AD1854: SPI port unused

Document created by analog-archivist Employee on Feb 23, 2016
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At this moment I’m working at a prototyping-project in which I use a DA
converter of Analog Devices. The DAC in question is the AD1854KRS.
I’ve downloaded the datasheet from your website. In my project I have no
interest in controlling the DAC using the SPI-port. According to the datasheet
this should be possible. My question is what to do with the SPI-pins of the
DAC, namely CLATCH, CCLK and CDATA. At this moment they are connected to the
digital-ground. Is this correct, or should those connected to VCC or may those
pins left floating? I can’t find the necessary information in the datasheet. I
would appreciate if you could answer these question.


If the SPI port is unused on the AD1854, it is preferred that CLATCH be tied to
digital +5V and CDATA and CCLK be tied to digital ground.  It is, however, also
OK to tie CLATCH to digital ground in this case.  Unused inputs should not be
left floating.