TY - GEN
T1 - Robust design of high fan-in/out subthreshold circuits
AU - Chen, Jinhui
AU - Clark, Lawrence T.
AU - Cao, Yu
PY - 2005
Y1 - 2005
N2 - Operating CMOS circuits with power supplies below the threshold voltage has been suggested for ultra-low power systems. High fan-in or fan-out circuits, such as those in memories, are prone to failure when operating in this regime. Vanishing noise margins due to reduced transistor on-to-off current ratios result in circuit failure as the supply voltage shrinks. Therefore, design guidelines for robust subthreshold logic circuit are developed in this paper. First, an analytical model is derived to determine a circuit's fan-in/out limitations and the minimum supply voltage for robust subthreshold operation. Excellent agreement between the analytical model and circuit simulations is shown. This model is applied to the analysis of circuit robustness as affected by design choices, both systematic and random processing variations, supply voltage fluctuations, and temperature variations.
AB - Operating CMOS circuits with power supplies below the threshold voltage has been suggested for ultra-low power systems. High fan-in or fan-out circuits, such as those in memories, are prone to failure when operating in this regime. Vanishing noise margins due to reduced transistor on-to-off current ratios result in circuit failure as the supply voltage shrinks. Therefore, design guidelines for robust subthreshold logic circuit are developed in this paper. First, an analytical model is derived to determine a circuit's fan-in/out limitations and the minimum supply voltage for robust subthreshold operation. Excellent agreement between the analytical model and circuit simulations is shown. This model is applied to the analysis of circuit robustness as affected by design choices, both systematic and random processing variations, supply voltage fluctuations, and temperature variations.
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U2 - 10.1109/ICCD.2005.96
DO - 10.1109/ICCD.2005.96
M3 - Conference contribution
AN - SCOPUS:33747042922
SN - 0769524516
SN - 9780769524511
T3 - Proceedings - IEEE International Conference on Computer Design: VLSI in Computers and Processors
SP - 405
EP - 410
BT - Proceedings - 2005 IEEE International Conference on Computer Design
T2 - 2005 IEEE International Conference on Computer Design: VLSI in Computers and Processors, ICCD 2005
Y2 - 2 October 2005 through 5 October 2005
ER -