Help salvaging the screen and battery from a broken calculator

Discussion in 'General Electronics Chat' started by -live wire-, Apr 16, 2018.

Do you think I can salvage the battery AND the screen?

  1. Yes.

    0 vote(s)
    0.0%
  2. Just the battery.

    0 vote(s)
    0.0%
  3. Just the screen.

    0 vote(s)
    0.0%
  4. No.

    0 vote(s)
    0.0%
  1. -live wire-

    Thread Starter Active Member

    Dec 22, 2017
    800
    70
    My Ti-nspire CX calculator recently broke. The buttons stopped working, and when I opened it up it became clear there was nothing I could do. It was out of warranty. But there are still some things I would like to salvage. There is a nice battery and a decent color screen.

    The battery is 3.7V 1.2 Ah.
    https://www.amazon.com/Rechargeable-Battery-Nspire-CAS-MODEL/dp/B00SMRLU3O
    So where could I get a charge/protect/boost circuit for it? And I cannot find the max continuous current draw.

    The screen has some weird connector but it can easily be taken out. It seems a shame to just dispose of it. So, where could I find a chip that allows an Arduino or something to interface with that screen and has the proper connector for it? Any suggestions would be greatly appreciated.
     
  2. be80be

    AAC Fanatic!

    Jul 5, 2008
    1,689
    331
    I've got 100's of old screens the long number on the back is you only hope for a data sheet

    I Could of kicked my butt I could of done way better had I left them in the stuff and tracked down the power and data lines.
     
  3. -live wire-

    Thread Starter Active Member

    Dec 22, 2017
    800
    70
    There is kind of a part number on the back but it is mostly covered up by the styrofoam. I have done some googling and cannot find the part number. Anyone know the type of connector and how I can get it to interface with an arduino?
     
  4. dendad

    Well-Known Member

    Feb 20, 2016
    1,897
    481
    I think you will be better served to try to clean the buttons and get the calculator working again.
    Generally. there is almost no hope of driving displays like these from an Arduino.
    But the battery could well be used with an appropriate charge controller. I fit is a LiPo cell, here is a LiPo cell charger/protector from Ebay.
    Charger.png
    If you get one, make sure it is the 6 connector type. There are come that are just a charge controller an not an over discharge protector too.
     
  5. -live wire-

    Thread Starter Active Member

    Dec 22, 2017
    800
    70
    The battery seems to have 3 terminals, not two. Two of them are common. What are they, and do I need a different type of C/P/B circuit? And is there really so little hope for interfacing with the screen? And kind of separate, are there arduino to HDMI boards at least?
     
  6. dendad

    Well-Known Member

    Feb 20, 2016
    1,897
    481
    Often there is a temperature sensor in the battery. That may be the other connection.
     
  7. -live wire-

    Thread Starter Active Member

    Dec 22, 2017
    800
    70
    So ignore the safety feature because you don't want things to be too safe...? :) But as long as I am not stupid do I really need it?
     
  8. BobTPH

    Senior Member

    Jun 5, 2013
    1,182
    234
    If two are common, there there are really only 2 connections.

    Bob
     
  9. -live wire-

    Thread Starter Active Member

    Dec 22, 2017
    800
    70
    Common-ish. There appear to be slightly different voltages. I should probably look into it more.
     
  10. dendad

    Well-Known Member

    Feb 20, 2016
    1,897
    481
    It may be a diode used for the temp reading. Or a thermistor.
     
  11. -live wire-

    Thread Starter Active Member

    Dec 22, 2017
    800
    70
    Better overheat it then to see if that's correct. :rolleyes:
     
Loading...