Solid State Light Source Driving and Dimming Using an AC Voltage Source

A solid state light source driving and dimming system, comprising:

• a plurality of solid state light source driver circuits configured to be coupled to an AC voltage source, each driver circuit comprising:
• constant current circuitry coupled to an AC voltage source, the constant current circuitry is configured to generate a constant AC current from the AC voltage source;
• isolation circuitry coupled to the AC voltage source and configured to electrically isolate each driver circuit from each other;
• rectifier circuitry coupled to the constant current circuitry and configured to generate a DC current to drive at least one solid state light source;
• shunt circuitry coupled to a negative and positive voltage rails of the AC voltage source;
• switch circuitry coupled to the shunt circuitry;
• and
• pulse width modulation (PWM) circuitry configured to generate a PWM signal to control a conduction station of the switch circuitry;
• wherein when the switch circuitry is closed, a conduction path exists between the AC voltage source and the shunt circuitry through the switch circuitry to discontinue the DC current, and when the switch circuitry is closed, the shunt circuitry is electrically decoupled from the AC voltage source.

A solid state light source driving and dimming system, comprising:

• an isolation transformer having a primary winding coupled to an AC voltage source and a plurality of secondary windings, wherein the isolation transformer is configured to electrically isolate each respective secondary winding from each other;
• a plurality of solid state light source driver circuits configured to be coupled to a respective secondary winding, each driver circuit comprising:
• constant current circuitry coupled to a secondary winding, the constant current circuitry is configured to generate a constant AC current from the AC voltage source;
• rectifier circuitry coupled to the constant current circuitry and configured to generate a DC current to drive at least one solid state light source;
• shunt circuitry coupled to a negative and positive voltage rails of the secondary winding;
• switch circuitry coupled to the shunt circuitry;
• and
• pulse width modulation (PWM) circuitry configured to generate a PWM signal to control a conduction station of the switch circuitry;
• wherein when the switch circuitry is closed, a conduction path exists between the secondary winding and the shunt circuitry through the switch circuitry to discontinue the DC current, and when the switch circuitry is closed, the shunt circuitry is electrically decoupled from the secondary winding.