Adjusting apparatus and adjustment method

An adjusting apparatus comprising:

• a capacitor that is charged by output current output from a switching power source circuit;
• a current source circuit that generates a current of an amount corresponding to a set designated value and causes the capacitor to be charged by the generated current;
• a switch that switches between charging of the capacitor by the current from the current source circuit and discharging of the capacitor;
• a first setting unit that sequentially sets the designated value for the current source circuit to be settable values;
• a first control unit that each time the first setting unit sets the designated value, causes the discharging of the capacitor to end by switching the switch to a discharging side when the capacitor is not charged by the output current;
• a second control unit that causes the capacitor to be charged by switching the switch to a charging side when the first control unit causes the discharging of the capacitor to end;
• a determining unit that determines whether a time period from a time when the second control unit switches the switch to the charging side until a time when an electric potential difference of the capacitor exceeds a threshold value is a predetermined time period;
• and
• a second setting unit that sets among the designated values set by the first setting unit, the designated value for the current source circuit to be a value for which the determining unit determines that the time period to exceed the threshold value is the predetermined time period.

An adjusting method of adjusting a designated value that sets a slope compensation circuit having a capacitor that is charged by output current output from a switching power source circuit;

• a current source circuit that generates a current of an amount corresponding to the set designated value, and causes the capacitor to be charged by the generated current;
• and a switch that switches between charging of the capacitor by the current from the current source circuit and discharging of the capacitor, the adjusting method comprising:
• setting the designated value for the current source circuit to be a predetermined value;
• causing the discharging of the capacitor to end by switching the switch to a discharging side when the capacitor is not charged by the output current;
• causing the capacitor to be charged by switching the switch to a charging side, after the discharging of the capacitor ends and the designated value is set;
• measuring a time period from a time when the second control unit switches the switch to the charging side until a time when an electric potential difference of the capacitor exceeds a threshold value;
• calculating based on the measured time period and the predetermined value, the designated value such that the time period measured at the measuring is a predetermined time period;
• and
• setting the designated value for the current source circuit to be the designated value calculated at the calculating unit.