Re: AD7714 help


Arlet wrote:
Prakruthi wrote:

Arlet wrote:
Prakruthi wrote:

I have a major problem with the AD7714. I m using channel AIN1 and AIN2
with a gain of 1 for an input that varies between 0.1 to 0.5 V.
I always get an output of 3255255 or 255255255 or 195255255.
Can anybody help me out.

Did you verify the digital interface? Try writing something to a R/W
register (e.g. Filter Low), and see if you can read it back.

Hi Arlet,

Thanks for the brilliant suggestion. I tried to read back something
from the register and I dont get back what I ahve actually written. Do
you know what the problem could be?

If you use a MCU with a SPI peripheral, it could be set to the wrong
SPI mode. Hook up a digital scope or logic analyzer to the SCL,CS#,
DIN,DOUT pins, and compare the diagrams with the data***, make sure
the data gets transferred on the right clock edge. Then try write/read
back again, and look at the interface to see if the correct value is
passed, and then see if this same value makes it all the way to the
application.

Hi,

I did compare the signals with the clock and found out that the data is
not getting transferred on the right clock edge. How do I set the clock
sync right.
How do I determine what the right clock frequency for the SPI transfer
would be.

Thanks for your help.

Regards,
Prakruthi

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