Question
For CN0300, could the ADuCM361 be used – in other words implement the
temperature readings and DAC feedback control with just one ADC instead of 2?
Answer
As the circuit is currently built, if one ADC is used for everything, the DAC
output voltage is not stable. The instability occurs when AIN9 is
enabled/disabled as the ADC input channel. When this change occurs, the input
impedance on AIN9 changes due to switches on the input MUX being turned off/on.
When AIN9 is always selected as the input to AIN0 as is the case for this
ADuCM360 implementation, this is not an issue.