git scare and then a typo in tikz arrghhhh
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@ -201,6 +201,7 @@ a {\bcfm} and not investigate other possibilities.
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From the deficiencies outlined above, ideally we can form a wish list for a better methodology.
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{ \small
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\begin{itemize}
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\label{fmmdreq}
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\item Address the state explosion problem.
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\item Ensure that all component failure modes be considered in the model.
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\item Be easy to integrate mechanical, electronic and software models \cite{sccs}[pp.287].
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@ -424,7 +425,7 @@ We can now represent a resistor in terms of its failure modes as a directed acyc
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\caption{DAG representing a reistor and its failure modes}
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\label{fig:rdag}
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\end{figure}
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%}
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%}section
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%{
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%}
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Thus or the potential divider in the circuit in figure~\ref{fig:pd},
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@ -442,6 +443,47 @@ Modelling the two resistors as a functional group, we present this as a directed
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%in the potential divider, shown
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in figure \ref{fig:fg1dag}.
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\begin{figure}[h+]
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\centering
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\begin{tikzpicture}[shorten >=1pt,->,draw=black!50, node distance=\layersep]
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\tikzstyle{every pin edge}=[<-,shorten <=1pt]
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\tikzstyle{fmmde}=[circle,fill=black!25,minimum size=30pt,inner sep=0pt]
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\tikzstyle{component}=[fmmde, fill=green!50];
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\tikzstyle{failure}=[fmmde, fill=red!50];
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\tikzstyle{symptom}=[fmmde, fill=blue!50];
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\tikzstyle{annot} = [text width=4em, text centered]
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\node[component] (R1) at (0,-4) {$R_1$};
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\node[component] (R2) at (0,-6) {$R_2$};
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\node[failure] (R1SHORT) at (\layersep,-2) {$R1_{SHORT}$};
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\node[failure] (R1OPEN) at (\layersep,-4) {$R1_{OPEN}$};
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\node[failure] (R2SHORT) at (\layersep,-6) {$R2_{SHORT}$};
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\node[failure] (R2OPEN) at (\layersep,-8) {$R2_{OPEN}$};
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\path (R1) edge (R1SHORT);
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\path (R1) edge (R1OPEN);
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\path (R2) edge (R2SHORT);
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\path (R2) edge (R2OPEN);
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% Potential divider failure modes
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%
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% \node[symptom] (PDHIGH) at (\layersep*2,-4) {$PD_{HIGH}$};
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% \node[symptom] (PDLOW) at (\layersep*2,-6) {$PD_{LOW}$};
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%
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% \path (R1OPEN) edge (PDHIGH);
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% \path (R2SHORT) edge (PDHIGH);
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%
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% \path (R2OPEN) edge (PDLOW);
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% \path (R1SHORT) edge (PDLOW);
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\end{tikzpicture}
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\caption{Component Failure Modes of the `Potential Divider'}
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\label{fig:fg1dag}
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\end{figure}
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We can now look at each of these base component failure modes,
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@ -577,9 +619,9 @@ we can use it
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as a building block for other {\fgs}.% in the same way as we used the resistors $R1$ and $R2$.
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Note that number of base failure modes, four, is reduced to two in the {\dc}.
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Not only have we avoided the state explosion problem of having to
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check $R1$ and $R2$ against all other components in the system they may belong to,
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by making it a derived component, we have reduced the number of errors we need to consider at higher levels
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We avoided the state explosion problem of having to
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check $R1$ and $R2$ against all other components in the system they may belong to.
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Also, by modularising the circuit as a {\dc}, we have reduced the number of errors we need to consider at higher levels
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of analysis.
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% \subsection{Re-Factoring the UML Model}
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%
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@ -643,7 +685,7 @@ of analysis.
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%By applying the methodology in section \ref{fmmdproc}, the wishlist can
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%now be evaluated for the proposed FMMD methodology.
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We can now evaluate the FMMD method using the criteria in section \ref{fmmdproc}.
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We can now evaluate the FMMD method using the criteria in section \ref{fmmdreq}.
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{ \small
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\begin{itemize}
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@ -682,12 +724,12 @@ for all SYSTEM failure modes.
