Mood Globe lighting demonstrator
The Mood Globe shows a new lighting trend using super High Brightness RGB LEDs. Thanks to an electronic driving system, it is easy to implement many different lighting features like soft automatic colour change, manual colour setting including a bright white, brightness regulation or other attractive light effects.
Therefore, such advanced lighting systems become more and more popular and widely used in the mood lighting and architainment lighting market.
The lighting Mood Globe is designed in order to demonstrate an approach, how fashionable RGB LED lighting systems can be designed, regarding electrical, optical and thermal point of view. The heart of this application is an OSRAM OSTAR Projection or OSRAM OSTAR Lighting RGGB LED and a ST driver circuit solution consisting of few Integrated Circuits (ICs). A small 8-bit microcontroller ST7FLITE09, provides all lighting features and protects the LED against over temperature. The constant current sources are used for each individual LED in order to guarantee their proper function. The maximum LED current is set to 700mA using 2 STP04CM05 devices (four channel constant current sources with shift register and SPI interface). The brightness is controlled by software PWM signals. Thanks to the microcontroller, it is very easy to implement new lighting features or modify the design exactly following customer's request and specification.
This application is designed for a wide DC-input voltage range, 7V to 18V, using a high efficient (above 90%) and high power (4V/3A) step down DC/DC converter ST1S10. The microcontroller is using the NTC provided on the OSRAM OSTAR Projection module in order to measure the LED temperature and protect them against overheating. It is possible to order the whole electronic system designed in the Mood Globe, including board driver and OSRAM high power RGB LEDs. STEVAL-ILL009V5 is the driver motherboard and STEVAL-ILL009V3 is the module with high power RGB LED (OSRAM OSTAR projection module) and heatsink. All design steps and calculations are described in the application note AN2531, which can be found on www.stmicroelectronics.com
The heatsink has an arrangement and number of pins for optimum air flow. It is suitable for forced and free convection. Excellent thermal conductivity is ensured by the alloy material Al 99.5, 220W/mk. A constant heat distribution in the base and the pins is provided in the direction of heat flow.
It has low weight achieved by optimised geometry. Fixing clamp, thermally conductive adhesive foil or thermally conductive glue allows easy mounting.
Optical and light consulting / Light Architecture
Heatsink engineering and manufacturing, Thermal management substrates, Thermal interface materials
Electronic and Controls Engineering, Electronics Manufacturing Services (EMS), IC driver manufacturers, Driver Circuit Supplier