Hybrid dimming control techniques for lighting drivers

Techniques are disclosed for independent control of individual LED strings driven from a single AC current source. A lighting driver circuit includes a DC-AC inverter with series resonance that provides a current that may be split into multiple currents for driving multiple LED assemblies (LED1, LED2, LED3). Current splitting transformers (T1, T2, T3) may be used to divide the current from the AC source, and the amplitude of the current from the AC source may be determined by a microcontroller. In some cases the current splitting transformers provide galvanic isolation to the LED assemblies. The multiple LED assemblies may be controlled by a number of switches (S1, S2, S3) that may independently activate the individual LED assemblies based on the duty cycle of multiple PWM signals provided to the switches by the microcontroller. When all of the PWM signals output from the microcontroller are in an off-cycle, the current source may be turned off.