CONSTANT CURRENT POWER SUPPLY DEVICE

PROBLEM TO BE SOLVED: To provide a constant current power supply device with series regulator control system which achieves downsizing of the device, reduces the manufacturing cost, and improves the efficiency of current control.SOLUTION: A power supply 2 comprises a variable constant voltage power supply 2a and a constant voltage power supply 2b. The output voltage of the variable constant voltage power supply 2a is controlled so that a load voltage of a linear control element 3a included in an output current control circuit 3, detected by a load voltage feedback circuit 4a included in a load voltage control circuit 4 is a set load voltage value of the load voltage control circuit 4. This suppresses heat generation of the control element to achieve downsizing of the device and reduce the manufacturing cost, and allows an optimal current supply to the constant voltage load to achieve higher current control efficiency and reduced ripple current.