Testing embedded building blocks is much more
difficult than testing their stand-alone counterparts, and
usually this cannot be done by replicating conventional
testing techniques. In mixed-signal ICs, the most
affected components are the analog cores, since analog
testing is based on checking functional specifications,
which can be conflictive when the test time has to be
kept short, the number of available pins is reduced and
full access to inputloutput core terminals cannot be
granted.