| 摘要 |
PURPOSE: To reduce power consumption by detecting the condition of control of the load of a DC generating means on the basis of a specified voltage value set beforehand, and stopping the control of a switching regulator only at the time of no load. CONSTITUTION: A rectified and smoothed AC power source 1 switched by a switching regulator 4 is inputted to the primary winding 51 of a transformer 5, and its secondary winding 52 sends out output voltage. On one side, flyback voltage generated with the tertiary winding 53 of the transformer 5 is rectified and smoothed, and by supplying the voltage the switching regulator 4 is controlled. On the other side, the output voltage of the secondary winding 52 is rectified and smoothed, and supplied to a load. Furthermore, a detecting means 8 which detects this load voltage, collates it with a voltage set beforehand, and learns the condition of connection of the load is provided, and control 31 of stopping the switching 4 only at the time of no load is performed. Consequently, it becomes possible to reduce wasteful power consumption. |
