Connect with us

am i grounding this lm317t constant current circuit correctly?

Discussion in 'General Electronics Discussion' started by khankll, Jun 13, 2012.

Scroll to continue with content
  1. khankll

    khankll

    110
    0
    Feb 6, 2011
    hi
    title says it all.
    here is the circuit how i interpreted it.. is it correctly grounded..? oriiginal ckt is in lm317 datasheet ..

    my input is 12 volts and output is a constant current close tp 100mA and there are 4 nicd cells in series.. (pack)
    thanks
     

    Attached Files:

  2. Harald Kapp

    Harald Kapp Moderator Moderator

    11,014
    2,506
    Nov 17, 2011
    What a question. Of course, the circuit is from teh datasheet (https://www.national.com/ds/LM/LM117.pdf page 18) and will deliver I= 1.2V/R.

    However, I wouldn't recommend this circuit for charging batteries. There is no limiting element (time, dV/dt or similar) to terminate the charge when the batteries are fully charged. This can lead to destruction of the batteries.
    Use one of the specialized charger ICs instead.

    Harald
     
  3. khankll

    khankll

    110
    0
    Feb 6, 2011
    thanks but no thanks.:D. i didnt asked these things..:mad:
    my question is still same..
     
  4. Harald Kapp

    Harald Kapp Moderator Moderator

    11,014
    2,506
    Nov 17, 2011
    I'm sorry, but I don't get it. Could you please rephrase your question?
     
  5. CocaCola

    CocaCola

    3,635
    5
    Apr 7, 2012
    No thanks? Harald answered your question with "Of course" and yes you did ask that question...

    Your circuit is just a hand drawn faithful copy of the one in the datasheet, minus the decoupling cap... Thus the "Of course" reply as to it being correct, it's right out of the datasheet correct, it's not interpreted at all...
     
  6. khankll

    khankll

    110
    0
    Feb 6, 2011
    sorry a bit language issue has arisen.. i think.. sorry harald bro..
    actually here is excessive blackouts.. 1 hour blackout after every 3 hours is normal..so it was just to go blackout that i couldnt properly omprehend his reply.. and to explain more i typed a whole paragraph but light went .. so i just posted the short reply from my mobile..

    my issue is already solved.. here is solution
    http://sv1bsx.50webs.com/charger/charger.html

    ...reason i wanted to do charging this way is that i have intellignt charger but issue is ...
    the charger expects cells of aa or aaa sizes.. and each cell is individually cgarged..
    plus the battery pack that i have is tab soldered and is in pack.. it wast used for few momnths and the voltage of entire pack were .1 volts instead of 4.8volts.. so wnted to trickle it with small current to bring the pack voltage to sufficient level.. then hope the device in which the pack will be installed accepts it and charge it from their nwards ..


    its on charging .. and charging at 80mA of current let me se if it brings the cells to life..

    once agaimn a heartly sorry for being blatent ..but language issue arose.. i thought the of course was part of ur immediuate next statement..
     
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

-