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Title: EMC: Efficient Muller C-Element Implementation for High Bit-width Asynchronous Applications
A Muller C-Element is a digital circuit component used in most asynchronous circuits and systems. In Null Convention Logic, the Muller C-Elements make up the subset of THmn threshold gates where the threshold, m, and the input bit- width, n, are equal. This paper presents a new Efficient Muller C- Element implementation, EMC, that is especially suitable for Null Convention Logic applications with high input bit-widths, and it is much faster and smaller than standard implementations. It has a two-transistor switching delay that is independent of the input bit- width, n, and exhibits low noise and static power consumption. It is suitable for all Muller C-Element applications, especially those like Null Convention Logic register feedback circuits that can have large input bit-widths. To reduce static power consumption, it uses active resistors that are only turned “ON” when necessary. Two output stages are presented to implement the required Muller C- Element digital hysteresis: standard, semi-static cross-coupled inverter version, and differential sense-amplifier option. For large values of n, our circuit requires approximately one-half fewer transistors than combining smaller Null Convention Logic THmn semi-static threshold gates. We have successfully simulated up to n = 1024 at a 65 nm node.  more » « less
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64th IEEE International Midwest Symposium on Circuits and Systems
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National Science Foundation
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