| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a switching power supply circuit which can restrict an error in output voltage without increasing gain G. <P>SOLUTION: A switching power supply circuit 40A comprises: a reference power supply 43 which generates partial resistances R42H and R42L with which a secondary voltage Vout is divided and a reference voltage Vref; an error amplifier 44 which has the reference voltage Vref fed into its subtraction input terminal and a divided secondary voltage Vout fed into its inverse input terminal and also has its output terminal connected to the inverse input terminal via a feedback resistor R44; and a cancellation circuit 90 which is an output voltage error correction circuit. In order to correct a signal error at the output terminal of the error amplifier 44 caused by a feedback current Ifb flowing in the feedback resistor R44, the cancellation circuit 90 pulls in a current equal to the feedback current Ifb. <P>COPYRIGHT: (C)2013,JPO&INPIT |
