Phase controlled regulated power supply

Claim 1

A phase-controlled power supply circuit for providing regulated dc power to a radiant energy-producing load, said power supply circuit adapted to compensate for the effects of rapid power fluctuations in the ac input line source, said circuit comprising: rectifier means for converting ac input voltage to full wave rectified dc voltage, means for generating a first output signal V c representative of the radiant energy emanating from said load, said generating means including a photosensing device which generates a current proportional to the radiant energy from the load impinging thereon, a first amplifier for converting said current into a voltage output V 2 and a second amplifier for amplifying output V 2 to generate output signal V c , means for comparing output V c with a portion of the rectified dc voltage to produce a second output V o , said comparing means comprising a third amplifier means for comparing the signal V c , received at the negative input of said third amplifier with a portion of the rectified dc voltage received at the positive input of said third amplifier, and a transistor switching circuit coupled between said comparing means and said load, said switching circuit being adapted to be turned on and off at a rate determined by the rate of change of the level of signal V o , whereby the load is turned on and off at a rate consistent with the switching circuit.