Problems with AD7091

Good day! I have several questions about AD7091.

1) How to make a software reset correctly? We are thinking that documentation is written not so accurate in some points.

2) What exactly will be with AD7091 if we won’t do software reset?

3) Additionally, it is necessary to clarify the operation of the SPI in the program reset mode. We use SPI mode 0 (CPOL = 0, CPHA = 0). Is it OK? Or polarity of SCK should be CPOL = 1 (as in the figure)? Accordingly what phase of CPHA should be?

4) We observed the following situation. We use the AD7091 for the analog input, when specifying the current at the input, the ADC chip gave out the code: at 4mA = BA4_hex, at 12мА= 684_hex, at 20мА=165_hex (when the failure occurred), then after a short time after the power reset AD7091 gave out the code 4mA = 290_hex, 12mA = 7B0_hex, 20mA = CD0_hex. It is necessary to clarify whether this is possible, and what will happen if we do not do the correct software reset?

Additionally, we have oscillograms how we make software reset: yellow CONVST, blue CS, pink SDO, green SCLK.

Also we have a video with failure.

Thank you in advance for your response!

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    •  Analog Employees 
    on Aug 24, 2018 12:51 PM
    This question has been assumed as answered either offline via email or with a multi-part answer. This question has now been closed out. If you have an inquiry related to this topic please post a new question in the applicable product forum.

    Thank you,
    EZ Admin
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  • 0
    •  Analog Employees 
    on Aug 24, 2018 12:51 PM
    This question has been assumed as answered either offline via email or with a multi-part answer. This question has now been closed out. If you have an inquiry related to this topic please post a new question in the applicable product forum.

    Thank you,
    EZ Admin
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