Research Article Open Access

Source Couple Logic (SCL): Theory and Physical Design

Mohamed Azaga1 and Masuri Othman1
  • 1 VLSI Design Center, Malaysia


This study describes and presents the analysis for the Source-Coupled Logic (SCL) inverter as will as the effect of submicron layout parasitics. The SCL inverter circuit model and its operation is defined. The analysis for the SCL is carried from the point of view of input/output voltage characteristics and the effect of noise margin. The inverter gate delay model is described and the effect of biasing current on the delay is shown. The result shows that, the delay of the SCL inverter is decreased as biasing current increase. The simulation is done based on the 0.18 µ Silterra PDK. Different layouts for SCL inverter have been investigated for its effect on output voltage swing, switching noise and the area. The results show an important effect on the SCL output signals. Post-Simulation was carried out on all proposed layouts using HSPICE and using 0.35 µ MIMOS Berhad PDK. The layout was done using Virtuous from Cadence where as the extraction done using Mentor Graphic-Caliber Interactive tool.

American Journal of Engineering and Applied Sciences
Volume 1 No. 1, 2008, 24-32


Submitted On: 11 August 2008 Published On: 31 March 2008

How to Cite: Azaga, M. & Othman, M. (2008). Source Couple Logic (SCL): Theory and Physical Design. American Journal of Engineering and Applied Sciences, 1(1), 24-32.

  • 7 Citations



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