Search for UVB (305-315nm) SMD led's  - Page 1
Forum section: electronics / projects

author: Ashwin619
author_rank: Regular Contributor
timestamp: November 20, 2022, 10:09:55 am
content: Hi there,I am searching for some UVB (305-315nm) SMD led's that can be used as an replacement to this ->There are a couple of reasons why I am NOT opting for this product from Philips. One being the cost and secondly the high operating voltage of this lamp which I am not sure about the reason behind it (no of Led's in series OR high voltage plasma based lamp ?). I am also planning to make a small CC based converter for this to drive it within its limits.A search on Mouser & LCSC didn't yield any good results and Digikey happens to have thishttps://www.digikey.in/en/products/detail/seti-seoul-viosys/CUD1GF1A/9997681which is kind of expensive for a single LED.I would really appreciate if someone could suggest any good sources from where I can get these LED's.

author: jpanhalt
author_rank: Super Contributor
timestamp: November 20, 2022, 12:05:54 pm
content: These companies claim to offer UVB LED's:https://www.intl-lighttech.com/applications/uvc-ledshttps://www.uvledchip.com/uv-led.htmlHave you tried Googling for them?

author: LaserSteve
author_rank: Super Contributor
timestamp: November 21, 2022, 04:46:32 am
content: The Philips lamps shown are fluorescent tubes.The voltage across them can be quite low once lit.Steve

author: Ashwin619
author_rank: Regular Contributor
timestamp: November 21, 2022, 08:56:38 am
content: Hi jpanhalt,I did search for them on google while restricting my scope within major component vendors as I didn't want to go through the hassle of contacting them and getting quotes, customs and whatnot. Also, I did come across the second website of IBT where they had the required product although I didn't proceed with it as the prices were not mentioned.The first link also got the required product, but at 21.5$ for 5 pieces + shipping, I think it may be a little over my budget. Nevertheless, I'll send some enquiries for quotation.Thanks for your suggestion.

author: Ashwin619
author_rank: Regular Contributor
timestamp: November 21, 2022, 09:18:10 am
content: Hi Steve,I also thought so, although I was not completely sure as its not mentioned what kind of light source are they utilizing. Or maybe I missed the detail somewhere. generating the initial high voltage for these fluorescent lamps may prove to be a challenge especially since the HV value is not mentioned in the spec sheet. Do you think they might be utilizing a Mains (240Vac) + Ballast + Bimetallic starter switch combination for this?The Ballast may also have to be sized accordingly (V=L di/dt) so in order to not exceed the breakdown of the Luminous gas OR perhaps not to destroy the filament.Let me know if you have any idea regarding some low cost + LED (smd) alternative for this product.Regards,Ashwin619

author: Zero999
author_rank: Super Contributor
timestamp: November 21, 2022, 11:49:00 am
content: UVB/UVC LEDs are good, but the at shorter wavelengths fluorescent lamps start to become the better option efficiency wise. LEDs are less efficient at shorter wavelengths and fluorescent tubes increase in efficiency, since the loss due to the Stokes shift becomes smaller. There are other advantages to using LEDs: size, lower voltage, no mercury or glass, more concentrated light, longer life.The tubes shown in the attachment to the original post, have an efficiency from 13% to 21% and output from 1.2W to 20W, whilst the LED is only 1.1% efficient and is a very low power at only 1.2mW.The tubes will work with standard fluorescent lamp ballasts. I recommend electronic ballasts where applicable, because the tube will last longer and they're more efficient.

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: November 21, 2022, 11:57:10 am
content: https://www.aliexpress.com/item/1005004901643798.html?spm=a2g0o.productlist.0.0.22f4618e78EXhJWhy not give these a try?

author: SeanB
author_rank: Super Contributor
timestamp: November 21, 2022, 01:06:29 pm
content: Look at aquaculture suppliers, as they use those UV lights to disinfect the pond water, and thus they make LED versions of the UV tubes that are purported to be a drop in retrofit for the UV output tubes, both linear flourescent, PL and CFL lamps.