Voltage regulator for line powered linear and switching power supply

A low voltage power supply source for incandescent lamps, lamp loads, LED arrays, and LED array loads providing a low voltage within a range from 11.0 to 12.5 V AC comprising a voltage regulator circuit to provide a linear output response to input power variations and load changes of said low voltage power supply source, and to keep said low voltage power supply source further voltage output constant within the range from 11.0 to 12.5 V AC, said low voltage power supply source comprising, in combination:

• an AC power source means comprising mains power line of a 115 V AC to 480 V AC power line supply source and a step-down transformer thereof;
• wherein said voltage regulator means circuit senses output voltage of said transformer of said power line supply source, measures said output voltage against an internal DC reference voltage, operates to reduce the output voltage output of said transformer to match the internal DC reference voltage by reducing input power line voltage to said transformer and operates to limit inrush currents experienced by said power supply source to reduce thermal shock to lamp filaments of the incandescent lamps or lamp loads, and LED arrays or LED array loads in operation;
• and wherein the voltage regulator circuit comprises:
• a voltage sensing circuit for sensing the output of said step-down transformer comprising a full-wave bridge rectifier circuit to provide a pulsing DC voltage, a spike filter capacitor and a filter capacitor to suppress ripple currents;
• a soft-start lamp filament voltage equalizing oscillator circuit to limit inrush currents, said soft-start lamp filament voltage equalizing oscillator circuit connected to a pulsing DC voltage output of said full-wave bridge rectifier circuit of said voltage sensing circuit, said soft-start lamp filament voltage equalizing oscillator circuit comprising a zener diode and a capacitor;
• a DC voltage reference oscillator circuit for providing a DC voltage reference level across output of said soft-start oscillator circuit comprising a zener diode, a transistor, and a current limiter network of two resistors to provide an oscillation process wherein oscillation frequency is per values of said zener diode, said current limiter network of two resistors and said transistor to control conduction of an AC power line supply control triac circuit within predetermined voltage level ranges;
• and
• an AC mains power line supply control circuit for regulating voltage output of said 115V AC to 480 V AC power supply, said AC mains power line supply control circuit configured across said DC voltage reference oscillator circuit comprising said AC power line supply control triac circuit, an opto-isolator triac driver being coupled between a pulsing DC voltage level output of said DC voltage reference oscillator circuit and an AC voltage level input of said AC power source means, a capacitor to initiate conduction of said AC power line control supply triac circuit at start-up, and a resistor to limit current applied to said AC line control triac circuit.