Common-Mode Noise Suppression of Differential Serpentine Delay Line Using Timing-Offset Differential Signal

In this paper, in order to reduce the common-mode noise, a differential serpentine delay line using the timing-offset differential signal is proposed. The time-domain transmission common-mode noise is greatly reduced from 0.0266 to 0.0126 V, and the time-domain reflection differential-mode noise is maintained the same as compared with the differential serpentine delay line using the zero timing-offset differential signal. Besides, the differential-to-common mode conversion is reduced; the differential-to-differential and differential-to-common mode reflections are kept small. Furthermore, the differential-to-differential mode transmission is maintained the same and the eye diagram is improved. In order to verify the simulation results, scaled up circuits are fabricated and measured where the measurement results are in good agreement with the simulation results.