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The minimal cuts sets for the SYSTEM level failures can have computed MTTF
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and danger evaluation statistics sourced from the component failure mode statistics \cite {mil1991}.
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\item{ It should be easy to use, ideally
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using a graphical syntax (as opposed to a formal mathematical one).}
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A modified form of constraint diagram (an extension of Euler diagrams) has
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been developed to support the FMMD methodology.
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This uses Euler circles to represent failure modes, and spiders to collect symptoms, to
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advance a {\fg} to a {\dc}.
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% \item{ It should be easy to use, ideally
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% using a graphical syntax (as opposed to a formal mathematical one).}
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% A modified form of constraint diagram (an extension of Euler diagrams) has
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% been developed to support the FMMD methodology.
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% This uses Euler circles to represent failure modes, and spiders to collect symptoms, to
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% advance a {\fg} to a {\dc}.
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\item{ From the top down the failure mode model should follow a logical de-composition of the functionality
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@ -724,7 +766,7 @@ particular field. It can be applied to mechanical, electrical or software domain
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It can therefore be used to analyse systems comprised of electrical,
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mechanical and software elements in one integrated model.
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\today
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%\today
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%
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{ \small
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\bibliographystyle{plain}
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@ -5,87 +5,98 @@
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{
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\abstract{
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This paper analyses an inverting op-amp
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configuration, with the opamp and gain resistors using the FMMD
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configuration %, with the opamp and gain resistors
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using the FMMD
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methodology.
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%
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It has three base components, two resistors
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The circuit under analysis has five `base components', four resistors % two resistors programming gain, two programming a reference, or virtual ground voltage
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and one op-amp.
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%
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Two resistors are used as a current balance/virtual ground to program the gain
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of the amplifier and another pair to set the reference or virtual ground voltage.
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We consider the resistors setting the reference voltage as a functional group, a potential divider. %.$PD$.
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%where their function is to operate as a virtual ground voltage reference.
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The gain resistors work with the op-amp to determine the gain characteristics, and therefore the two gain resistors and the op-amp
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form a second functional group.% $GAMP$.
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%
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The base component failure modes
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are used to model each functional group %the amplifier from
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from a failure mode perspective.
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%
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We determine the failure symptoms from each of these {\fgs} and
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create {\dcs} to represent them.
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We can have a {\dc} represetnting the potential~divider and another representing the gain stage.
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The two resistors are used as a current balance/virtual ground to program the gain
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of the amplifier. We consider the two resistors as a functional group
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where their function is to operate as a current balance/virtual ground.
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We can now create a functional group representing the inverting amplifier,
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by bringing the {\dcs} %
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$PD$ and $GMAP$
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together to form a higher level functional group .
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%
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The base component error modes of the
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resistors are used to model the current balance/virtual ground from
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a failure mode perspective.
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%
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We determine the failure symptoms of the current balance/virtual ground and
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consider these as failure modes of a new derived component.
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We can now create a functional group representing the non-inverting amplifier,
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by bringing the failure modes from the current balance/virtual ground and
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the op-amp into a functional group.
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%
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This can be analysed and a derived component to represent the non inverting
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amplifier determined.
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This can be analysed and a derived component, %$INVAMP$
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created, to represent the failure mode behaviour of the inverting
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amplifier.
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}
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\section{Introduction}
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}
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{
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This chapter analyses an inverting op-amp
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configuration, with the opamp and gain resistors using the FMMD
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configuration %, with the opamp and gain resistors
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using the FMMD
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methodology.
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%
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It has three base components, two resistors
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and one op-amp.\section{Introduction}
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The two resistors are used as a current balance/virtual ground to program the gain
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of the amplifier. We consider the two resistors as a functional group
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where their function is to operate as a current balance/virtual ground.
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The circuit under analysis has five 'base components', four resistors % two resistors programming gain, two programming a reference, or virtual ground voltage
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and one op-amp.
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%
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Two resistors are used as a current balance/virtual ground to program the gain
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of the amplifier and another pair to set the reference or virtual ground voltage.
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We consider the resistors setting the reference voltage as a functional group, a potential divider $PD$.
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This chapter re-uses the $PD$ derived component from \ref{lab:nonivopamp}.
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%where their function is to operate as a virtual ground voltage reference.
