A circuit includes phase detection, frequency adjustment, sampler, and control circuits. The phase detection circuit compares phases of first and second periodic signals to generate a control signal. The frequency adjustment circuit adjusts a frequency of the second periodic signal and a frequency of a third periodic signal based on the control signal. The sampler circuit samples a data signal to generate a sampled data signal in response to the third periodic signal. The control circuit adjusts the frequency of the third periodic signal based on the data signal changing from a first data rate to a second data rate while maintaining the frequency of the second periodic signal constant. The control circuit adjusts the frequency of the second periodic signal and the frequency of the third periodic signal based on the data signal changing from the second data rate to a third data rate.