Optical Clock Distribution Network using CMOS Single-photon Avalanche Diodes

A new clock distribution network using CMOS single-photon avalanche diodes (SPAD) in combination with free space optics is proposed. The system can work without special implementation of optical waveguides. It consists of an optical source with 660 MHz operation, which in the receiver end is composed of three parallel SPADs biased in quench, hold-off and recharge phases. With the pipeline analogues implementation of SPADs and a logic cell output a 660 MHz clock source can be achieved. The proposed system is post layout simulated in 180nm CMOS technology. The power consumption of 6.74 mW for each SPAD cell, electrical jitter of 237 fs and skew of 43 ps is resulted.