Lighting with the lowest requirment

Discussion in 'General Electronics Chat' started by Jensen Leung, Apr 29, 2018.

  1. Jensen Leung

    Thread Starter New Member

    Apr 29, 2018
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    I need to light a light with a lowest amount of current and voltage. What kind of light should I use and can anyone suggest the lowest requirement lighting to me? The requirement of the Red LED is not low enough for me. Someone suggest me to find a similar light on the 'on' light on arduino uno shown as below. What is the name and the specification of the light in the picture and how much voltage or current is required to light up the 'on' light? Thank you
    [​IMG]
     
  2. Dodgydave

    AAC Fanatic!

    Jun 22, 2012
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    LED ( light emitting diode) they come in different colours and sizes, you drive them with a Series resistor or fixed current source.

    You can make it Dimmer by changing the resistor in it's path.
     
  3. dendad

    Well-Known Member

    Feb 20, 2016
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    A lot will depend on what you mean by "light a light". Is this just for an indicator or for illumination? More info really is needed.
    As Dogydave says above, an LED will probably be the way too but what colour and what is your power supply and for what use are all questions that need answering.
     
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  4. -live wire-

    Active Member

    Dec 22, 2017
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    You can also possibly use some kind of florecent thing that gets covered by some mechanical thing. This would only be low current if you don't turn it on/off a lot. Even if it needs 100 mA for the motor, it would only need it for maybe 1/2 a second to mechanically switch the state. Then it would need no current. When I say florescent, I mean like one of those things that glows when exposed to light and can glow for a long time afterwards. Maybe also have light being reflected into it when it is covered so it will still continue to glow.

    But otherwise LEDs are the way to go. You can probably have indicator LEDs that only need 10s of uAs, or bright (directional) LEDs that only need 1-2mAs.

    Just wondering, why do you want it to be so low power?
     
  5. Jensen Leung

    Thread Starter New Member

    Apr 29, 2018
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    It is because the electricity source is a nitinol engine with pulley and motor which can only generate a maximum voltage of 0.7 V. For this situation, what type of application can be used? Is it possible to increase the voltage and current to charge a mobile phone? Otherwise, I just want to light a light bulb with the smallest voltage to complete the project. Thank you very much!
     
  6. tranzz4md

    Member

    Apr 10, 2015
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    You can get a filament type lamp for nearly any voltage, but you can make a different voltage from what you've got as well.

    The Arduino has LEDs.
     
  7. dendad

    Well-Known Member

    Feb 20, 2016
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    Can you post pictures? A nitro engine driving a motor to generate 0.7V sounds odd to me. Are you sure it is only 0.7V? How are you measuring it. I cannot quite figure out why you only get 0.7V out unless you are turning the motor quite slowly. What is the motor?
     
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  8. DECELL

    Member

    Apr 23, 2018
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    I have just searched the web for nitinol engine, but i think it would be more polite not to presume we know that you are thinking. State an end goal and load a picture of your idea. So 0.7V and how many mA of output current have you got to play with? You can do a fair bit with 0.7V. Eg, A BQ25504 from TI will start up on 0.3V or less. Check out "energy harvesting ICs"
     
  9. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
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    You can get more voltage (at the cost of current) or you can more current (at the cost of voltage) but you can't do both at the same time.. Voltage x Current = Wattage (or Wattage/Voltage = Current.. or Wattage/Current = Voltage)
    Have you done any testing to see what your source is capable of in terms of wattage? (or how much current can it provide at this .7V?)

    With 10W you can use 1V @10Amps or 10V @1 Amp,etc.... (ignoring conversion losses for discussion sake)
     
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  10. KJ6EAD

    Senior Member

    Apr 30, 2011
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    This sounds like an engineering school contest using a muscle wire spring to drive the motor as a generator and see who can produce a light output the longest.
     
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  11. Jensen Leung

    Thread Starter New Member

    Apr 29, 2018
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    yay i am doing a nitinol engine! What is BQ25504 from TI? Thank you!
     
  12. Jensen Leung

    Thread Starter New Member

    Apr 29, 2018
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    The voltage and current is about 0.6V and 0.2A
     
  13. Jensen Leung

    Thread Starter New Member

    Apr 29, 2018
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    I want to light a LED bulb first. If this goal is achieved, i want to use the nitinol engine to charge a phone
     
  14. -live wire-

    Active Member

    Dec 22, 2017
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    How did you measure the current?
     
  15. dendad

    Well-Known Member

    Feb 20, 2016
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    Please post some pictures.
     
  16. Jensen Leung

    Thread Starter New Member

    Apr 29, 2018
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    0.53V.jpg
    this is the picture and i measure current with the voltmeter?
     
  17. -live wire-

    Active Member

    Dec 22, 2017
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    And you measured current by shorting it with through the meter?
     
  18. Jensen Leung

    Thread Starter New Member

    Apr 29, 2018
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    same method with measuring the voltage
     
  19. -live wire-

    Active Member

    Dec 22, 2017
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    So yes if you switched it to the current mode and put the probes in the current sockets.
     
  20. dendad

    Well-Known Member

    Feb 20, 2016
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    Thanks for the picture :)
    Will it turn the motor faster if you swap the pulleys? Having such a big pulley on the motor will make it run slower I think.
     
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