From 664ec7412576bc7e756c407574e1a1f73f3d3c95 Mon Sep 17 00:00:00 2001 From: Holger Dengler Date: Tue, 9 Oct 2012 11:49:22 +0200 Subject: Flash-Memory: new Technology presentation This new technology presentation describes the Flash-Memory technology, the functional principles and the side effects. It can be used as an introduction to a one-day session about Flash-Memory and Flash-Filesystems. Signed-off-by: Holger Dengler --- flash-memory/technology/pres_technology_en.tex | 181 +++++++++++++++++++++++++ 1 file changed, 181 insertions(+) create mode 100644 flash-memory/technology/pres_technology_en.tex (limited to 'flash-memory/technology/pres_technology_en.tex') diff --git a/flash-memory/technology/pres_technology_en.tex b/flash-memory/technology/pres_technology_en.tex new file mode 100644 index 0000000..546a1be --- /dev/null +++ b/flash-memory/technology/pres_technology_en.tex @@ -0,0 +1,181 @@ +\def\lximg{/usr/share/lx/icons/fueller.png} + +\input{configpres} + +\subsection{Technology} + +\title{Flash-Memory Technology} +\maketitle + +\def\lximg{none} + +\begin{frame} +\frametitle{Contents} +\tableofcontents +\end{frame} + +\subsubsection{Structure and Function} +\begin{frame}[fragile] +\frametitle{Single Cell Structure} +\begin{itemize} +\item Base element: MOSFET with a floating gate (FGMOS) +\item Organization of cells in blocks and pages +\end{itemize} +\begin{figure}[h] +\centering +\includegraphics[scale=0.5]{images/fmtech-fgmos.png} +\end{figure} +\end{frame} + +\begin{frame}[fragile] +\frametitle{Read} +\begin{figure}[h] +\centering +\includegraphics[scale=0.4]{images/fmtech-single_read.png} +\end{figure} +\end{frame} + +\begin{frame}[fragile] +\frametitle{Write (Program)} +\begin{figure}[h] +\centering +\includegraphics[scale=0.4]{images/fmtech-single_program.png} +\end{figure} +\end{frame} + +\begin{frame}[fragile] +\frametitle{Erase} +\begin{figure}[h] +\centering +\includegraphics[scale=0.4]{images/fmtech-single_erase.png} +\end{figure} +\end{frame} + +\subsubsection{Flash-Memory Types} +\begin{frame}[fragile] +\frametitle{Overview} +\begin{itemize} +\item NOR +\item NAND +\item Single- and Multi-Level Cells +\end{itemize} +\end{frame} + +\begin{frame}[fragile] +\frametitle{NOR} +\begin{itemize} +\item direct addressable +\item usable like RAM/ROM (direct attach to CPU) +\item pros: + \begin{itemize} + \item fault tolerant + \item high write-rate for small data + \end{itemize} +\item cons: + \begin{itemize} + \item low data density (multiple gates per bit) + \item low write-rate for large data + \item cost + \end{itemize} +\end{itemize} +\end{frame} + +\begin{frame}[fragile] +\frametitle{NAND} +\begin{itemize} +\item matrix organization (blocks and pages) +\item addressing via controller logic +\item pros: + \begin{itemize} + \item cost + \item high data density (1 to many bits per gate) + \item high read-/write-rate for large data + \item no layout change in hardware for more capacity + \end{itemize} +\item cons: + \begin{itemize} + \item large effort for extensive Error Correction Codes (ECC) + \end{itemize} +\end{itemize} +\end{frame} + +\begin{frame}[fragile] +\frametitle{Data density} +\begin{itemize} +\item Single-Level Cells (SLC) + \begin{itemize} + \item ca. 100,000 write/delete cycles + \item pros: + \begin{itemize} + \item robust + \item low Error Correction Code (ECC) effort + \end{itemize} + \item cons: + \begin{itemize} + \item low data density + \end{itemize} + \end{itemize} +\end{itemize} +\pause +\begin{itemize} +\item Multi-Level Cells (MLC) + \begin{itemize} + \item ca. 3,000 to 10,000 write/delete cycles + \item pros: + \begin{itemize} + \item high data density + \end{itemize} + \item cons: + \begin{itemize} + \item expensive Error Correction Codes (ECC) like BCH + \item wear prone + \item low read-rate + \end{itemize} + \end{itemize} +\end{itemize} +\end{frame} + +\subsubsection{NAND block operations and side effects} +\begin{frame}[fragile] +\frametitle{Read} +\begin{figure}[h] +\centering +\includegraphics[width=10cm]{images/fmtech-read.png} +\end{figure} +\end{frame} + +\begin{frame}[fragile] +\frametitle{Read Disturb} +\begin{figure}[h] +\centering +\includegraphics[width=10cm]{images/fmtech-read_disturb.png} +\end{figure} +\end{frame} + +\begin{frame}[fragile] +\frametitle{Write} +\begin{figure}[h] +\centering +\includegraphics[width=10cm]{images/fmtech-write.png} +\end{figure} +\end{frame} + +\begin{frame}[fragile] +\frametitle{Write Disturb} +\begin{figure}[h] +\centering +\includegraphics[width=10cm]{images/fmtech-write_disturb.png} +\end{figure} +\end{frame} + +\subsection{} +\begin{frame} +\frametitle{References} +\begin{thebibliography}{99} +% \bibitem{FLASHMEM} David Woodhouse. Presentation \emph{Flash Memory}, 2012. http://david.woodhou.se/dwmw2-kr-2012-09.odp +\bibitem{FLASHMEM} David Woodhouse. Presentation \emph{Flash Memory}, 2012. +\href{http://david.woodhou.se/dwmw2-kr-2012-09.odp}{http://david.woodhou.se/dwmw2-kr-2012-09.odp} +\end{thebibliography} +\end{frame} + +\input{tailpres} -- cgit v1.2.3