Electronic – Eagle Xref on/off

Why were these packages designed this way?

I can't say for sure why you have the very tiny label on that particular part. Perhaps the idea was to make it "disappear" without deleting it altogether. This allows it to still appear on a BOM, for example.

In general, the value field is not normally used in the silkscreen at all, except maybe in certain educational projects or kits.

Normally, the value field is used only in an assembly drawing, where it just needs to be small enough to match the general size of the part on the drawing.

What is the best way to fix the errors caused by these labels?

As I said above, simply don't include the value field in your silkscreen layer. This is why "names" and "values" have their own layers in the design stack.

Otherwise, it would probably be worth your while to create a custom library that has the labels the way you want them.

What is the best practice to find libraries for Eagle?

• First you must be sure that your device is not in eagle libraries using good search, For example if you want to add 7805 5v regulator, You must search like this: *7805* That because certain manufacturer have their own extension that you don't know.
• If you didn't find your device or reasonable alternative (you can use for example atmega8 device instead of atmega328 device.Try to use famous public libraries produced by:

SparkFun Eagle Lib - AdaFruit Eagle Lib - Dangerous Prototype Eagle Lib - Element14 Eagle Cad Lib Search

• Also a good practice is to memorize if the part you want to use is used in previous open source board, If answer is Yes then go and export used parts there from ULP.

• When you build your own library keep in mind that there is a reference library in eagle called Ref-packages.lib that have most of electronics packages which make create new libraries much easier.

How can I be sure that the library I found is a good quality?

Just print footprint on a paper and make sure that every thing is OK, or you can make sure from eagle that physical footprint is typical to part description from datasheet.