GPTS, LLC » Uncategorized

LED Lighting Lighting Facts

Gavin — Wed, 24 Aug 2011 20:30:13 +0000

Seminar for US Green Building Council – St Louis chapter went very well yesterday. Guess I should have posted a link to it before the event. But it was a full house anyway. Thanks Hope for organizing the event and Color Arts for hosting.

Driving offline LEDs

Gavin — Mon, 04 Jul 2011 20:54:25 +0000

Why do they call it offline? You are getting power off the power line? I would think this would be on-line.

Anyway, the problem is ow to get good efficiency, power factor,and low cost in a driver that can take as input 90VAC-300VAC so it will work world wide, and output DC power, current controlled, voltage limited, able to withstand transients, overheating etc.

As with any design, what started out as a big box of parts is heading towards a single chips solution, with some passives (LRC) around it. So how few and how small are the passive components in your design? Minimize inductors first, they are the most expensive. How small can you get a 5-20W supply? It needs to fit in a lamp base until we get the last hundred years of Edison fixtures replaced.

Oh, and what about dimming? Does your PS-CC solution allow for triac controlled dimming? Those triacs are nasty to power factor, but I have an answer! Send me an e-mail if you are interested. — gavin at this site.

Color Rendering Index vs. Color Quality Scale

Gavin — Thu, 14 Apr 2011 02:18:34 +0000

I’ve been working on LED lighting a lot lately. The field is still moving fast. Here’s a link for understanding CQS, my latest TLA (Three Letter Acronym)

http://www.nist.gov/pml/div685/grp05/vision_color.cfm

“A Color Quality Scale (CQS) is being developed at NIST with input from the lighting industry and the CIE (International Commission on Illumination) to address the problems of the CIE Color Rendering Index (CRI) for solid-state light sources… It will then be proposed as a new international standard.”

Progress

Gavin — Wed, 31 Mar 2010 08:24:05 +0000

Rochester project for Cephalogics is moving along nicely. SO yes, I’m too busy to blog.

Introductions

admin — Sat, 30 Jan 2010 23:37:57 +0000

Hi I’m Gavin and this is my new web site for my electronics design business GPTS, LLC.

I do a little of everything from PCB design to FPGA to embedded system programming.

Altium Designer is a great tool that lets you do it all, I just got the new version in Dec ‘09.

Enjoy the default content, hopefully I’ll be too busy to update this very much.