Let’s assume we have a circuit whose operating ambient temperature range is well-regulated to 25+-5C. Besides cost, what would be the use cases for the different ceramic dielectric types? In other words, what would be the applications is which a specific ceramic dielectric would perform better or worse than others? Can we make any generalizations?
I know that ceramic capacitor letter codes are supposed to indicate temperature dependency of the dielectrics, but is there something more that can be said about it as all of these questions suggest?
- What are Y5V or Z5U capacitors good for?
- Ceramic capacitors microphonic bandwidth
- Do multi-layer ceramic capacitor specifications vary within a dielectric class?
I also know that package size affects the parasitics and thus the resonant frequency and loss of the caps. That some dielectrics are not available in smaller packages and higher voltages, and that many ceramics exhibit piezoelectric/microphonic effects (which ones?). Can all of these factors be condensed in a few rules of thumb?
I have also noticed that manufacturers datasheets seem to assume a specific application for the capacitors, for example by not specifying leakage, resonances, or losses in some of them.
But, if ambient temperature is not a factor, what capacitor would be best for a specific job. Is self-heating an issue for the application/specific type?
All of my commercial circuits so far have not been cost-sensitive, so I just specify X7R, X5R, or NP0 for all ceramic caps, as I see those suggested in IC datasheets. But is there something more than temperature dependency behind those suggestions?
Should I pay more attention to the cap purpose? E.g., use X5R/X7R just for power bypass and regulation, but NPx for anything that is in the signal path? Can any generalization be made, or it is an issue that requires detailed reading of the (very incomplete) manufacturers datasheets?
In short. Are there any general principles that can be applied to simplify searching for parts during a design?