Patent ID: 8760074

Claim:
A tunable lighting system, comprising: a series connected string of a white light emitting semiconductor device and a first non-white color light emitting semiconductor device, the first non-white color of light being one of red, amber and orange; a first driver connected for applying a controllable drive current to the series connected string of light emitting semiconductor devices to drive the white light emitting semiconductor device and the first non-white color light emitting semiconductor device together in common; at least one second non-white color light emitting semiconductor device, the second non-white color of light being different from the first non-white color of light; a second driver connected for applying a controllable drive current to the at least one second non-white color light emitting semiconductor device; an input for receiving a user input relating to a selection of a spectral characteristic for a light output of the tunable lighting system; and a microcontroller having a first control channel output connected to control the first driver and a second control channel output connected to control the second driver, wherein the microcontroller is configured to selectively operate the drivers via the control channel outputs in response to the received user input to cause combined light from the white and non-white light emitting semiconductor devices to produce the selected spectral characteristic for the light output of the tunable lighting system.