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The gain resistors work with the op-amp to determine the gain characteristics, and therefore the two gain resistors and the op-amp
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form a second functional group $GAMP$.
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%
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The base component error modes of the
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resistors are used to model the current balance/virtual ground from
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a failure mode perspective.
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components are used to model each functional group %the amplifier from
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from a failure mode perspective.
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%
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We determine the failure symptoms of the current balance/virtual ground and
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consider these as failure modes of a new derived component.
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We determine the failure symptoms from each of these {\fgs} and
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create {\dcs} to represent them.
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We can create a functional group representing the non-inverting amplifier,
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by bringing the failure modes from the current balance/virtual ground and
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the op-amp into a functional group.
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We can now create a functional group representing the inverting amplifier,
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by bringing the {\dcs} $PD$ and $GMAP$ together to form a higher level functional group .
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%
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This can now be analysed and a derived component to represent the non inverting
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This can be analysed and a derived component, $INVAMP$ created, to represent the inverting
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amplifier determined.
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\section{Introduction: The non-inverting amplifier}
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}
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A standard non inverting op amp (from ``The Art of Electronics'' ~\cite{aoe}[pp.234]) is shown in figure \ref{fig:noninvamp}.
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A standard non inverting op amp (from ``The Art of Electronics'' ~\cite{aoe}[pp.178]) is shown in figure \ref{fig:invamp}.
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\begin{figure}[h]
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\centering
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\includegraphics[width=200pt,keepaspectratio=true]{./invopamp/noninv.png}
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\includegraphics[width=200pt,keepaspectratio=true]{./invopamp/inv.png}
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% noninv.jpg: 341x186 pixel, 72dpi, 12.03x6.56 cm, bb=0 0 341 186
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\caption{Standard non inverting amplifier configuration}
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\caption{inverting amplifier configuration with potential divider for reference/virtual ground}
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\label{fig:noninvamp}
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\end{figure}
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The function of the resistors in this circuit is to set the amplifier gain.
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They operate as a current balance/virtual ground and program the minus input on the op-amp
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to balance them against the positive input, giving the voltage gain ($G_v$)
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defined by $ G_v = 1 + \frac{R2}{R1} $ at the output.
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The voltage gain of this circuit ($G_v$)
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defined by $ G_v = -\frac{R4}{R3} $.
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\section{Potential Divider - OP-AMP Virtual ground reference}
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A functional group, is an ideally small in number collection of components,
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that interact to provide
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a function or task within a system.
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As the resistors work to provide a specific function, that of a current balance/virtual ground,
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As the resistors work to provide a specific function, that of a potential divider to program a given voltage,
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we can treat them as a functional group. This functional group has two members, $R1$ and $R2$.
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Using the EN298 specification for resistor failure ~\cite{en298}[App.A]
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we can assign failure modes of $OPEN$ and $SHORT$ to the resistors.
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@ -114,7 +125,7 @@ We can now represent a resistor in terms of its failure modes as a directed acyc
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}
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{
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}
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Thus $R1$ has failure modes $\{R1\_OPEN, R1\_SHORT\}$ and $R2$ has failure modes $\{R2\_OPEN, R2\_SHORT\}$.
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Thus for the potential~divider stage $R1$ has failure modes $\{R1\_OPEN, R1\_SHORT\}$ and $R2$ has failure modes $\{R2\_OPEN, R2\_SHORT\}$.
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%\clearpage
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@ -124,12 +135,12 @@ Thus $R1$ has failure modes $\{R1\_OPEN, R1\_SHORT\}$ and $R2$ has failure modes
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{
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Modelling this as a functional group, we can draw a simple closed curve
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to represent each failure mode, taken from the components R1 and R2,
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in the current balance/virtual ground, shown in figure \ref{fig:fg1}.
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in the potential divider, shown in figure \ref{fig:fg1}.
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\begin{figure}[h]
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\centering
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\includegraphics[width=200pt,keepaspectratio=true]{./invopamp/fg1.png}
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% fg1.jpg: 430x271 pixel, 72dpi, 15.17x9.56 cm, bb=0 0 430 271
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\caption{current balance/virtual ground `functional group' failure modes}
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\caption{potential divider failure modes}
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\label{fig:fg1}
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\end{figure}
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}
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@ -140,7 +151,7 @@ in the current balance/virtual ground, shown in figure \ref{fig:fg1}.
