| 摘要 |
A switching regulator includes a switching transistor to switch, an inductor to store charge from an input voltage, a comparator to compare a voltage at a connecting node of the switching transistor and the inductor with a predetermined voltage and generate a binary signal, a detector to detect a voltage difference between an output voltage and a predetermined reference voltage, a pulse generator to generate a pulse signal having a predetermined pulse width to switch the switching transistor on/off in VFM control mode, and a controller to determine the output voltage and select VFM or PWM control mode to make the output voltage a predetermined constant voltage. The controller changes the control mode from the VFM to the PWM control mode when the controller determines that the output voltage does not change while the pulse generator is outputting the pulse signal in the VFM control mode.
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