Hi,
I am using an ADS131E06 converter configured for 4V internal reference and it is powerd by +-2.5V supply. The input signal normally is between +-4V differential voltage symmetrically to Vss.
Sometimes I get strange readings, no idea why.
I use channel 0 which gives me 07 ff ff readings for thousands of samples ==> signal out of range. The status word is c0 00 e0.
Normal sample looks like 0a 1e cb for instance and status word c0 00 e0 (no typo!!!).
What did I expect: Different values of the status word, because the channel 0 of the ADC is not overloaded in the second example and overloaded in the first sample.
Is there anything to setup? I read out of the paper, that the limits for the fault comperators were set to 95% & 5% by default.
Another question: When I am sampling ac signals symmetrical to Vss cause I use +- 2.5V supply, the signal is < 5% of the input range around crossing Vss level. Is the comparator fired in this situation?
Or is the p-input compared to +Vref and the n-input compared to -Vref only to detect signals with a common mode component out of range?
In the moment I get hundreds of thousands correct readings but suddenly the ADC saturates. I measure 3 signals from different sources (different input stages on different PCBs) and if the problem occurs, all three channels give bad readings (saturating, but status info ok).
I have to switch the polarity of my signals and after measuring the reversed signals the channels saturate at 08 00 00. So looks like the signals where out of range and the ADC is working well.
Thanks for helping.
