Question
The datadheets recommends not connecting pins 5 and 24 to external active
circuitry. What are the potential risks of connecting pins 5 (DVDD) and pin 24
(AVDD) to external active circuitry (eg 3.3V isolated supply).
Answer
AVDD and DVDD are 2.5V outputs, therefore overdriving these two pins with 3.3V
will reduce the lifetime of the part and can cause performance degradation of
the part that may not be evident immediately. Overdriving these outputs could
also be an issue in terms of communication of the part and could cause errors.
Overall, connecting 3.3V to AVDD and DVDD may seem like it isn’t an issue at
first, but it can cause problems across different ADE7878’s and negatively
affect the lifetime of each part.