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{
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Modelling this as a functional group, we can draw this as a directed graph
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failure modes, taken from the components R1 and R2,
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in the current balance/virtual ground, shown in figure \ref{fig:fg1dag}.
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in the potential divider, shown in figure \ref{fig:fg1dag}.
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\begin{figure}
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\centering
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\begin{tikzpicture}[shorten >=1pt,->,draw=black!50, node distance=\layersep]
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@ -187,7 +198,7 @@ in the current balance/virtual ground, shown in figure \ref{fig:fg1dag}.
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}
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We can now look at each of these base component failure modes,
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and determine how they will affect the operation of the current balance/virtual ground.
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and determine how they will affect the operation of the potential divider.
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%Each failure mode scenario we look at will be given a test case number,
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%which is represented on the diagram, with an asterisk marking
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%which failure modes is modelling (see figure \ref{fig:fg1a}).
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@ -202,7 +213,7 @@ in table~\ref{pdfmea}.
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\centering
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\includegraphics[width=200pt,keepaspectratio=true]{./invopamp/fg1a.png}
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% fg1a.jpg: 430x271 pixel, 72dpi, 15.17x9.56 cm, bb=0 0 430 271
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\caption{current balance/virtual ground with test cases}
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\caption{potential divider with test cases}
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\label{fig:fg1a}
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\end{figure}
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}
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@ -216,10 +227,10 @@ For this example we can look at single failure modes only.
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For each failure mode in our {\fg} `potential~divider'
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we can assign a test case number (see table \ref{pdfmea}).
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Each test case is analysed to determine the `symptom'
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on the current balance/virtual grounds' operation. For instance
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on the potential diverders operation. For instance
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were the resistor $R_1$ to go open, the circuit would not be grounded and the
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voltage output from it would be the +ve supply rail.
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This would mean the symptom of the failed current balance/virtual ground, would be that it
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This would mean the symptom of the failed potential divider, would be that it
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gives an output high voltage reading. We can now consider the {\fg}
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as a component in its own right, and its symptoms as its failure modes.
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@ -301,13 +312,13 @@ have two symptoms, where the current balance/virtual ground will give an incorre
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or an incorrect high voltage (which we can term $HighPD$).
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We can represent the collection of these symptoms by drawing connecting lines between
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the test cases and naming them (see figure \ref{fig:fg1b}).
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\begin{figure}[h+]
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\centering
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\includegraphics[width=200pt,keepaspectratio=true]{./invopamp/fg1b.png}
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% fg1b.jpg: 430x271 pixel, 72dpi, 15.17x9.56 cm, bb=0 0 430 271
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\caption{Collection of current balance/virtual ground failure mode symptoms}
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\label{fig:fg1b}
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\end{figure}
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% \begin{figure}[h+]
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% \centering
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% \includegraphics[width=200pt,keepaspectratio=true]{./invopamp/fg1b.png}
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% % fg1b.jpg: 430x271 pixel, 72dpi, 15.17x9.56 cm, bb=0 0 430 271
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% \caption{Collection of current balance/virtual ground failure mode symptoms}
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% \label{fig:fg1b}
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% \end{figure}
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%\clearpage
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We can now make a `derived component' to represent this current balance/virtual ground.
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@ -317,13 +328,13 @@ We can use the symbol $\bowtie$ to represent taking the analysed
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{\fg} and creating from it, a {\dc}.
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%We could represent it algebraically thus: $ \bowtie(PotDiv) =
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\begin{figure}[h+]
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\centering
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\includegraphics[width=200pt,keepaspectratio=true]{./invopamp/dc1.png}
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% dc1.jpg: 430x619 pixel, 72dpi, 15.17x21.84 cm, bb=0 0 430 619
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\caption{From functional group to derived component}
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\label{fig:dc1}
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\end{figure}
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% \begin{figure}[h+]
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% \centering
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% \includegraphics[width=200pt,keepaspectratio=true]{./invopamp/dc1.png}
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% % dc1.jpg: 430x619 pixel, 72dpi, 15.17x21.84 cm, bb=0 0 430 619
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% \caption{From functional group to derived component}
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% \label{fig:dc1}
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% \end{figure}
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}
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{
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}
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@ -365,17 +376,61 @@ as a building block for other {\fgs} in the same way as we used the resistors $R
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\clearpage
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\section{Failure Mode Analysis of the OP-AMP}
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\section{Failure Mode Analysis of the OP-AMP Gain Section}
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Let use now consider the op-amp. According to
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FMD-91~\cite{fmd91}[3-116] an op amp may have the following failure modes:
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latchup(12.5\%), latchdown(6\%), nooperation(31.3\%), lowslewrate(50\%).
