摘要 |
In a switching regulator, when a control switching signal received from outside is indicating PWM control, a second reference voltage generating circuit outputs, as a second reference voltage, a voltage that is lower than the minimum voltage of an output voltage range of an error amplifying circuit, so that output signals from a comparator are fixed at a high level. When a control switching signal received from outside is indicating VFM control, the second reference voltage generating circuit adjusts the second reference voltage according to the voltage difference between an input voltage and an output voltage, because the optimum second reference voltage varies according to the voltage difference between the input voltage and the output voltage.
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