LEDs

LED lamp with UPS tested

I got several LEXXA 7W LED-VARAVALO bulbs in hoping to replace some aging LED light bulbs with new ones that have a bonus feature: They have an internal battery that allows them to output light even when the mains power is turned off. Those were available cheaply from Finnish shop Motonet (bulbs with pretty similar

Modular LED lamps with IoT

The lighting industry is undergoing a revolution driven by LED technology. LED is is now the dominant lighting technology for all new buildings and retrofits. Yet today, only a small percentage of LED fixtures are supplied with IoT sensors installed. It was estimated 140 million LED fixtures were expected to be distributed in the United

LiShield Can Block Smartphone Cameras for Privacy’s Sake – IEEE Spectrum

Phttps://spectrum.ieee.org/tech-talk/consumer-electronics/audiovideo/lishield-can-block-smartphone-cameras-for-privacys-sake Rules that prohibit photos or videos can prove almost impossible to enforce when nearly everyone carries a smartphone. But a new indoor privacy system has shown how the power of smart LED lighting could prevent people from taking illegal videos of a live events. LiShield has a capability to corrupt digital camera images and videos without

They’re still selling incandescent flashlights? | EDN

https://www.edn.com/electronics-blogs/power-points/4458907/They-re-still-selling-incandescent-flashlights-?utm_content=buffer6638a&utm_medium=social&utm_source=plus.google.com&utm_campaign=buffer   The writer of this article assumed that all flashlights would now be LED units, not incandescent, because of many benefits of LED. But in shop roughly one-third of the lights were LED, one-third were halogen, and one-third were incandescent. Why do they still have non-LED flashlights? This article looks for answer to this and teaches about

Whipping a cheap LED PSU into usable shape | EDN

http://www.edn.com/electronics-blogs/benchtalk/4458731/Whipping-a-cheap-LED-PSU-into-usable-shape This interesting article analyses some cheap mains AC to 12V DC power supplies and how thet can be fixed to work OK. With some modifications they can be used to provide power to LED lighting. The writer of this article has a continuing love-hate relationship with Cheap Chinese Chotchkes – in this case, 18W power

The scientific reason you don’t like LED bulbs

http://theconversation.com/the-scientific-reason-you-dont-like-led-bulbs-and-the-simple-way-to-fix-them-81639 Scientists used to think we could see no more than about 90 flashes of light a second but now we know it’s more like 2,000. During the eye movement, the flicker of light creates a pattern that we can see. It could discourage people from using more energy-saving LED lightbulbs. One obvious way of avoiding

LED current regulator has low dropout | EDN

http://www.edn.com/design/led/4442091/LED-current-regulator-has-low-dropout?utm_content=buffer1967d&utm_medium=social&utm_source=twitter.com&utm_campaign=buffer This article has an intetesting LED current regulator circuit idea built using transistors. The voltage drop on the current sensing resistor r is less than 40mV.  The nominal LED current here is 7.2 mA at 9V. Increasing to 20V causes a current change of +15%, giving a dynamic resistance of about 10kΩ.