A power supply circuit having an input configured to be coupled to a battery, the power supply circuit comprising: a pulse width modulator, PWM, configured to output a PWM signal in accordance with a difference between an output voltage (Vout) of the power supply circuit and a target voltage (Vref); a switch coupled to the input and configured to receive a battery voltage (Vin), the switch further being configured to be controlled by the PWM signal output from the PWM; a voltage feedback controller; a variable-type current feedback controller, configured such that its characteristic can be changed in accordance with a first parameter, the first parameter being settable to the current feedback controller, the characteristic being a gain-frequency characteristic of the current feedback controller in an open loop state, the first parameter including a parameter by which a gain is defined and a parameter by which a phase is defined, the current feedback controller being configured to supply to the PWM a signal that is adjusted in accordance with the two parameters of the first parameter; and a parameter controller (10, 10A, 10B) including a table in which a plurality of different values of the first parameter together with corresponding battery voltage ranges, and load current ranges are stored in an associated manner, wherein the parameter controller is configured, in accordance with a battery detection signal on the basis of the battery voltage (Vin) supplied to the switch and a current detection signal on the basis of a current output through the switch, to select one of the values of the first parameter when it is determined that the battery voltage (Vin) and a load current output from the power supply circuit fall within a battery voltage range and within a load current range, respectively, with which said value of the first parameter is associated, and the parameter controller (10, 10A, 10B) is further configured to set the selected value of the first parameter to the current feedback controller, thereby changing the gain-frequency characteristic of the current feedback controller. a pulse width modulator, PWM, configured to output a PWM signal in accordance with a difference between an output voltage (Vout) of the power supply circuit and a target voltage (Vref); a switch coupled to the input and configured to receive a battery voltage (Vin), the switch further being configured to be controlled by the PWM signal output from the PWM; a voltage feedback controller; a variable-type current feedback controller, configured such that its characteristic can be changed in accordance with a first parameter, the first parameter being settable to the current feedback controller, the characteristic being a gain-frequency characteristic of the current feedback controller in an open loop state, the first parameter including a parameter by which a gain is defined and a parameter by which a phase is defined, the current feedback controller being configured to supply to the PWM a signal that is adjusted in accordance with the two parameters of the first parameter; and a parameter controller (10, 10A, 10B) including a table in which a plurality of different values of the first parameter together with corresponding battery voltage ranges, and load current ranges are stored in an associated manner, wherein the parameter controller is configured, in accordance with a battery detection signal on the basis of the battery voltage (Vin) supplied to the switch and a current detection signal on the basis of a current output through the switch, to select one of the values of the first parameter when it is determined that the battery voltage (Vin) and a load current output from the power supply circuit fall within a battery voltage range and within a load current range, respectively, with which said value of the first parameter is associated, and the parameter controller (10, 10A, 10B) is further configured to set the selected value of the first parameter to the current feedback controller, thereby changing the gain-frequency characteristic of the current feedback controller.