I have a problem using AD7888 with ATmega324PA.
I am measuring sine voltages f=50Hz, so T= 20ms on 6 channels, 7 and 8 AIN are connected to GND
SPI frequency is 125kHz and SPI mode is 3.
What happens is that from time to time I get one spike in measurements.
I preform 72 measurements to cover time frame of T=20 ms. I'm interested in max. values and e.g. on 1st channel I have max of 600 and one spike happens with value 1500 and this spike is not present in signal which I measure.
What could you suggest me to do?
Thank you in advance !