Help Finding a Component

Discussion in 'General Electronics Chat' started by snarf, May 22, 2008.

  1. snarf

    Thread Starter Active Member

    Jun 7, 2007
    56
    0
    I am trying to find this voltage regulator TLVH431 in TO-92 case. I live in Malta and can’t find it locally. I have also searched many UK electronic component stores on the Web but still can’t find it. Does anyone know any UK store which can supply it, or any other store in Europe.

    Thanks.
     
  2. SgtWookie

    Expert

    Jul 17, 2007
    22,182
    1,728
    You might be able to use TL430 or TL431 if your output voltage is >2.5v.

    You might be able to make do with Schottky diodes in series, like 1N5817 through 1N5819, but your regulation won't be nearly as good. A pass transistor could help that.

    Just some "make do" alternative suggestions.
     
  3. snarf

    Thread Starter Active Member

    Jun 7, 2007
    56
    0
    Hi SgtWookie

    Many thanks for your suggestions but unfortunately as far as I know both the TL430 and TL431 will not regulate lower then 2.5V. I need 2V or lower. The TLVH431 has a reference voltage of 1.24V.

    This is a repair job and there is not enough space to make alterations so the only option seems the proper component, but again thanks for your help.
     
  4. thingmaker3

    Retired Moderator

    May 16, 2005
    5,072
    6
  5. snarf

    Thread Starter Active Member

    Jun 7, 2007
    56
    0
    Hi thingmaker3

    Many thanks for link, I have contacted spoerle and asked for the component, now awaiting a reply, will post details when received.
     
  6. bertus

    Administrator

    Apr 5, 2008
    15,638
    2,344
  7. cumesoftware

    Senior Member

    Apr 27, 2007
    1,330
    10
    You could use the LM317. You can set any voltage above 1.25V with a tolerance of 4%. You should use precision resistors to set the voltage.
     
  8. snarf

    Thread Starter Active Member

    Jun 7, 2007
    56
    0

    Hi Bertus,

    Many thanks for link. They also seem to have them in TO-92 package Farnell part number 1575174.

    I have contacted them and await a reply, will post when received.
     
  9. snarf

    Thread Starter Active Member

    Jun 7, 2007
    56
    0

    Hi Cumesoftware,

    Many thanks for advice, the LM317 is a good alternative but unfortunately as I said before there is no space to make alterations and since the size of the LM317 is more then that of the TLVH431 it will not be possible. Furthermore I think that the LM317 will require a heatsink, again space is a problem.
     
  10. SgtWookie

    Expert

    Jul 17, 2007
    22,182
    1,728
    Take a look at an LM317LZ - it's in a TO-92 package. If you didn't need a heatsink with your TLVH431, you won't need one with the LM317LZ either.
    The TLVH431 requires a pair of resistors to set the output voltage; so does the LM317LZ.
    The biggest problems I can think of is:
    1) The voltage differential between input and output is 1.7v. Your supply would have to be at least that much higher above the desired output voltage.
    2) The TLVH431 is a shunt limiter, the LM317LZ is a series regulator. You would have to cut traces.
    3) The LM317LZ would not react as the TLVH431 would to a rise in the output voltage
     
  11. redacejr

    Active Member

    Apr 22, 2008
    85
    0
    aw ras jien malti wkoll
    "hey dude im maltese too.

    add me msn cybermarlon5@hotmail.com
    i usually go to geelectronics in birkirkara .

    i checked if they have tlvh431 but they dont. i dont think they have 3-terminal adjustable voltage references. if not try NPN-base-diode series. or the 1.22 volt regulator . thats till where i can help you sorry =S
     
    Last edited: May 26, 2008
  12. snarf

    Thread Starter Active Member

    Jun 7, 2007
    56
    0


    Hello again SgtWookie,

    Once again thank you for your valued advice, it's another good option to consider.

    See post of solution further on.
     
  13. snarf

    Thread Starter Active Member

    Jun 7, 2007
    56
    0

    Hi redacejr,

    Nice to meet another Maltese. I did check with G&E and all the others in Malta, none have it. I didn't even manage to find it at UK stores. Thanks for you advice and help.

    Which NPN-base-diode series and which 1.22 volt regulator are you referring to?

    See post of solution further on.
     
  14. snarf

    Thread Starter Active Member

    Jun 7, 2007
    56
    0
    I would like to thank all of you that offered me all the advice and help and also everyone else on All About Circuits. Following is the latest development to me question.

    As regards Spoerle, they have not replied. It seems like they don't deal with private people.

    As regards to Farnell, they have informed me that they are represented in Malta by International Oilfield Supplies Ltd. They can supply the component at a reasonable additional cost. Therefore I have ordered some TLVH431 in TO-92 and should have the components in hand in two weeks time.

    I have appreciated all the options suggested and also learned something from them and also that many other similar voltage regulators are available.

    Although my problem seems to have been solved I will still appreciate any other advice and possible solutions.

    Once again many thanks to everyone.
     
Loading...