| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a power supply controller capable of improving the accuracy of an output voltage independently of ripples of the output voltage, and to provide an electronic device and a method of controlling a power supply. <P>SOLUTION: A switching power supply control circuit 11 has an offset control amplifier 2, an offset control circuit 3, and a comparator ErrCMP. The offset control circuit 3 gives an offset by which a voltage value is reduced with the lapse of time to the comparator ErrCMP as an offset control signal by using an offset by which a feedback voltage Vfb instructing to supply a power becomes larger than a reference voltage Vref to obtain a low voltage as an initial value, during a time period after termination of supplying a power. The offset control signal facilitates the time change of the offset more as a difference between a direct-current component obtained by averaging the feedback voltage Vfb and the reference voltage Vref becomes larger, depending on a control signal Vamp output from the offset control amplifier 2. <P>COPYRIGHT: (C)2012,JPO&INPIT |
