Driving a High Lumen LED cost effectively - Page 1
Forum section: electronics / beginners

author: desai_amogh
author_rank: Contributor
timestamp: February 18, 2014, 01:58:13 pm
content: Hi,Can we drive this kind of High Lumen LEDs without a Voltage Booster IC??http://in.rsdelivers.com/product/osram-opto-semiconductors/gw-p9lrs1em-pqps-40s7/duris-s8-led-white-4000k-7-step/7916924.aspxFor example directly through mains (230v) using a DC regulated power supply ??Its Forward Voltage is 26.6 and Forward current 10mA to 240mAI am actually trying to find a cheaper way to drive High lumen LEDs. I'd welcome other ideas around this !Thanks-Amogh

author: tszaboo
author_rank: Super Contributor
timestamp: February 18, 2014, 04:11:59 pm
content: You rectify the mains. Than you stack up enough of them so the linear regulator doesn't dissipate more than few watts. Than you find those current regulator two terminal diodes from ON Semiconductor, so you parallel the correct number of them. Something like NSIC2020BT3G. Done.

author: Corporate666
author_rank: Unknown
timestamp: February 18, 2014, 10:36:39 pm
content: Quote from: desai_amogh on February 18, 2014, 01:58:13 pmSure you can drive it through a mains-powered DC regulated supply. When starting with mains and rectifying, you can output DC at whatever level you like either with a correctly sized transformer and/or a buck regulator.

author: desai_amogh
author_rank: Contributor
timestamp: February 19, 2014, 12:23:46 pm
content: Quote from: AcHmed99 on February 18, 2014, 03:48:52 pm1. I did read about the isolated and non-isolated DC-DC converters. While I did understand that isolated have a transformer to keep the i/p and op separate, I did not understand why the non-isolated ones are unsafe. Could you please shed some light (may be in a laymen language).2. Also, I couldn't find IX9908 anywhere locally, butThisseems to be the only Driver IC on RS Website which is cheap and has output voltage more than 26 V. Can I use this as a isolated one ??May be I'm confused here and answer to my 1st question might clear my doubts.

author: desai_amogh
author_rank: Contributor
timestamp: February 20, 2014, 06:53:53 am
content: Ok, I get it now.Quote from: AcHmed99 on February 19, 2014, 11:06:30 pmand yes I am just trying to tinker. Not at all trying to sell anything. Its just that LEDs consume less power and it is the future so want to use/try to use few at home instead of CFLs/bulbs. The ones available in to market here (in India) cost around Rs 800 to Rs 1000 (thats a lot for a light bulb, as 40W bulbs cost Rs 15 and 15 Watt CFLs cost around Rs 150). I am just trying to make a CFL equivalent LED bulb for home use and may be learn something out of it. If at all I am able to pack it in a 'Cool' looking enclosure, why not make couple of them and light the whole house? Moreover I use CFLs and Florescent tubes in the whole house and have to throw them away once blown. I may be able to tinker more if something goes wrong with these LEDs. Thats more opportunities for the spare timeQuoteDigikey is available and a i just checked, few of my friends do order from there and have no issues, its just that I have been ordering from RS for a while now.

author: desai_amogh
author_rank: Contributor
timestamp: March 14, 2014, 11:07:39 am
content: Can you suggest a circuit around this ??

author: Kjelt
author_rank: Super Contributor
timestamp: March 14, 2014, 11:59:09 am
content: http://www.st.com/web/en/catalog/apps/SE412