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@ -101,9 +101,15 @@ of length to this number, to a total of roughly $2200\lambda$.
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\pagebreak
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\section{Performance Results}
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I was able to clock my design at $1.9\textit{ns}$.
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I was able to clock my design at \textbf{$1.3\textit{ns}$}.
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%
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Two factors lead to these upper limits.
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I realize that this isn't as fast as everyone else, but I ask that you take
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into consideration the fact that \textbf{I was working with the old wire model}
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until about an hour before the final due date (since I didn't know the wire model changed).
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If I knew earlier, I'd have more time to optimize my design for the timings associated
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with the new model.
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%
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Two factors lead to this upper limit.
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%
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\begin{itemize}
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\item \textit{Write capacitance} makes it increasingly difficult to overwrite the value
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@ -353,6 +359,27 @@ space incurred, an entire column is approximately $100\lambda$ wide.
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\label{fig:layout-arrayed}
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\end{figure}
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\pagebreak
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\section{Further Design Ideas}
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I discovered -- from other people in the class -- that an 8-column design was plausible.
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Unfortunately, I was only convinced a day or so before the project was due, which did not give me
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enough time to redesign my SRAM. I have seen students successfully using
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the 8-column design by sharing \textsc{Wl} wires for each 'row', and using
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the remaining 3 bits to enable and disable the write block. Since reading does
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not change the cell value, this is a viable approach; all 8 columns would ``read''
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(except during writing, in which 7 columns would read and 1 would write). As
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long as a proper address selection mechanism is implemented into the read collector
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circuit (which at present cannot handle concurrent reads), this would work just
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fine, albeit at the expense of added power consumption (from draining and re-charging
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7 extra wires). This design, combined with my idea of placing the write block
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in the middle of the column, can lead to very short effective wire lengths. If
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I was to approach this project again, that's what I would try.
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\section{Acknowledgements}
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Reed's aforementioned idea of sharing well contacts between adjacent cells
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played a part in my design. Also, without the other students in the class
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Discord, I would not have known to use the ``better'' wire model at all.
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\pagebreak
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\bibliographystyle{unsrt}
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\bibliography{bibliography}
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