|
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The op-amp gain section use resistors $R4$ and $R3$ to determine the amount of negative gain.
|
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Each of the reistors have two failure modes $SHORT$ and $OPEN$.
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For our gain stage amplifier section, we have a {\fg} comprising
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the opamp, R3 and R4.
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\paragraph{Functional group context}
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We have to consider the context the amplifier is used it to determine its failure mode symptoms.
|
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If this were to be a instrumentaion amplifier, the low slew failure mode may not be a problem at all
|
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but could affect an audio amplifier by introducing low-pass filtering.
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TC2, TC1 and TC7, where there is no gain or ref voltage is output, could be very bad for an instrumentation amplifier
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because the oputput may be in a valid reading range for the application.
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|
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For the purpose of example we shall consider this amplifier to be an instumentation
|
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amplifier.
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\begin{table}[ht]
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\caption{Inverting Amplifier Gain Stage: Failure Mode Effects Analysis: Single Faults} % title of Table
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\centering % used for centering table
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\begin{tabular}{||l|c|c|l|l||}
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\hline \hline
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\textbf{Test} & \textbf{Amplifier} & \textbf{ } & \textbf{General} \\
|
||||
\textbf{Case} & \textbf{Effect} & \textbf{ } & \textbf{Symtom Description} \\
|
||||
% R & wire & res + & res - & description
|
||||
\hline
|
||||
\hline
|
||||
TC1: $R3_{OPEN}$ & Ref V. Output & & \\
|
||||
TC2: $R3_{SHORT}$ & High Gain & & OUT\_OF\_RANGE \\ \hline
|
||||
|
||||
TC3: $R4_{OPEN}$ & High Gain & & OUT\_OF\_RANGE \\
|
||||
TC4: $R4_{SHORT}$ & No Gain & & \\ \hline
|
||||
|
||||
TC5: $OPAMP$ LatchUP & High Output +Ve & & OUT\_OF\_RANGE \\
|
||||
TC6: $OPAMP$ LatchDown & Low Output -Ve & & OUT\_OF\_RANGE \\ \hline
|
||||
TC7: $OPAMP$ No Operation & Low Output -Ve & & OUT\_OF\_RANGE \\
|
||||
TC8: $OPAMP$ Low Slew & Low pass filter & & \\ \hline
|
||||
|
||||
|
||||
%TC7: $R_2$ OPEN & LOW & & LowPD \\ \hline
|
||||
\hline
|
||||
\end{tabular}
|
||||
\label{ampfmea}
|
||||
\end{table}
|
||||
|
||||
\ifthenelse {\boolean{pld}}
|
||||
{
|
||||
We can represent these failure modes on a diagram (see figure~\ref{fig:op1}).
|
||||
We can represent these failure modes of this {\fg} on a diagram (see figure~\ref{fig:op1}).
|
||||
\begin{figure}[h+]
|
||||
\centering
|
||||
\includegraphics[width=200pt,keepaspectratio=true]{./invopamp/op1.png}
|
||||
@ -389,7 +444,7 @@ We can represent these failure modes on a diagram (see figure~\ref{fig:op1}).
|
||||
|
||||
\ifthenelse {\boolean{dag}}
|
||||
{
|
||||
We can represent these failure modes on a DAG (see figure~\ref{fig:op1dag}).
|
||||
We can represent the failure modes of this {\fg} on a DAG (see figure~\ref{fig:op1dag}).
|
||||
\begin{figure}
|
||||
\centering
|
||||
\begin{tikzpicture}[shorten >=1pt,->,draw=black!50, node distance=\layersep]
|
||||
@ -407,11 +462,30 @@ We can represent these failure modes on a DAG (see figure~\ref{fig:op1dag}).
