540,714 active members*
7,095 visitors online*
Register for free
Login
IndustryArena Forum > CNC Electronics > General CNC Machine Related Electronics > How to test my LM338 to know if it's fake?
Results 1 to 2 of 2
  1. #1

    Join Date
    Mar 2021
    Posts
    1

    How to test my LM338 to know if it's fake?

    Hey guys, I bought some chips from eBay lately, but some of them blow out during using, some works fine, especially the lm338, how to test it to know if its fake, or how do I know if it's broke?
    Btw, does this introduction to lm338 accurate? https://www.apogeeweb.net/circuitry/...regulator.html
    Thanks in advance

  2. #2
    Registered
    Join Date
    Nov 2012
    Posts
    1069

    Re: How to test my LM338 to know if it's fake?

    My guess is that most chips you buy on eBay/AliExpress are of suspicious origin. That's not to say they are "fake" or "bad" - they are usually legitimate products that work perfectly fine.

    How exactly are you using those LM338s? What is your input voltage, output voltage and load current? What are the values of the input/output capacitors? Are there voltage spikes in your circuit? Do the chips get adequate cooling? Those are linear regulators, so they dissipate ALL "unused" V*I as heat.

    The introduction on that website pretty much just quotes the manufacturer's datasheet, so it is accurate.

Similar Threads

  1. Also on Amazon
    By gene8522 in forum UCCNC Control Software
    Replies: 0
    Last Post: 07-25-2018, 08:19 PM
  2. Mdf fake louvered shutters
    By Rdowden65 in forum General WoodWorking
    Replies: 6
    Last Post: 07-24-2017, 08:46 PM
  3. Replies: 18
    Last Post: 09-15-2014, 02:09 PM
  4. Constant Current source LM338
    By dj_nexxus in forum General CNC Machine Related Electronics
    Replies: 3
    Last Post: 07-26-2012, 05:07 AM

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •