| abstract |
A lamp control control circuit has triacs (16, 18) for controlling a current from an AC power supply (14) and supplying a controlled current to lamps (10, 12); a phase angle control unit (46) for generating phase angle control pulses for a soft start; switching controllers (20, 22) for triggering the triacs (16, 18) in response to phase angle control pulses, respectively; and switches (32, 34) for selecting the lamp (10, 12) which is to be energized. The control circuit has additional switches (42. 44) for detecting the lamp selecting operation of the switches (32, 34). The phase angle control unit (46) is started in response to a signal from those switches (42, 44). |