POWER SUPPLY DEVICE, LIGHTING DEVICE FOR DISCHARGE LAMP AND ILLUMINATION DEVICE

摘要

PURPOSE:To prevent a control circuit from erroneously operating due to currents flowing through a circuit. CONSTITUTION:In a discharge lamp lighting device 1, a main circuit portion 2 that constitutes an inverter is provided in a section 3 on a substrate and a control circuit portion 4 including an IC 16 is provided in a section 5. Further, in the discharge lamp lighting device 1, an IC stabilized potential line 25 of the control circuit portion 4 is branched off from a main circuit stabilized potential line 23 of the main circuit portion 2. An IC high potential line 15 is connected to a power supply high potential input terminal Vdd of the IC 16. The IC stabilized potential line 25 is connected to a stabilized potential terminal GRD of the IC 16. An output terminal Out of the IC 16 is connected to the gate of an FET 18 of the main circuit portion 2. With this constitution, a magnetic field applied to the control circuit portion 4 including the IC 16 can be suppressed to a low level because magnetic fields generated by a main circuit high potential line 13 and the IC stabilized potential line 25 counteract a magnetic field generated by the main circuit stabilized potential line 23. As a result, erroneous operation of the control circuit portion 4 including the IC 16 can be prevented.