Connect with us

Types of LED bulbs inside circuitry ?

Discussion in 'LEDs and Optoelectronics' started by Externet, Mar 7, 2019.

  1. Externet


    Aug 24, 2009
    Some plain 120VAC LED bulbs do light up faintly as intended when connected this way, some do not. What could be different inside the bulbs, is there different circuitry 'architectures' in the industry ?


    Capacitor = 0.01μF/250VAC
  2. Harald Kapp

    Harald Kapp Moderator Moderator

    Nov 17, 2011
    Definitely yes.
    Simple LED lamps may have only a rectifier, a capacitor and a few current limiting resistors.
    Better lamps have an integrated circuit to control the LED current more precisely and to account for varying input voltages. These latter are possibly more susceptible to the phase shift between current and voltage introduc ed by your series capacitor.

    Imho start by abolishing imperial units first. The dB at least is useful :D
    davenn likes this.
  3. 73's de Edd

    73's de Edd

    Aug 21, 2015
    Sir Externet . . . . . . .( Hopefuly, soon to get yourself an Internalnet.)

    I have noted that most of the LED lamps are rated at 5W--9W--18W--23W and some, even a bit more than that, if they are equating with the equivalent light output of greater than a 100 incandescant lamp.

    With your choice of that .01 ufd capacitor you are only letting the power of passage of an ~265K resistor, by virtue of its capacitive reactance at 60~.
    Try shifting your capacitor value, decades up and you should start getting some more realistic light levels with a 1 or 10 mike capacitor, but with a .1 still being a flash in the pan.

    Some circuitry just rectifies to DC and uses resistive dropping to feed series LEDS . . . or clusters.
    Some circuitry rectifies and uses switch mode conversion to feed the leds.
    I would expect your experienced pale response to be from the first design of circuitry and the second type, not even getting enough power input OOOOMMMPPPPHHH to even start up the circuitry.

    73's de Edd . . . . .

    The first testicular guard, the "Cup," was used in Hockey in 1874 and the first helmet was used in 1974.
    That means it only took 100 years for hockey players to realize that their brain is also important.
  4. hevans1944

    hevans1944 Hop - AC8NS

    Jun 21, 2012
    NOT. Helmets were a marketing ploy having almost nothing to do with personal safety. Compare the modern users of bicycle helmets, motorcycle helmets, football helmets, combat war-helmets, baseball batting helmets, deep-sea diver helmets, jet fighter pilot helmets, astronaut helmets, and coconut shell helmets. Different strokes for different folks, but it still all boils down to marketing as to what you get (or may want) in a helmet. The realization of the importance of the brain is irrelevant, and even a hindrance, to successful marketing. During American involvement in wars, many GIs used their helmets as cooking utensils, ad hoc flight seats during helicopter rides into combat, as well as for use as water containers.:D
    Last edited: Mar 7, 2019
  5. 73's de Edd

    73's de Edd

    Aug 21, 2015
    Last edited: Mar 7, 2019
  6. hevans1944

    hevans1944 Hop - AC8NS

    Jun 21, 2012
    Yes, you are right. And most of us (me included) do appreciate your sense of humor here on EP.
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day