DC25_PAPER_Track04_High_Speed_and_High_Density_Shen_V3.pdf

1、 Information Classification:General High Speed and High Density Interconnect Using PTFE Material For Flexible PCB Ribbon Cables Dayong Shen Bytedance Chuansheng Cheng Bytedance Luoyi Fang Bytedance Feng Luo Bytedance Scarlet Wang Shengyi Technology Songgang Chai Shengyi Technology Wei Gao Shengyi El

2、ectronics Wei Huang Shengyi Electronics Yosuke Takai Yamaichi Electronics takaiyamaichi.co.jp Gelu Ruijie Networks Information Classification:General Abstract In data center,as ASIC bandwidth increase,data rate and number of lanes of C2M links keep increasing.When PCB cannot meet loss requirements o

3、r ASIC and IO are not on the same board,copper cables are used to connect ASIC to IO instead.It is challenge to arrange a large number cables well and place them close enough to ASIC to reduce PCB loss.Flex or rigid-flex PCB is consider due to its high density,however,higher loss limit its reach dis

4、tance.In this paper,a very low loss OSFP C2M flex ribbon cable is introduced,including material,PCB process,Cable assembly and SI performance.A PTFE material filled with ultra-low loss filler and combined with HVLP4,is used to achieve a loss of around 0.73dB/inch at 53 GHz,which makes it possible to

5、 meet 224G C2M loss requirement.High filler filling is used to achieve low CTE to make PTFE fit in PCB process.In addition,the use of non-glass fabric structure makes the PCB have good bending performance and suitable for C2M Cable application Author(s)Biography Dayong Shen is a high-speed signal sy

6、stem engineer at ByteDance,focusing on high-speed system solutions for data centers.Currently,he has 17 years of working experience in the high-speed signal field.Scarlet Wang is Product Technical Director in Shengyi Technology and has 19 years laminate industry technical support experience.Shes ded