A modular system includes an LED driver and an LED light engine. The driver includes a switched mode power converter and a first control unit to control a switch of the converter, thereby controlling the supply current to an LED assembly of the light engine. The assembly includes LEDs and one or more switches arranged in series or in parallel with one or more of the LEDs. The light engine also includes a second control unit controlling the one or more switches of the LED assembly so as to control current through the LEDs. The first control unit controls amplitude of the supply current. The second control unit controls duty cycle of the LED current through the LEDs. The first and second control units are configured to synchronize a switching operation of the switched mode power converter with a switching operation of the switches of the light engine.