|
||||
\node[failure] (OPAMPNP) at (\layersep,-4) {noop};
|
||||
\node[failure] (OPAMPLS) at (\layersep,-6) {lowslew};
|
||||
|
||||
|
||||
|
||||
|
||||
\path (OPAMP) edge (OPAMPLU);
|
||||
\path (OPAMP) edge (OPAMPLD);
|
||||
\path (OPAMP) edge (OPAMPNP);
|
||||
\path (OPAMP) edge (OPAMPLS);
|
||||
|
||||
\node[component] (R3) at (0,-9) {$R3$};
|
||||
|
||||
\node[failure] (R3SHORT) at (\layersep,-8) {SHORT};
|
||||
\node[failure] (R3OPEN) at (\layersep,-10) {OPEN};
|
||||
|
||||
\path (R3) edge (R3SHORT);
|
||||
\path (R3) edge (R3OPEN);
|
||||
|
||||
\node[component] (R4) at (0,-14) {$R4$};
|
||||
|
||||
\node[failure] (R4SHORT) at (\layersep,-13) {SHORT};
|
||||
\node[failure] (R4OPEN) at (\layersep,-15) {OPEN};
|
||||
|
||||
\path (R4) edge (R4SHORT);
|
||||
\path (R4) edge (R4OPEN);
|
||||
|
||||
\end{tikzpicture}
|
||||
% End of code
|
||||
\caption{DAG representing failure modes of an Op-amp}
|
||||
@ -424,7 +498,7 @@ We can represent these failure modes on a DAG (see figure~\ref{fig:op1dag}).
|
||||
|
||||
%\clearpage
|
||||
|
||||
\section{Bringing the OP amp and the current balance/virtual ground together}
|
||||
\section{{\fg} forrmed from OP amp and the potential divider {\dcs}}
|
||||
|
||||
We can now consider bringing the OP amp and the current balance/virtual ground together to
|
||||
model the non inverting amplifier. We have the failure modes of the functional group for the current balance/virtual ground,
|
||||
@ -465,7 +539,6 @@ We can now crate a {\fg} for the non-inverting amplifier
|
||||
by bringing together the failure modes from \textbf{opamp} and \textbf{PD}.
|
||||
Each of these failure modes will be given a test case for analysis,
|
||||
and this is represented in table \ref{ampfmea}.
|
||||
|
||||
}
|
||||
{
|
||||
}
|
||||
@ -473,7 +546,7 @@ and this is represented in table \ref{ampfmea}.
|
||||
\clearpage
|
||||
|
||||
\begin{table}[ht]
|
||||
\caption{Non Inverting Amplifier: Failure Mode Effects Analysis: Single Faults} % title of Table
|
||||
\caption{Inverting Amplifier: Failure Mode Effects Analysis: Single Faults} % title of Table
|
||||
\centering % used for centering table
|
||||
\begin{tabular}{||l|c|c|l|l||}
|
||||
\hline \hline
|
||||
@ -482,12 +555,20 @@ and this is represented in table \ref{ampfmea}.
