An Efficient LED System-in-Module for General Lighting Applications

Investigating Organization
Philips Electronics North America Corporation

Principal Investigator(s)
Mr. Jim Gaines, Mr. Ron Steen

Subcontractor
Philips Lighting’s Corporate Calibration and Standards Lab

Funding Source
Building Technologies Program/NETL

Award
DOE Share: $1,567,276; Contractor Share: $1,044,851

Contract Period
01/15/05 - 11/14/08

Philips Lighting - Lighting Electronics NA, together with Philips Semiconductors and the Philips Corporate Calibration and Standards Lab, propose to develop multi-colored LED sources in which a single integrated package, containing multiple high power LED die, serves as a self-contained lamp module generating feedback-controlled light of user-selectable color and intensity. In addition to the LED die, the package will include first-stage optics for color mixing, optical and thermal feedback sensors, structures for thermal management, and drive and control electronics. The LED die will be close together to promote color mixing and to provide a compact source so that the package will deliver about as many lumens as current luminaires of the same exit surface area. The user will supply, via an intuitive interface, a control signal to specify lamp color and intensity. The user will not have to understand the intricacies of feedback control systems in order to use the resulting lighting system. The proposed system will be equipped to accept wireless links to remote controls and/or remote sensor signals (such as those from daylight sensors). We refer to this integrated LED multi-chip source system as an LED system-in-module (LED-SIM) and believe, based on our extensive manufacturing and commercial experience in lighting, that such an integrated system is critical for early market acceptance.  Developing this technology will require capabilities in optics, thermal management, electronics, silicon integration and system architecture. We expect the LED-SIM modular approach (and the general principles that will be derived) to provide a direct path to lamp systems useful in the majority of commercial lighting applications and some residential applications. However, for the purpose of this project, we limit the carrier to be LED-SIMs intended specifically for general lighting applications (non-accent), equivalent to reflector PAR (flood) systems and recessed CFL systems. The project is organized in three phases. Two of these are stages of increasing integration, and the last is to build the resulting LED-SIM into a flood lamp demonstrator. In the first phase, experimental RGBA white-light LED-SIMs will be designed and built with integrated LEDs, sensors, drive and control electronics, first stage optics, and thermal management. The electronics will be integrated in modules (e.g. controller, driver, memory chips, passive components, and user interface electronics). Minimization of lamp size is not a priority in this phase. The goal is to make a self-contained lamp module generating feedback-controlled light of user-selectable color and intensity, and requiring only line voltage input power and a signal defining the light color and intensity.  In the second phase, building on the first phase, the LED-SIM design will be finalized, by integrating the electronic functional blocks fully, incorporating optimized thermal management designs and incorporating improved optics. The size of the module will be minimized. A general output from this phase is a methodology for designing LED-SIMs that will be useable for various applications.  In the third phase, a prototype lamp system, sized to retrofit a PAR38 lamp, will be made, based on the LED-SIMs. The ultimate deliverable and the result of the third phase is a flood lamp with an intuitive user interface for color and intensity selection.

Relevant results achieved so far include: 1) An LED-SIM containing a commercially available 6-die multichip LED package and electronics designed using existing components. The LED-SIM corrects for variations in LED spectrum using temperature feedforward and intensity feedback. Intensity of each color of LEDs is measured independently with a photodiode.  2) An LED light source composed of 7, 9 or 16 closely-spaced LED die, with a reflector to shape the beam to that of a flood light. 3) Design/specification of an IC to integrate the electronics system. First ICs have been built, to test key portions of the electronics.

Content dated 2/08