be prolonged. <P>SOLUTION: When the battery voltage is 2.2 V or above, battery voltage is applied to a step-down DC/DC converter 50e. Consequently, the load on a step-up DC/DC converter 50b and thereby power consumption thereof is reduced. When the battery voltage drops below 2.2 V, a step-up voltage is applied to the step-down DC/DC converter 50e. Consequently, operation of the step-down DC/DC converter 50e is assured even if the battery voltage is lower than 2.2 V at which the step-down DC/DC converter 50e operates. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
