Patent ID: 8836305

Claim:
A DC/DC converter comprising: an input line via which a DC input voltage is to be supplied; an output line via which a load is to be connected; a switching transistor and a synchronous rectification transistor sequentially arranged in series between the input line and a ground line; an inductor having its one end connected to a switching node which is a connection node that connects the switching transistor and the synchronous rectification transistor, and having its another end connected to the output line; an output capacitor connected to the output line; and a control circuit configured to perform switching of the switching transistor and the synchronous rectification transistor, wherein the control circuit comprises: a pulse modulator configured to generate a pulse signal having a duty cycle adjusted such that a DC output voltage that develops at the output line matches a predetermined target voltage; a driver circuit configured to perform switching of the switching transistor and the synchronous rectification transistor according to the pulse signal; a first detection terminal connected to the switching node; a second detection terminal connected to the output line; a measurement circuit connected to the inductor via the first detection terminal and the second detection terminal, and configured to measure an inductance value and a DC resistance value of the inductor during calibration, before normal operation of the DC/DC converter; and a current detection circuit configured to detect, in normal operation, a current that flows through the inductor based upon a detection voltage that develops between the first detection terminal and the second detection terminal, using the inductance value and the DC resistance value thus measured.