A 2.5Gb/s 2:1 Multiplexer Design Using Inductive Peaking in $0.18{\mu}m$ CMOS Technology

Micro spiral inductor를 이용한 2.5Gb/s급 2:1 Multiplexer 설계

  • Published : 2007.08.25

Abstract

A 2.5Gb/s 2:1 multiplexer(MUX) IC using $0.18{\mu}m$ CMOS was designed and fabricated. Inductive peaking technology was used to improve the performance. On-chip micro spiral inductor was designed to maximize the inductive peaking effect without increasing the chip area much. The designed 4.7 nH micro-spiral inductor was $20\times20{\mu}m2$ in size. 2:1 MUX with and without micro spiral inductors were compared. The rise and fall time was improved more than 23% and 3% respectively using the micro spiral inductors for 1.25Gb/s signal. For 2.5 Gb/s signal, fall and rise time was improved 5.3% and 3.5% respectively. It consumed 61mW and voltage output swing was 1$180mV_{p-p}$ at 2.5Gb/s.

[ $0.18{\mu}m$ ] CMOS공정을 이용하여 supply voltage 1.8V에서 2.5Gb/s 이상의 데이터 처리속도를 가지는 2:1 Multiplexer(MUX) 설계를 하였다. High speed 동작을 위한 주파수의 한계를 극복하기 위해서 4.7 nH의 on-chip micro spiral micro inductor $(20\times20{\mu}m2)$가 설계 되었고, 10개 이상의 inductor를 사용하고도 칩 면적 증가가 거의 없으면서 inductive peaking 효과를 극대화할 수 있었다. 칩 측정은 on-wafer로 진행되었고, micro spiral inductor가 있는 2:1 MUX와 그것이 없는 2:1 MUX 각각 측정하여 그 결과를 비교하였다. 측정결과 micro spiral inductor를 가진 2:1MUX가 rise time과 fall time이 1.25Gb/s에서는 rise time이 23%, fall time은 3%의 peaking 개선 효과가 있는 것을 확인하였다. 2.5Gb/s에서는 fall time이 약 5.3%, rise time 3.5%의 개선 효과를 보았다. 전체 소비전력은 61.2mW, 2.5Gb/s에서 voltage output swing은 $180mV_{p-p}$로 측정되었다.

Keywords

References

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