Transmitter test using phase-lock loop

Various embodiments provide for testing a transmitter using a phase-lock loop, which can be used with a circuit for data communications, such as serializer/deserializer (SerDes) communications. In particular, some embodiments provide for data transmission test of a transmitter by: generating and outputting a pre-determined data pattern through a serializer of the transmitter; sampling a serialized data output of the serializer using a sample clock signal generated by an M/N phase-lock loop (PLL); and using a pattern checker to error check the sampled data to determine whether the data transmission test passes.