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led night lamp schematic

LED Night Lamp Circuit

The design of the LED night lamp circuit (bedroom light) is similar to that of many commercially available products. However, the light circuit does not use any kind of bulky and noisy stepdown transformers, but a capacitive potential divider is inserted in a simple manner to provide a constant current for driving the light source. Here a high-efficiency, low current blue LED is used as the light source. The design is safe, simple and stable!

Night Lamp Circuit Schematic

led night lamp schematic

When input power (AC 220V) is available, capacitor C2 is charged through C1 and R2 and bridge rectifier assembly D1-D4. Zener diode D5 limits the voltage across C2 to a safe value of near 15V. This low voltage dc supply is then fed to the LED (D6) via current limiting resistor R3. When the input supply is removed, LED stays on unchanged for a short time and then diminishes gradually. No instant darkness when the supply is switched off!

Related Products: Lighting Solutions

After construction, enclose the circuit in a small plastic box. Drill a 5mm hole in the centre of the enclosure and fit the LED in a suitable LED holder in the 5mm hole. Finally fit a supply input socket and, optionally an on/off switch at the rear/side of the enclosure.

WARNING! Great care should be taken when working with this led night lamp circuit since it is connected directly to the fatal mains supply.

27 Comments

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  • neetu saini

    is it safe if i will use transformer for 230v power supply..instead of capacitive voltage divider..??????

  • Petro

    Am a new electronic can u help and tell me how does this project work??

  • faizan

    sir i am new in electronics……wheres the output in this circuit……….

    • Daniel

      Don’t other.

      If you can’t tell where the input and output are when dealing with AC main, you simply don’t belong there.

      Do some study first, before you get electrocuted !!!!

  • mahesh

    i need circuit for led bulb and it should work both day light and bedroom light we can use both

  • krishna

    Shall i replace Blue LED with white LED???
    or is there any spec?

    • faizan

      plzzz…help me iam new in electronics plzz..tell me wheres the out put…..and can i connect the 25 watt bulb

    • Rajeev

      White LED also works. In fact I have been using ultra bright LED in this circuit for past many months.

  • Mart

    Check out this webpage and the efficient LED driver circuit and it also explains why it is energy efficient, http://www.marcspages.co.uk/tech/6103.htm

  • Rajeev

    Hello! I made many such lamps with D5 4.7V Zener diode, C2 10Mfd 50 volts and did not use R3. They have all been working well at various locations ( some continuously ) for more than 18 months! The LED can be blue or white. R1,1M bleeder resistance is very important for safety.

  • Darren

    Hi there

    Awesome circuit ..and a great article .
    I was wondering how any what to change so I can supply 5 V with about 500ma or close to it.
    I also would like to know if this will be noiseless enough to power an ATTiny85 with a wireless receiver attached to it. The circuit will also have a bt-139 triac attached.
    I would really appreciate your suggestions on what I could add or change to make it work.
    Kind regards
    Darren

  • Mahesh

    Why does the LED night lamp keeps on lighting dimmly even after switching it off for long long time, means full night 6 hrs, & cant determine the same in day, as daylight is brighter?
    Is it continuously lighting dimmly? or discharging & switching off, cant determine!
    What is the power stored in watts & lost , once we start the night lamp?
    I know its the capacitor charged which is draining & lighting he LED. But still the question is same.

  • dani

    Hi
    How many watts and amper were used LED?

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