Patent ID: 8207722

Claim:
A boost DC/DC converter comprising: an input terminal that receives an input voltage; an output terminal that outputs an output voltage; an inductor having a first end connected to the input terminal; a switching transistor connected between a second end of the inductor and a ground; a diode having an anode connected to the second end of the inductor and a cathode connected to the output terminal; a capacitor connected between the output terminal and the ground; a voltage dividing circuit connected between the output terminal and the ground, that outputs a divided voltage obtained by dividing the output voltage; a reference voltage generating circuit that generates a reference voltage based on the input voltage; an error amplifier that receives the divided voltage and the reference voltage and outputs a first signal corresponding to the difference between the divided voltage and the reference voltage; a feedforward circuit that detects the input voltage and outputs a second Signal corresponding to a current inversely proportional to the input voltage; a multiplier that multiples ‘the first signal by the second Signal and outputs a third signal obtained; and a control circuit that outputs, based on the third signal, a control signal for controlling on/off of the switching transistor so that the divided voltage is equal to the reference voltage.