house bulb LED cluster  - Page 1
Forum section: electronics / beginners

author: ChanceLogan
author_rank: Newbie
timestamp: January 21, 2018, 06:10:53 pm
content: I have a bunch of LED clusters with ( 3 dyes per cob 8 cob per board 36 fwd volt ) . I want to run them on 12 to 14 volt ( auto) . Question is do i strip them off the boards they are on and make new boards so i can run them on the 12 v. Maybe it is better to make some type of dc to dc boost converter . The boards are a good size and shape just need 36v to run them. Thanks for any input . I am good with all the auto side of this and under stand boost converters on paper .

author: Zero999
author_rank: Super Contributor
timestamp: January 21, 2018, 09:58:21 pm
content: I'd opt for a boost converter. It might be very difficult/impossible to get the LEDs off the boards without damaging them. LEDs should be driven by a constant current source, so he boost converter will need to regulate the current, not the voltage.

author: ChanceLogan
author_rank: Newbie
timestamp: January 22, 2018, 05:16:13 pm
content: thanks for your thoughts . Getting them off is easy ish and putting them on is easy but making or buying a board that will handle the heat is where i am lost . boost converter to me seams like the easy and more flexible way to go .

author: kalel
author_rank: Frequent Contributor
timestamp: January 22, 2018, 06:16:18 pm
content: Is there a chance you could cut the traces connecting the chips in series on the board and then solder some wires to the COBs directly (if they have exposed +- contacts anywhere that you could solder to) so that you get your desired voltage?Note that you would still need a driver (constant current module would work best).The only advantage of lower voltage is the potential for more efficiency. Boost converters are not as efficient as having the approximate voltage needed.It would surely be simpler and cleaner to use a step up/boost converter as recommended. You can probably get one very cheap as long as it is not too many amps. China has a lot of them, but you may need to wait a bit for it to arrive if you go that route.

author: Zero999
author_rank: Super Contributor
timestamp: January 22, 2018, 07:00:26 pm
content: One way to get better efficiency from a step-up converter, is to use a tapped inductor.https://www.powersystemsdesign.com/articles/tapped-boost-converter-modeling/18/5482Here's an application note about driving LEDs, with a tapped inductor boost converter.https://www.microsemi.com/document-portal/doc_view/124899-ips401-application-note

author: ChanceLogan
author_rank: Newbie
timestamp: January 22, 2018, 09:14:12 pm
content: Neat ... Size... Efficiency .... They are not much of a concern has to be reliable that is what maters . they will be running as extra lights on a truck in off road (in fields and construction sites ) . I know there are items on the market i can buy but wheres the fun and learning in that . If it all fails i will still of learned some thing . so any more ideas would be great but so far yous are a great help in pointing me in a good direction . Thanks for not flaming a new guy on here if there is any info i can give yous to help yous help me just let me know.