Newbie - Power Arduino in truck

Discussion in 'Automotive Electronics' started by Lutronjim, Apr 26, 2019.

  1. Lutronjim

    Thread Starter New Member

    Apr 26, 2019
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    Want to use Arduino in my truck for various projects. Keep reading horror articles about the '12v' power available.
    Since 14v+ is normal when charging and Arduino maxes at 12v, could I use a resistor to lower voltage to 6v and a Max809 chip to filter noise. This would seem to be a low cost way for protection,

    I am a novice on reading circuits much less design.

    Thanks for any advice.
     
  2. danadak

    Distinguished Member

    Mar 10, 2018
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  3. djsfantasi

    AAC Fanatic!

    Apr 11, 2010
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    A resistor is NOT a good idea. It won’t have a reliable output as the Arduino current draw changes. You need a circuit to regulate the voltage.

    Look into a DC to DC converter with a well-filtered 5VDC output. Then power the Arduino through the Vin pin. This bypasses the onboard regulator. That’s where the 12VDC limit is.
     
  4. narkeleptk

    Member

    Mar 11, 2019
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    LM7805 works well if you want to build something or make the atmega chip stand alone but for just basic powering of an arduino you could pretty much use any usb adapter like what your phone uses.
     
    Last edited: Apr 27, 2019
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  5. Lutronjim

    Thread Starter New Member

    Apr 26, 2019
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    Thanks for comebacks. I didn't think about load changes with resister.
    I am out of state right now - I will try to digest the 2 'regulators' when I get home.
    I am trying to build a device to control lights. I have the code running on uno with led's for testing.
    I am thinking about using a solid state relay to handle current.
    I will try to containerize later.


    Again thanks
     
  6. ScottWang

    Moderator

    Aug 23, 2012
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    If you trying to use 14V or 14.2V to plugin to the arduino power jack(7~12V), probably you can in series with 4 1N4001 and plugin to the power jack.
     
  7. Lutronjim

    Thread Starter New Member

    Apr 26, 2019
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    I looked at the TI LM7805CT/NOPB device for suppling power. It puts out 5v and will work in a hot environment like a car - also less than$2. I looked at the TI TPS1H100-Q1 for switching the 12v+ to the bulbs but got quickly lost at the numerous connection points
     
  8. ian field

    AAC Fanatic!

    Oct 27, 2012
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    Most types of PSU applicable to this have a series pass semiconductor that would dump the input voltage to the load if it fails.

    A flyback type driving a stepdown transformer is more or less fail-safe.

    I'd probably go the lazy route - a dirty great shunt regulator and current limiting resistor. They're very inefficient but they effectively shut down if the semiconductor fails.

    A big enough Zener diode might not be easy to find, but you can boost it with a transistor. The TL431 application note gives a pretty good idea how to do this, and the 431 programmable Zener makes it easy to trim out the Vbe loss on the boost transistor.
     
  9. geekoftheweek

    Active Member

    Oct 6, 2013
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    About the easiest way (but not the cheapest) is hack a USB charger you plug in to your car. Usually they will put out one or two amps, but a little looking could find a higher power unit. I used one on a project for a few years before a loose ground wire killed it. They have some circuitry to handle load dumps and such already built in. The downside... they cost a little more, they will take some custom mounting, and wiring them up can be tricky depending on how they were built.

    If you want to use your analog to digital converters you may need some more filtering depending on how cheap the charger was built so it may be better to go with a custom made power supply in that case.
     
  10. Lutronjim

    Thread Starter New Member

    Apr 26, 2019
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    ian field you are way over my head.

    I will try to produce a drawing of what I think I now know sometime this week.
     
  11. mvas

    Active Member

    Jun 19, 2017
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    Last edited: May 4, 2019
  12. ian field

    AAC Fanatic!

    Oct 27, 2012
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    Use automotive spike suppressors on the input and an SCR crowbar protection on the output. A fuse might come in handy too...……..
     
  13. Lutronjim

    Thread Starter New Member

    Apr 26, 2019
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    When researching to do drawing I was seeing a npn transistor driving a pnp transistor or other device for high side switching. Thus adding another component.
    Then I found another TI device - the TSP1H000-Q1. IT seems to be built to be controlled directly by a microprocessor.
    See http://www.ti.com/document-viewer/TPS1H000-Q1/datasheet/features-x5241#x5241 .
    This device as well as the LM7805 are built for the auto environment.
     
  14. Lutronjim

    Thread Starter New Member

    Apr 26, 2019
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    Can find any info if the TSP1H000-Q1 can be directly connected to Arduino. Joined TI user forum and posed that question.
     
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