high power led circut design

Hello! I apologize for the delay in potentially awarding a project, as we are still working through a lot of mechanical design and feasibility studies. I am messaging you to outline some more detail in terms of the scope I am looking to have done. We are developing a new bicycle headlight that focuses on highly efficient optics, efficient power control and low power draw. Most bike lamps on the market now use inefficient optics that wastes a lot of light energy, which in turn causes unnecessarily high lumen counts, which draws more power. Poor thermal design also increases the junction temperature of the LED, causing lumen loss and higher power draw. I am a mechanical and optical design engineer by trade, I do automotive optical design and product development for the aftermarket. But I do not have much skills in the way of electrical design. :) These are the features that I am looking to incorporate. 16850 Lithium Ion Batteries 5x Lumileds Luxeon ZES chips, or potentially an Oslon Black Flat 1x3 or 1x4 chip. Individually controlled for selective dimming. Each ZES chip can do around 300 lumens, but with them that close together, would be a more realistic 250 lumens. At ideal conditions the lumen per watt is around 125 Lm/W. I am aiming for around 10-11W at maximum power draw. This will generate more than enough lumens, combined with my optical design, to outperform anything on the market. Ideally PWM control, with thermistors and current sensing to detect whether the chips are getting too hot (and pull back the power gently so the user cannot detect it), or so that when lower battery life is detected it can slowly ramp down the output to keep the light running without user interference to step down in power. Ideally these ramps would be over the course of a minute or two so when the light is being used, the user will be very hard pressed to discern a 20-30% power reduction. 5 color chips to act as a “fuel gauge” to show battery life, as well as what brightness mode it is in when the user is pressing a button to change from low, medium, medium high, high, and flashing mode. With the dimming, I don’t wish to do an overall dimming level. The optic is designed so that there is one central chip, and two flanking it on either side. “Low” is just the center chip, delivering 300 lumens at less than 2-3W power draw. This should provide 10-15 hours of runtime. Medium would be the low chip at full power, and two more chips at 75% power. Medium High would be 3 chips at full power, and two outside ones at 25% power. Then high being all 5 chips at full brightness. Flashing would be just the center chip on a flashing sequence to be used as a daytime running light. Single press switch on the top of the device that will have a silicone button. What I am looking for from the engineer assigned to this project: Complete design from a PCB shape and STP files of the surrounding area given to you. Help in sourcing components and potential suppliers for PCB manufacturing and SMT production (This may be something I’ll be able to cover as well) Working demo (we will pay for any prototyping and component costs) Support in adjusting programming and fine tuning the device after engineering samples have come in. Validation that engineering samples meet the electrical requirements that you will develop I am hoping to forge a strong relationship with a very skilled engineer. We have several products in the works that I’d like to pursue, so if this product is done very well, future work will be sure to come! Please let me know if you have any questions, if this changes your potential schedule (at least for initial design to be complete, semi-prototyped, and sent to suppliers) , or if this is considered to be too much work for you. We are looking to launch our product by October/November. Thank you! Matthew Conte Co-Founder & CEO [login to view URL]