|
||||
% R & wire & res + & res - & description
|
||||
\hline
|
||||
\hline
|
||||
TC1: $OPAMP$ LatchUP & Output High & & AMPHigh \\
|
||||
TC2: $OPAMP$ LatchDown & Output Low : Low gain& & AMPLow \\ \hline
|
||||
TC3: $OPAMP$ No Operation & Output Low & & AMPLow \\
|
||||
TC4: $OPAMP$ Low Slew & Low pass filtering & & LowPass \\ \hline
|
||||
TC5: $PD$ LowPD & Output High & & AMPHigh \\ \hline
|
||||
TC6: $PD$ HighPD & Output Low : Low Gain& & AMPLow \\ \hline
|
||||
% TC1: $R3_{OPEN}$ & Output High & & AMPHigh \\
|
||||
% TC2: $R3_{SHORT}$ & Output Low : Low gain& & AMPLow \\ \hline
|
||||
%
|
||||
% TC3: $R4_{OPEN}$ LatchUP & Output High & & AMPHigh \\
|
||||
% TC4: $R4_{SHORT}$ LatchDown & Output Low : Low gain& & AMPLow \\ \hline
|
||||
%
|
||||
% TC5: $OPAMP$ LatchUP & Output High & & AMPHigh \\
|
||||
% TC6: $OPAMP$ LatchDown & Output Low : Low gain& & AMPLow \\ \hline
|
||||
% TC7: $OPAMP$ No Operation & Output Low & & AMPLow \\
|
||||
% TC8: $OPAMP$ Low Slew & Low pass filtering & & LowPass \\ \hline
|
||||
|
||||
TC9: $PD$ LowPD & Output High & & AMPHigh \\
|
||||
TC10: $PD$ HighPD & Output Low : Low Gain& & AMPLow \\ \hline
|
||||
|
||||
%TC7: $R_2$ OPEN & LOW & & LowPD \\ \hline
|
||||
\hline
|
||||
\end{tabular}
|
||||
@ -504,13 +585,13 @@ For this amplifier configuration we have three failure modes, $AMPHigh, AMPLow,
|
||||
\ifthenelse {\boolean{pld}}
|
||||
{
|
||||
We can now derive a `component' to represent this amplifier configuration (see figure ~\ref{fig:noninvampa}).
|
||||
\begin{figure}[h+]
|
||||
\centering
|
||||
\includegraphics[width=200pt,keepaspectratio=true]{./invopamp/noninvampa.png}
|
||||
% noninvampa.jpg: 436x720 pixel, 72dpi, 15.38x25.40 cm, bb=0 0 436 720
|
||||
\caption{Non Inverting Amplifier Derived Component}
|
||||
\label{fig:noninvampa}
|
||||
\end{figure}
|
||||
%\begin{figure}[h+]
|
||||
% \centering
|
||||
% \includegraphics[width=200pt,keepaspectratio=true]{./invopamp/noninvampa.png}
|
||||
% % noninvampa.jpg: 436x720 pixel, 72dpi, 15.38x25.40 cm, bb=0 0 436 720
|
||||
% \caption{Non Inverting Amplifier Derived Component}
|
||||
% \label{fig:noninvampa}
|
||||
%\end{figure}
|
||||
}
|
||||
{
|
||||
}
|
||||
|
||||
@ -1,5 +1,5 @@
|
||||
|
||||
|
||||
\label{lab:nonivopamp}
|
||||
|
||||
\ifthenelse {\boolean{paper}}
|
||||
{
|
||||
@ -723,6 +723,13 @@ to assist in building models for FTA, FMEA, FMECA and FMEDA failure mode analysi
|
||||
|
||||
|
||||
|
||||
\section{Deriving FTA, FMEA, FMECA and FMEDA models from the DAG}
|
||||
|
||||
The example here is very low level, or in other words is a very sysple sub-system.
|
||||
The FTA, FMEA, FMECA and FMEDA would normally be applied to a very large
|
||||
safety critical system (i.e. a car or a steam producing boiler plant).
|
||||
Th examples here show how the DAG provides a frame work for
|
||||
producing skeleton data forms for all these methodologies.
|
||||
|
||||
|
||||
\section{Extracting Fault Trees from the DAG}
|
||||
|
||||
@ -141,14 +141,14 @@
|
||||
|
||||
\chapter{FMMD functional~groups to \\derived component example : Non Inverting Op-AMP}
|
||||
\newboolean{dag}
|
||||
\setboolean{dag}{false} % boolvar=true or false
|
||||
\setboolean{dag}{true} % boolvar=true or false
|
||||
\newboolean{pld}
|
||||
\setboolean{pld}{true} % boolvar=true or false
|
||||
\typeout{ ---------------- non inv op amp}
|
||||
\input{noninvopamp/noninvopamp}
|
||||
|
||||
\chapter{FMMD functional~groups to \\derived component example : Inverting Op-AMP}
|
||||
\setboolean{dag}{false} % boolvar=true or false
|
||||
\setboolean{dag}{true} % boolvar=true or false
|
||||
\setboolean{pld}{true} % boolvar=true or false
|
||||
\typeout{ ---------------- non inv op amp}
|
||||
\input{invopamp/invopamp}
|
||||
|
||||
Loading…
Reference in New Issue
Block a user