A 6Gbps 1:2 Demultlplexer Design Using Micro Stacked Spiral inductor in CMOS Technology

Micro Stacked Spiral Inductor를 이용한 6Gbps 1:2 Demultiplexer 설계

  • Published : 2008.05.25

Abstract

A 6Gbps 1:2 demultiplexer(DEMUX) IC using $0.18{\mu}m$ CMOS was designed and fabricated. For high speed performance current mode logic(CML) flipflop was used and inductive peaking technology was used so as to obtain higher speed than conventional Current mode logic flipflop. On-chip spiral inductor was designed to maximize the inductive peaking effect using stack structure. Total twelve inductors of $100{\mu}m^2$ area increase was used. The measurement was processed on wafer and 1:2 demultiplexer with and without micro stacked spiral inductors were compared. For 6Gbps data rate measurement, eye width was improved 7.27% and Jitter was improved 43% respectively. Power consumption was 76.8mW and eye height was 180mV at 6 Gbps

CMOS $0.18{\mu}m$ 공정을 이용하여 1.8V supply voltage에서 6Gbps 이상의 처리속도를 가지는 1:2 demultiplexer(DEMUX)를 구현하였다. 높은 동작속도를 위하여 Current mode logic(CML)의 Flipflop을 사용하였으며 추가적인 동작속도 향상을 위하여 On-chip micro stacked spiral inductor($10{\times}10{\mu}m^2$)를 사용하였다. 총 12개의 인덕터를 사용하여 $1200{\mu}m^2$의 면적증가만으로 Inductive peaking의 효과를 나타낼 수 있었다. Chip의 측정은 wafer상태로 진행하였고 Micro stacked spiral inductor가 있는 1:2 demultiplexer와 그것이 없는 1:2 demultiplexer를 비교하여 측정하였다. 6Gbps에서 측정결과 Micro stacked spiral inductor를 1:2 demultiplexer가 inductor를 사용하지 않은 구조보다 Eye width가 약3%정도 증가하였고 또한 Jitter가 43%정도 감소하여 개선효과가 있음을 확인하였다. 소비전력은 76.8mW, 6Gbps에서의 Eye height는 180mV로 측정되었다.

Keywords

References

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