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Visitor II
July 19, 2004
Question

How to read stable a/d converter value? Can any ST engineer give me some advice?thanks!

  • July 19, 2004
  • 6 replies
  • 1126 views
Posted on July 20, 2004 at 00:14

How to read stable a/d converter value? Can any ST engineer give me some advice?thanks!

    This topic has been closed for replies.

    6 replies

    wdcaiAuthor
    Visitor II
    May 17, 2011
    Posted on May 17, 2011 at 12:02

    Visitor II
    May 17, 2011
    Posted on May 17, 2011 at 12:02

    Please send your question to

    mailto:apps.psd@st.com

    . Provide information about the board you are using (DK3200 or your own), version # if DK3200, oscillator frequency, your settings, what voltage you are measuring, what reading you expect and what you are getting, and anything else that you think is relative.

    Also provide the following information so we know a little more about you:

    Name

    Company Name

    Phone Number

    Location (City, State, Country)

    Production uPSD part number (3233, 3234, etc.)

    Application

    Projected annual volume (units)

    Production start date

    Thanks,

    uPSD Applications Engineering

    wdcaiAuthor
    Visitor II
    May 17, 2011
    Posted on May 17, 2011 at 12:02

    I have written am email about a/d problem to ST technical support,I am looking forward to his reply,thanks!

    Visitor II
    May 17, 2011
    Posted on May 17, 2011 at 12:02

    hi

    You can''t get a stable A/D reading. There is a prblem in same version of uPSD.

    Visitor II
    May 17, 2011
    Posted on May 17, 2011 at 12:02

    uPSD3334 Rev C silicon is now available and is errata free. Rev A has some accuracy issues when using the prescaler. If you limit the MCU clock to 16MHz and use an ADC prescaler divisor of ''1'', you should be able to achieve +-2 LSB, otherwise the accuracy will be around +-4 LSB.

    Rev A silicon has date codes of 5A5010332, 5A5010338, 5A5010345. Please contact your local sales representative or distributor to obtain rev C samples.

    If you have a DK3300 with rev A silicon, please send a request for an updated board with rev C silicon to

    mailto:apps.psd@st.com

    . Be sure to include:

    Name

    Company Name

    Phone Number

    Shipping Address

    (Address, City, State, Country)

    Production uPSD part number (3333, 3334, etc.)

    Application

    Projected annual volume (units)

    Production start date

    Thanks,

    uPSD Applications Engineering

    wdcaiAuthor
    Visitor II
    May 17, 2011
    Posted on May 17, 2011 at 12:02

    Rev C silicon is used iin my project, and OSC is 18.432Mhz, I modified the turbo_upsd.h provided by ST,But the accuracy is about +/- 20 LSB ,not +/-2 Lsb, in fact , I want to know why upsd33xx can't provide separate analog ground and Vcc, how to deal with ground pins in Upsd while layout. All ground pins can be connected with a ground plane and don't need think about analog and digital ground?

    Thanks!