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Altera_Forum's avatar
Altera_Forum
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11 years ago

BeMicro Max 10 - DAC 5681 Out pin problem

Hello,

this is my first post in this forum, so if I make some kind of mistake, just let me know.

I'm trying to use the DAC AD5681 that comes with the board BeMicroMax 10, but I'm having some problems to find the out pin.

http://www.alteraforum.com/forum/attachment.php?attachmentid=9869&stc=1

I checked the board datasheet and there's no Vout pin, as you can see from the image above

And another strange thing is that I downloaded a template about the FPGA pins and all of the DAC pins are as an output. 


--DAC, 12-bit, SPI interface (AD5681)
  AD5681R_LDACn : out std_logic;
  AD5681R_RSTn : out std_logic;
  AD5681R_SCL : out std_logic;
  AD5681R_SDA : out std_logic;    
  AD5681R_SYNCn : out std_logic;

Just for reference:

https://cloud.altera.com/devstore/platform/14.0.2/bemicro-max-10-kit-baseline-design/ --source of the code template

http://www.alterawiki.com/uploads/b/bc/bemicrom10_getting_started.pdf --source of the image

2 Replies

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    11 years ago

    The Vout pin (which is there - on the AD5681) drives the resulting analogue voltage generated by the DAC. It doesn't connect to the FPGA, only to a test point (TP1) on the board.

    The five pins you list below (from the board datasheet and VHDL template) are all output signals from the FPGA. The DAC has five input signals, which these five FPGA pins drive.

    So, I think you've misunderstood this aspect of the board a little.

    Regards,

    Alex
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    11 years ago

    Thanks for your reply.

    I saw the datasheet of the DAC and I thought the template was wrong, as you said. Because this template was provided by altera, not made by me.

    So I tried to look again in the board and I found where is the pin, there is a big pin with upper case letters DAC_OUT, the problem was the datasheet of the board doesn't talk about that.

    Thank you again, just a begginer mistake.