Abstract: A lighting apparatus includes: first, second and third groups of solid state light emitters; a first group of lumiphors; at least first, second and third power lines, the first, second and third group of solid state light emitters each being electrically coupled to at least one of the first, second and third power lines. A current controller controls the relative flux ratios of the first, second and third groups, the controller being programmed to, in response to receipt of a command, retrieve a set of data from a look-up table that contains information of the required flux output of each group of LEDs and generate pulse width modulation (PWM) signals to control current supplied to each group to alter the flux output of each group in order to achieve a desired CCT and total flux output.

Abstract: A lighting apparatus includes: first, second and third groups of solid state light emitters; a first group of lumiphors; at least first, second and third power lines, the first, second and third group of solid state light emitters each being electrically coupled to at least one of the first, second and third power lines. A current controller controls the relative flux ratios of the first, second and third groups, the controller being programmed to, in response to receipt of a command, retrieve a set of data from a look-up table that contains information of the required flux output of each group of LEDs and generate pulse width modulation (PWM) signals to control current supplied to each group to alter the flux output of each group in order to achieve a desired CCT and total flux output.