Patent ID: 11921158
Assignee: SAMSUNG ELECTRONICS CO., LTD.
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 18:
19. An operating method of a fan-out buffer which includes a first channel including a first delay circuit configured to adjust a first delay time of a calibration test signal depending on a first delay control signal and a second channel including a second delay circuit configured to adjust a second delay time of the calibration test signal depending on a second delay control signal, the method comprising:
detecting an edge included in a first time domain reflectometry (TDR) waveform on an output terminal of the first channel to generate a first start pulse signal including a first pulse;
detecting an edge included in a second TDR waveform on an output terminal of the second channel to generate a second start pulse signal including a second pulse;
generating a stop pulse signal including a first stop pulse by performing an AND operation on the first pulse and the second pulse; and
calculating a first phase difference between the first pulse and the first stop pulse and generating the first delay control signal by using a calculation result such that a skew between the first pulse and the second pulse is calibrated.