making Ebay bought 8 function LEDs stay on all the time. - Page 1
Forum section: electronics / beginners

author: crackers
author_rank: Newbie
timestamp: April 04, 2020, 04:32:53 pm
content: Good day. First time poster and extreme newbie to this forum and electronics but I know enough not to get electrocuted. Apologize if I am asking something that has been asked or discussed before, if so please direct me to the right thread. I am working on a project using some cheap LEDs I bought on line. The LEDs are the perfect size but they have a button and can do eight different functions (Blink, chase, flash etc.) the last push results in "constant on". Whenever you unplug the lights and plug them back in, it goes back to flashing. I just want to plug them in and have then always come on—no pushing buttons no flashing lights just light when plugged in. Is there any way I can cut a circuit or solder or un solder a wire so when I plug the LEDs in they are always on - no blinking or flashing? I opened the control box and took three pictures of the circuit board. I checked Big Clive and a site from Australia that covered this topic all the advice on the circuit boards are 7 years old and mine looks nothing like what was discussed. This is a standard plug using 110AC even though the board says 220, it is 110AC that is going in. There is a bridge rectifier that converts the 110AC to about 105 DC. I have learned this by using a volt meter and checking on line. There are 100 LEDs in the string, 3 wires to the LEDs. The first ten LEDs have a resistor soldered to them, all the others do not. Any advice and help is appreciated. Thanks and stay healthy.

author: TheHolyHorse
author_rank: Regular Contributor
timestamp: April 04, 2020, 04:47:25 pm
content: The flashing is probably the startup mode of the controller. If you can find a part number you could reprogram the controller.But the simplest thing to do would be to remove the controller and just hardwire it.

author: Twoflower
author_rank: Frequent Contributor
timestamp: April 04, 2020, 05:54:48 pm
content: Be very careful with that thing!First: There is no galvanic insulation at all. So even the LEDs are connected to the mains! All measurements must be taken with caution. Even pressing the button without the housing might have unwanted side effects.And second: The wiring is terrible. On the first picture there is a strand of the second wire (count from the top) nearly making a short to the first one. And these are the 220/110V wires!

author: amyk
author_rank: Super Contributor
timestamp: April 04, 2020, 09:10:27 pm
content: That's a dedicated IC powered by what appears to be a 150K/2M divider. LEDs are controlled via transistors and may be PWM'd even in constant-on mode, so hardwiring the LEDs may burn them out --- you'll need to check the voltage of the series string and determine their normal operating current.Older versions of this circuit have an EEPROM position for remembering the last setting, but that's been cost-optimised out of this one.

author: TheHolyHorse
author_rank: Regular Contributor
timestamp: April 04, 2020, 09:27:12 pm
content: Quote from: amyk on April 04, 2020, 09:10:27 pmWith hardwire I include properly driving them, just without the controller. Maybe I should've explained myself betterQuote from: Twoflower on April 04, 2020, 05:54:48 pmConsidering all of this, maybe you should just get another led driver that doesn't require modification and wont accidentally shock you with mains.