Connect with us

How to get 3.3 V from a charged LiPo battery?

Discussion in 'Power Electronics' started by seanspotatobusiness, Mar 16, 2017.

  1. seanspotatobusiness

    seanspotatobusiness

    193
    4
    Sep 11, 2012
    I would like to power an Arduino Mini/Nano at 3.3 V using a LiPo phone battery with max 4.2 V. How do I render the voltage from the battery suitable for the Arduino? 4.2 V seems to be less than the minimum for all the regulators I've looked at. What should I look for? Thanks!
     
  2. Bluejets

    Bluejets

    3,489
    706
    Oct 5, 2014
    Another battery.
     
  3. seanspotatobusiness

    seanspotatobusiness

    193
    4
    Sep 11, 2012
  4. BobK

    BobK

    7,631
    1,657
    Jan 5, 2010
    You can find low dropout regulators that will drop a couple of hundred millivolts. Or you can use a buck converter.
    Bob
     
    seanspotatobusiness likes this.
  5. seanspotatobusiness

    seanspotatobusiness

    193
    4
    Sep 11, 2012
    I've discovered that the board has its own regulator and will happily accept 3.3 V to 12 V so no external parts are needed!
     
  6. Bluejets

    Bluejets

    3,489
    706
    Oct 5, 2014
    The unit you link to in #3 above is a linear regulator.

    You have to be careful in the translation between Chinese and English, many times they get it wrong.

    Edit....according to the description, this should be the unit you require.
    This is voltage adjustable up and down.

    http://www.ebay.com.au/itm/New-Boos...478171?hash=item58c105649b:g:spAAAOSwEeFU8WTp

    There are others that just go up and there are others as shown below in youtube, that have current regulation as well.



    As a further note, this bloke has a lot of very good videos on electronics, well presented and easily understood.
     
    Last edited: Mar 19, 2017
  7. Audioguru

    Audioguru

    2,586
    586
    Sep 24, 2016
    A single Li-PO cell is 4.2V when fully charged and its charging current has dropped low, 3.7V about halfway during a discharge and 3.2V when it must be disconnected. If you do not disconnect it when its voltage is 3.2V then the voltage will go lower and ruin the battery. A Li-Po cell that has discharged too low is dangerous because it might explode or catch on fire if it is attempted to be charged. A good Li-PO charger will detect that a cell voltage is too low and refuse to charge it.
     
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

-