The Design of Asynchronous Microprocessor Based on Optimized NCL_X Design-Flow

NCL X circuit is a very efficient way to implement the QDI circuit, which can get all the advantages of the asynchronous circuit, especially the average performance. But the NCL_X circuits suffer from its huge area overhead. To solve this problem, a method for optimizing the complete detection network in the NCL_X circuit has been introduced in this paper. Using this method can dramatically reduced the area of the NCL_X circuit, according to the experimental result, the area of the NCL_X circuit may be reduced more than 60%. We also use this optimized method to implement an asynchronous microprocessor pipeline (APC). Compared to the synchronous implementation, this NCL_X implementation can achieve higher performance because the NCL_X circuit can get the average performance.

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