High speed current-mode signaling circuits for on-chip interconnects

As the technology scales, the global wire delay becomes a major bottleneck in realizing high performance SOCs. Apart from the technological efforts being made to overcome this problem, it is necessary to develop new circuit design techniques. This paper presents three current-mode circuits for high-speed signal propagation across long on-chip busses. Theoretical analysis has shown that a factor of three can be gained in propagation delay when current-mode (CM) signaling is used in comparison to voltage-mode (VM). In this paper, we show that the delay is reduced by more than a factor of 2 in current mode signaling by using the circuit techniques we propose in comparison to voltage-mode signaling in 0.13 /spl mu/m CMOS technology. This is without any significant power penalty. Further gains in speed are achieved at very high power consumption. The power dissipation on on-chip busses is a strong function of bus layout and data rate. We identified data rates for which the proposed current mode signaling circuits become more power efficient compared to voltage mode signaling circuits.

[1]  Evert Seevinck,et al.  Current-mode techniques for high-speed VLSI circuits with application to current sense amplifier for CMOS SRAM's , 1991 .

[2]  Wayne Burleson,et al.  Current sensing techniques for global interconnects in very deep submicron (VDSM) CMOS , 2001, Proceedings IEEE Computer Society Workshop on VLSI 2001. Emerging Technologies for VLSI Systems.

[3]  George Varghese,et al.  Low-swing on-chip signaling techniques: effectiveness and robustness , 2000, IEEE Trans. Very Large Scale Integr. Syst..

[4]  A. Katoch,et al.  Fast signal propagation for point to point on–chip long interconnects using current sensing , 2002, Proceedings of the 28th European Solid-State Circuits Conference.

[5]  Hoi-Jun Yoo,et al.  A 51mW 1.6GHz on-chip network for low-power heterogeneous SoC platform , 2004, 2004 IEEE International Solid-State Circuits Conference (IEEE Cat. No.04CH37519).

[6]  S. Wong,et al.  Near speed-of-light signaling over on-chip electrical interconnects , 2003 .

[7]  Kwyro Lee,et al.  High speed and low swing interface circuits using dynamic over-driving and adaptive sensing scheme , 1999, ICVC '99. 6th International Conference on VLSI and CAD (Cat. No.99EX361).