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AD7768 daisy-chain, datasheet (latest Rev. B 7/2018) inconsistencies

1. Top of page 73 is quoted below, but Figure 109 itself on previous page shows the connections swapped (DOUT0 and DOUT1 to DOUT7 and DOUT6, respectively).  Which version (text or figure) is the correct one?  Which data input pin should be used when AD7768 (8-channel version) is daisy-chained with DOUT0 only: DOUT6 or DOUT7?

2. The datasheet now documents that the FILTER pin should be logic 1 for use with a crystal.  Previous discussion in this forum shows it should be 0 for use with LVDS clock, but that is not mentioned in the datasheet.

Figure 109 shows an example of daisy-chaining
AD7768 devices,
when FORMATx = 01. In this case, the DOUT0 and DOUT1
pins of the AD7768 devices are cascaded to the DOUT6 and
DOUT7 pins, respectively, of the next device in the chain.

[edited by: marekm at 11:01 AM (GMT -4) on 27 Sep 2018]
  •  About 2 years further in time and no solution??

    Are no Analog engineers look at these questions?

    Using the wrong data can result in a wrong PCB which costs a lot of money.

    I am studying this device and it looks promising.

    I will daisy-chain the output with all channels on DOUT0.

    According to figure 109:

    DOUT0 is connected to DOUT7 of the next device.

    DOUT1 is connected to DOUT6 of the next device.

    I only use DOUT0 so logically I assume it is connected to the DOUT7 of the next device.

    However, the text says:

    "Daisy chaining can be achieved in a similar manner on the
    AD7768 and AD7768-4 when using only the DOUT0 pin. In
    this case, only Pin 21 of the AD7768/AD7768-4 is used as the
    serial data input pin."

    Pin 21 is DOUT6.

    So it says DOUT0 is connected to DOUT6 of the next device.

    I NEED CLARIFICATION before I can proceed.

    Thanks, Ton Kuijper

  • Hi Kuijper

    Apologies for the delay in replying, this question has been answered earlier in another similar thread back in 2016

    Please do run thru and let me know if you have any queries

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