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ADS1232: Is this TI board legit?

Part Number: ADS1232

I am very interesting in using the ADS1232 for load cells and find the detail required to make a quality board exceeds me.  I do software for a reason.

I ran across this board on a marketplace web site and it seems like a good deal.  About $24USD, and it's made by TI!!

Or is it?  I can't find any documentation or reference to this board outside of a few chinese web shops who all sell the same thing.  Did Texas Instruments make this board?  If so, where can I find documentation on it.  It looks real, I just can't find supporting info.

    

What is the story here?   Where can I get them in North America?

  • ...and another thing.   The crystal on this board looks like it is stamped as 4.000 MHz on the top of the case.   The data sheet references using 4.9152 MHz.   I assume the basic ADC function will work but all the timings will be shifted for the digital filters.  How does 50 Hz and 60 Hz rejection look if you use the ADS1232 with a 4 MHz crystal?  Wouldn't we get about 20% less measurements per second with a slower crystal?   Why would a board built by TI use a value not recommended in the data sheet?   There are no specs on crystal frequency in the data sheet, other than the references to use 4.9152 MHz.


  • Hi Dave,

    This appears to be an interesting board, but the board is not from TI.  Apparently the board manufacturer used the TI logo without permission.

    In most cases you would use the internal oscillator as opposed to the external one.  As you surmised, using a different frequency from the nominal will affect the output data rate as well as the filter notches.  From the documentation for the board you are inquiring about there would be no 50/60 Hz rejection anyway as the board is set to use 80sps and not the 10sps data rate. 

    Best regards,

    Bob B

  • Thanks for the reply.  It looks like a real TI product, except a few small little details here and there that made me ask.  The big item was lack of online documentation.  TI does nothing if not produce literature, app notes, and white papers.  I'm not complaining, I like it and was suspicious when it was missing.

    I didn't see anywhere in the description to say it was strapped for 80sps only.  I would assume it can be changed via shorting wire or something.  Have you had any prior experience with this particular board?   Please keep in mind, I haven't yet read the complete web description for all available vendors for this board.  You may have seen documentation that the web store I reviewed didn't mention.

    In the end, I don't really care who makes it as long as it has the features I want, at a price I can afford, and is available.  All other things being equal, I don't mind having to cut a trace to disable the external crystal.  It's much better at the layout than the cheapo boards on amazon that just expand the chip pinout to 0.1" spacing.  I mean, who puts a shield can on the thing unless they know it is needed?  (which, it probably is).

    The whole lack of 10sps and lack of 50/60 Hz filtering would be a problem for me.  I don't need samples at 80sps if they are noisy.  I'm hoping to get around 40 to 50,000-ish usable counts.  I tried some of the low end ADS1232 boards and all I could get was about 7500.

    If you have any other suggestions for boards that can drive a load cell and convert to some digital format, I would appreciate hearing about them.  I don't mind paying for features but I don't need a $200 eval board that comes with a bunch of processors and LEDs.  I want the analog layout and signal handling done properly and this board (on the surface) looks like someone spent more than 2 minutes reading the TI data sheet.   I mean, you guys publish the recommended layout, all a designer has to do is slap it on a board and add appropriate connectors and minimal eco-system support.  I don't have a problem connecting to three digital GPIO lines and using them to harvest the data myself.

  • Hi Dave,

    TI cannot endorse or confirm how well this board performs as it is designed by TI.  In fact, we were not knowledgeable of this board until you brought it to our attention.  TI will not support this board as to operation or performance.  From the picture it does appear that the SPEED setting is selectable.

    It is not a trivial task getting high performance from a prototyping solution.  Any external wiring will add noise pickup (EMI/RFI) as the wiring will act as an antenna.  To get an idea of potential capability we have a Bridge Calculator tool in the free/downloadable Analog Engineers Calculator.  In the calculator you can enter the desired operating parameters and you can then calculate whether or not a specific device will even work for you.

    We are currently working on a bridge cookbook which will give basic guidance on designing systems such as weigh scales.  We hope to have this available sometime in the fall.

    Best regards,

    Bob B