Patent ID: 8076914
Filing Date: 2011-12-13
Classification: H02M

Abstract:
1. A switching regulator, comprising: a step-down-and-step-up unit configured to convert an input voltage to a low voltage that is lower than the input voltage or to a high voltage that is higher than the input voltage in accordance with a control signal; and a controller including a low-pass filter to receive a reference voltage generated in accordance with an external control signal and configured to cause the step-down-and-step-up unit to perform a step-down operation or a step-up operation in accordance with a voltage difference between a proportional voltage proportional to an output voltage of the step-down-and-step-up unit and the reference voltage, the controller causing the step-down-and-step-up unit to perform a step-down operation or a step-up operation in accordance with a voltage difference between an output voltage of the low-pass filter and the proportional voltage, and changing a time constant of the low-pass filter in accordance with the operation being performed, wherein the controller changes the time constant of the low-pass filter so that a time constant of the low-pass filter at a step-up operation is larger than a time constant of the low-pass filter at a step-down operation.