Method of testing phase lock loop status during a Serializer/Deserializer internal loopback built-in self-test

摘要

System and method are implemented to allow phase lock loop (PLL) status testing during a Serializer/Deserializer (SERDES) internal loopback built-in self-test (BIST). An existing pseudo random binary sequence (PRBS) data generator is modified to include a mode that produces a data pattern having a frequency content low enough to be verified on the tester used at the probe.