C-elements for Hardened Self-timed Circuits
Self-timed circuits are slope sensitive: when the voltage of one input or internal node changes too slowly, the interconnected logical blocks might loose their local one-to-one synchronization. This phenomenon often leads to unwanted global dead-locks of the entire circuit. The deep-submicronic manufacturing process mismatches might create such situations where one logical block is significantly slower than the others. We applied two known solutions for ensuring the correct C-element behavior whatever the slopes are: the transistors are resized and the supply voltage is reduced in order to guarantee the overall chip correctness taking into account the process variations.
KeywordsThreshold Voltage Logical Block NMOS Transistor PMOS Transistor Asynchronous Circuit
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