Line-gated switching power supply

DETAILED DESCRIPTION The present invention relates to an improved power supply which avoids the disadvantages of prior power supplies while affording additional structural and operating advantages.
It is a general object of this invention to provide a power supply which will operate whether the AC source is continuous or intermittent, i.
e.
, removed for a portion of each AC cycle.
It is another object of this invention to provide a power supply of the type set forth which can effectively supply a varying load while having the relatively high efficiency of a switching-type regulator supply.
It is still another object of this invention to provide a power supply of the type set forth, which is operable with any frequency AC source.
Yet another object of the invention is the provision of a power supply of the type set forth which is characterized by small size and minimal heat generation.
Another object of this invention is the provision of a microprocessor-controlled lamp dimming circuit incorporating a power supply of the type set forth.
These and other objects of the invention are attained by providing a line gated switching power supply capable of operation with an interrupted AC source, the power supply comprising a charge storage device adapted to be connected across an associated load, current valve means connected in circuit between the associated AC source and the charge storage device and adapted for operation between an open-circuit condition and a maximum-conduction condition for passing maximum current to the charge storage device for charging same, means for providing a control current to the current valve means sufficient to operate the current valve means in its maximum-conduction condition, and control means coupled to the current valve means and responsive when the voltage across the charge storage device exceeds a predetermined level for removing the control current from the current valve means thereby to cause the current valve means to shift to its open-circuit condition and terminate current flow to the charge storage device