led dimming

  1. Danirov

    Fail: Low battery indicator blink and dim

    Hi! I would be very grateful if you can help me. I have been building some circuits to turn on a LED when the battery is low (images), but there is a problem: The led dim and blink between the OFF and fully ON state for some minutes. My circuit consumes 0.23A and is supplied by a 3.7v/1400mAh...
  2. TimBav

    How to dim 4.5v fairy light LEDs on a USB supply?

    Hi folks, plea for help. I've wired my daughter's LED fairy lights to a USB-2 supply, but now they're much brighter than the 3 AA batteries made them (and we quite preferred when the batteries were half flat), so I've been trying to find a variable resistor to put in series to reduce the...
  3. B

    My first electronics project, array of 9 Cree XP-E2 with dimming

    Hi all, I'm working on a micro controller project to do race timing for rowing regattas. It's coming along pretty nicely and I want to add one component: A finish light that will be turned on and off by the microcontroller. The light needs to be seen from a distance in sunny conditions. I want...
  4. Dan Aronin

    XL6005 understanding the datasheet

    Hi all, a driver circuit needed for lighting a 30W LED* (one color) - I had a look at the XL6005 datasheet and wanted to make sure I understand it properly based on the following diagram**: 1. To drive the LED with 300mA I should make RS = 0.73 ohm (ILed=0.22/0.73=0.3A) 2. To limit the max...
  5. Zack Maness

    Need help designing a power saving circuit for two strings of mixed LEDs. (I don't have a lot of experience designing circuits)

    I made a few Lichtenberg figures and I want to mount them in shadow boxes. I built some LEDs into the box (Three UV along the top and one red on the left under the blue tape) and I am planning on pouring about an inch of epoxy to cover the LEDs and disperse their light. For a power supply, I am...