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    Using this simple Christmas LED lights decoration circuit, you can make an 18 LED flasher to decorate the Christmas Tree. The White, Blue and Red LEDs flash at different rates to give a colorful display. It is a light sensitive circuit so that it will turn on in the evening automatically and stays on till morning.

    The circuit uses the popular Binary counter IC CD 4060 to flash the LEDs at different rates. Components C1, VR2 and R1 form the oscillator and the output pins 7, 5 and 4 become high / low sequentially. When one output turns high, a set of 3 LEDs turn on and when the same output turns off, the second set turns on. This sequence is similar in the other two sets of LEDs also but with different timings. The speed of the Flashing can be controlled through VR2.

    Christmas LED Lights Decoration Circuit Schematic

    Christmas LED decoration circuit

    Christmas LED decoration circuit schematic

    LDR is provided with VR1 to activate the IC in the evening. In day light, LDR conducts and keep the reset pin 12 of IC1 high to inhibit it from working. When the day light ceases, pin12 becomes low and the flasher starts working. VR1 adjusts the sensitivity of LDR at the required light level. If more LEDs are required, increase the supply voltage to 18 volt DC. The circuit can be powered using a standard 12-18 volt 500 mA adapter.Use High bright transparent LEDs for attractive display.

    LDR informations

    attentionThe author D Mohankumar is not an active member anymore. Please take into consideration that the presented information might not be correct.
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    28 Responses to "Christmas LED Lights Circuit"

    1. sir have you try this circuit?
      Is it working?

    2. yes, the circuit works.

    3. What are the power losses in the resistors R2-R7 ? Can they be eliminated by using more LEDs instead ? Also, this circuit could be powered from your transformer-less AC power supply circuit, or AC led driver circuit, if one could match the voltage output of the AC voltage dropping capacitor with what is required here. My problem is that I don’t know how to calculate the voltage output of that capacitor, only know how to calculate current output at various points/values on the rectified AC voltage wave.

    4. this is not wotking puta ka. revise the circuit. ASAP

    5. what is 1m on pin 11

    6. May I have a PC Board Layout?
      thanks before

    7. Hi nid pcb layout of dis circuits tanx

    8. Hi Nicusor, Yes you can replace the resistors with additional LED’s.
      Connect one LED in series with a variable resistor of 3k3 or maybe even bigger across 12vdc.
      Start with max resistance, and adjust until the LED burns nicely. Then measure the voltage drop across the LED.
      Divide that into 12, adjust your answer to the next larger whole number, and you Have the number of LED’s you need per string.
      As you can see, there are six strings in the circuit, so you will need to buy six times the number you determined.
      Alternatively you can read the voltage drop across the LED from the data sheet, and calculate it from there, but that takes all the fun out of the hobby.

    9. Reading thru Nicusor’s comment again, the following: I personally would not power this circuit from mains directly, due to safety considerations

    10. please has some done the circuit? and it is working? i want to know befor buying the componet.

    11. please can i replace the C1 0.22 with 1uF 16v polyrise capacitor?

    12. the capacitor 0.22uF is a ceramic or electrolytic?and can i have breadboard layout of this circuit?

    13. sir it is nt wrkng..?
      all LED’s r continuously glowing.
      12-0-12 gives DC o/p 15v..
      is it require 1 LED’s in all the LEDs groups?
      guide me pls..?

      • Jim Keith says: on December 16, 2012 at 7:38 pm

        I assume that you have a 12-0-12VAC transformer that is rectified and filtered. If so, the DC output voltage at light loads may be close to 20V and exceed the voltage rating of the IC (18V).

        What is the no-load voltage?

      • Anand shingwekar says: on December 17, 2012 at 10:47 am

        No load voltage is 18V.

        i have decided to put 7812 regulator?

      • Anand shingwekar says: on December 18, 2012 at 3:30 am

        when 7812 is connected it gives 12V regulated supply…
        when supply is switched on all the LEDs r continuously glowing nd oscillator circuit is nt wrkng…?

      • Jim Keith says: on December 18, 2012 at 4:10 am

        IC may be toast –replace

    14. der is no oscillation with VR-2??

    15. what type of capacitor is used in the circuit? if is it non polarised 0.22 micro farad capacitor then what type of capacitor can i use instead of it?

    16. Yes. The circuits works. Raising the value of 0.22uf, the oscillations will be slow, lowering it, oscillations will be fast. Blue LEDs flash fast, white medium, red slow. The LDR is optional and may not be used and VR1 then can be replaced with 100K fixed resistor.

    17. sir i want a all ldr circuits plz help me>>>>

    18. I am going to try this circuit. I may try using a power n-channel FET coupled to the 4060’s outputs to drive as much as 12 watts of leds. I am impressed with the potential of driving 6 independent groups of LEDS? I am going to try using IRF510 power FETs with their gates fed through a 10,000 ohm series resistor and a 100K ohm resistor from the gate to ground (-Vcc, earth, group) to discharge the gate’s capacitance. I will post again after I try it.

      I do have a general question. I am new, well not exactly, to this hobby after a 42 year hiatus. Is there is easily usable and without fee electronic schematic drawing program or tablet Andrid App anyone can suggest?

    19. This post from Electronics Stack Exchange explains why the circuit won’t work in the form it’s in here, but also shows how to fix it… http://electronics.stackexchange.com/questions/164449/confusion-over-a-simple-4060-led-blinker

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