Date of Graduation


Document Type


Degree Name

Doctor of Philosophy in Engineering (PhD)

Degree Level



Electrical Engineering


Scott C. Smith

Committee Member

Jia Di

Second Committee Member

Randy Brown

Third Committee Member

Alan Mantooth


Applied sciences, Asynchronous circuit design, Asynchronous vlsi design, Low power vlsi design, Radiation hardened vsli design, Ultra-low power


This dissertation proposes an ultra-low power design methodology called bit-wise MTNCL for bit-wise pipelined asynchronous circuits, which combines multi-threshold CMOS (MTCMOS) with bit-wise pipelined NULL Convention Logic (NCL) systems. It provides the leakage power advantages of an all high-Vt implementation with a reasonable speed penalty compared to the all low-Vt implementation, and has negligible area overhead. It was enhanced to handle indeterminate standby states. The original MTNCL concept was enhanced significantly by sleeping Registers and Completion Logic as well as Combinational circuits to reduce area, leakage power, and energy per operation.

This dissertation also develops an architecture that allows NCL circuits to recover from a Single Event Upset (SEU) or Single Event Latchup (SEL) fault without any data loss. Finally, an accurate throughput derivation formula for pipelined NCL circuits was developed, which can be used for static timing analysis.