| Chico Magalhães 02/28/12 22:58 Read: 652 times Florianópolis Brazil |
#186270 - AC Powered LEDs + strobe |
Hello.
I want to make a LED light powered from AC without supply... Yes, I know it is dangerous... Firstly, I thought in using a long series of LEDs to achieve around the 280V peak then a "small" resistor. I found this circuit in the google: I will use just one LED series. I want to know what does the first pair of capacitor (in the input, before the bridge), can someone explain me please? (Looks like I can use ONE non polarized capacitor in the input and ONE polarized capacitor after the bridge). I will use 1w pure white LEDs, 350mA, around 3,8v each. Secondly, I want to turn this in to a strobe, I want to control it with a microcontroller by DMX. I would need some help in how to switch this securely. I dont care if microcontroller blows or even the LEDs, but there could be another DMX devices and it is not nice to burn then all. I thought to use something like an IRF840 (switches much more than 280v) after the retificator, so when LEDs are off the capacitor will be charged, when turned on it will discharge the capacitor to the LEDs... Maybe I'm saying much wrong things here, please dont be to severe. Thank you. PS: This is for my own use, not comercial. |
| Topic | Author | Date |
| AC Powered LEDs + strobe | Chico Magalhães | 02/28/12 22:58 |
| Isolated Switch | Jim Granville | 02/28/12 23:39 |
| Switching | Chico Magalhães | 03/15/12 00:41 |
| Some basics | Oliver Sedlacek | 02/29/12 00:54 |
Not a good design - and expensive  | Per Westermark | 02/29/12 03:00 |
| Answers + need some explantion | Chico Magalhães | 02/29/12 23:55 |
| Cap voltage | Chico Magalhães | 03/01/12 00:03 |
| More than 280V | Oliver Sedlacek | 03/02/12 04:30 |
| Measurement | Chico Magalhães | 03/15/12 00:45 |
| Measurement correct | Erik Malund | 03/15/12 07:54 |
| two caps polarity reversed on DC!! ? | Erik Malund | 02/29/12 07:13 |
| More common long time ago | Per Westermark | 02/29/12 08:33 |
| I was around then | Erik Malund | 02/29/12 09:21 |
| Some polarized capacitors survives AC but not reversed DC | Per Westermark | 02/29/12 10:01 |
| POOOOOOOOOF | Erik Malund | 02/29/12 10:27 |
| Yes, very likely a failure | Per Westermark | 02/29/12 11:10 |
| that need bold face | Erik Malund | 02/29/12 11:44 |
| Back to back connection... | Kai Klaas | 03/02/12 17:05 |
| And another thing... | Andy Neil | 02/29/12 15:30 |
| Pseudo-CC with resistor requires much % V over resistor | Per Westermark | 02/29/12 16:52 |
| chip | Chico Magalhães | 03/01/12 00:11 |
| one of these | Erik Malund | 03/01/12 08:00 |
| Chips | Andy Neil | 03/01/12 14:33 |
| PC PSU | Chico Magalhães | 03/15/12 00:47 |
| Definitely better with lower voltage design | Per Westermark | 03/15/12 01:11 |
| PSU | Chico Magalhães | 03/15/12 18:37 |
Some bricks can inform about rating | Per Westermark | 03/16/12 02:21 |