DC-DC converter and method of controlling DC-DC converter

摘要

A DC-DC converter includes a drive circuit configured to drive a first switching element, and a second switching element coupled between a low potential power terminal of the drive circuit and a first node corresponding to the input voltage or the output voltage. A current detecting section detects a load current flowing in the output terminal. A control circuit turns on a third switching element, which is coupled between the low potential power terminal of the drive circuit and a second node having a potential lower than both the input voltage and the output voltage, in a case where a difference between the input voltage and the output voltage is lower than a threshold. The control circuit controls the second and third switching elements based on a detection result of the current detecting section in a case where the difference is equal to or greater than the threshold.

主权项

1. A DC-DC converter that converts an input voltage to an output voltage, the DC-DC converter comprising:
a first switching element; a drive circuit coupled to the first switching element and configured to drive the first switching element so as to convert the input voltage to the output voltage; a second switching element coupled between a low potential power terminal of the drive circuit and a first node corresponding to the input voltage or the output voltage; a third switching element coupled between the low potential power terminal of the drive circuit and a second node having a potential lower than both the input voltage and the output voltage; a current detecting section configured to detect a load current flowing in an output terminal of the DC-DC converter; and a control circuit configured to turn on the third switching element in a case where a difference between the input voltage and the output voltage is lower than a threshold, and to control the second switching element and the third switching element based on a detection result of the current detecting section in a case where the difference is equal to or greater than the threshold.