Abstract:
A phase locked loop includes a voltage controlled oscillator including a plurality of delay cells configured to respectively generate a plurality of clock signals having different phases and a harmonic lock detector configured to detect harmonic lock in the voltage controlled oscillator and to generate a reset signal in response. Remaining ones of the delay cells other than a first delay cell among the plurality of delay cells are reset in response to the reset signal.
Abstract:
A termination circuit is provided. The termination device includes terminals configured to receive a corresponding signal; unit circuits respectively connected to the terminals, the unit circuits each including a unit resistor and a unit switch element connected to each other in series; common mode capacitors; first switch elements respectively connected between each of the unit circuits and a first corresponding common mode capacitor of common mode capacitors, each of the first switch elements being configured to turn on when the corresponding signal is received in a first mode; and second switch elements respectively connected between each of the unit circuits and a second corresponding common mode capacitor of the common mode capacitors, the second switch elements being configured to turn on when the corresponding signal is received in a second mode different from the first mode.
Abstract:
A clock data recovery circuit including: a digital phase detector and deserializer configured to sample serial data using a recovery clock signal to generate an up phase error signal and a down phase error signal which correspond to a phase difference between the serial data and the recovery clock signal; a digital loop filter configured to generate an up fine code and a down fine code based on a result of counting the up and down phase error signals; a loop combiner configured to generate an up fine tuning code and a down fine tuning code by using the up and down phase error signals and the up and down fine codes; and a digitally controlled oscillator configured to generate the recovery clock signal having a frequency changed with the up and down fine tuning codes.
Abstract:
A phase locked loop includes a voltage controlled oscillator including a plurality of delay cells configured to respectively generate a plurality of clock signals having different phases and a harmonic lock detector configured to detect harmonic lock in the voltage controlled oscillator and to generate a reset signal in response. Remaining ones of the delay cells other than a first delay cell among the plurality of delay cells are reset in response to the reset signal.