Hi everybody. I've got an ADAU1701, I'd like to use one of auxiliary ADC through MP pins. I read from Datasheet about input circuit to ADC Sigma-Delta but nothing about Aux ADC. Known specifications about Aux ADC full-scale input. Aux-ADC input circuit I realized, has been built with a capcitor and a resistance. Input wave is a 1KHz, 0.5 Vrms sinusoid, but the output wave I get is very damaged.
See the picture attached.
The red wave is DAC out, the blue wave is the Aux_ADC input.
Maybe the input circuit is bad or maybe the low Aux_ADC resolution originates this behavior. I'd like to know why.
Does anybody know how to make an efficient Aux ADC input circuit?
Thanks to all,