A switching control circuit configured to control the switching of a step-up/step-down DC-DC converter by use of a step-down control signal and a step-up control signal, wherein, the switching control circuit comprises: a slope voltage generator configured to generate a first slope voltage and a second slope voltage that have opposite phases and that cross each other while said first slope voltage is increasing and said second slope voltage is decreasing between a peak value and a bottom value common to the first and second slope voltages (Vs1, Vs2); a first comparator configured to generate a first comparison signal by comparing the first slope voltage with a control voltage (Vc); a second comparator configured to generate a second comparison signal by comparing the second slope voltage with the control voltage (Vc); and a logic operator configured to generate the step-down control signal and the step-up control signal based on the first comparison signal and the second comparison signal, characterized in that the first slope voltage and the second slope voltage are both voltage signals having sawtooth waveforms, and wherein the slope voltage generator includes: a first current source connected between a first power terminal to which an input voltage (Vin) is applied and an output terminal from which the first slope voltage is output; a first capacitor connected between the output terminal from which the first slope voltage is output and a second power terminal to which a ground voltage (Vss) is applied; a second capacitor connected between a third power terminal to which a first reference voltage (Vref) is applied and an output terminal from which the second slope voltage is output; a second current source connected between the output terminal from which the second slope voltage is output and the second power terminal; a comparator configured to generate a reset signal by comparing the first slope voltage with the first reference voltage (Vref); a first discharge switch configured to discharge the first capacitor according to the reset signal; and a second discharge switch configured to discharge the second capacitor according to the reset signal. a slope voltage generator configured to generate a first slope voltage and a second slope voltage that have opposite phases and that cross each other while said first slope voltage is increasing and said second slope voltage is decreasing between a peak value and a bottom value common to the first and second slope voltages (Vs1, Vs2); a first comparator configured to generate a first comparison signal by comparing the first slope voltage with a control voltage (Vc); a second comparator configured to generate a second comparison signal by comparing the second slope voltage with the control voltage (Vc); and a logic operator configured to generate the step-down control signal and the step-up control signal based on the first comparison signal and the second comparison signal, characterized in that the first slope voltage and the second slope voltage are both voltage signals having sawtooth waveforms, and wherein the slope voltage generator includes: a first current source connected between a first power terminal to which an input voltage (Vin) is applied and an output terminal from which the first slope voltage is output; a first capacitor connected between the output terminal from which the first slope voltage is output and a second power terminal to which a ground voltage (Vss) is applied; a second capacitor connected between a third power terminal to which a first reference voltage (Vref) is applied and an output terminal from which the second slope voltage is output; a second current source connected between the output terminal from which the second slope voltage is output and the second power terminal; a comparator configured to generate a reset signal by comparing the first slope voltage with the first reference voltage (Vref); a first discharge switch configured to discharge the first capacitor according to the reset signal; and a second discharge switch configured to discharge the second capacitor according to the reset signal. a first current source connected between a first power terminal to which an input voltage (Vin) is applied and an output terminal from which the first slope voltage is output; a first capacitor connected between the output terminal from which the first slope voltage is output and a second power terminal to which a ground voltage (Vss) is applied; a second capacitor connected between a third power terminal to which a first reference voltage (Vref) is applied and an output terminal from which the second slope voltage is output; a second current source connected between the output terminal from which the second slope voltage is output and the second power terminal; a comparator configured to generate a reset signal by comparing the first slope voltage with the first reference voltage (Vref); a first discharge switch configured to discharge the first capacitor according to the reset signal; and a second discharge switch configured to discharge the second capacitor according to the reset signal.