ch07.1.htm

来自「介绍asci设计的一本书」· HTM 代码 · 共 2,844 行 · 第 1/5 页

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(7.1)</P>
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The linear superposition of the branch currents gives the voltage at node <SPAN CLASS="EquationVariables">
i </SPAN>
as  </P>
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d<SPAN CLASS="EquationVariables">
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<SPAN CLASS="EquationVariables">
R</SPAN>
<SUB CLASS="SubscriptVariable">
ki</SUB>
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C</SPAN>
<SUB CLASS="SubscriptVariable">
k</SUB>
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(7.2)</P>
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where <SPAN CLASS="EquationVariables">
R</SPAN>
<SUB CLASS="SubscriptVariable">
ki</SUB>
 is the resistance of the path to <SPAN CLASS="EquationVariables">
V</SPAN>
<SUB CLASS="Subscript">
0</SUB>
 (ground in this case) shared by node <SPAN CLASS="EquationVariables">
k</SPAN>
 and node <SPAN CLASS="EquationVariables">
i</SPAN>
. So, for example, <SPAN CLASS="EquationVariables">
R</SPAN>
<SUB CLASS="Subscript">
24</SUB>
 = <SPAN CLASS="EquationVariables">
R</SPAN>
<SUB CLASS="Subscript">
1</SUB>
, <SPAN CLASS="EquationVariables">
R</SPAN>
<SUB CLASS="Subscript">
22</SUB>
 = <SPAN CLASS="EquationVariables">
R</SPAN>
<SUB CLASS="Subscript">
1</SUB>
+<SPAN CLASS="EquationVariables">
R</SPAN>
<SUB CLASS="Subscript">
2 </SUB>
, and <SPAN CLASS="EquationVariables">
R</SPAN>
<SUB CLASS="Subscript">
31</SUB>
 = <SPAN CLASS="EquationVariables">
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<SUB CLASS="Subscript">
1</SUB>
. </P>
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Unfortunately, Eq.&nbsp;<A HREF="CH07.1.htm#13241" CLASS="XRef">
7.2</A>
 is a complicated set of coupled equations that we cannot easily solve. We know the node voltages have different values at each point in time, but, since the waveforms are similar, let us assume the slopes (the time derivatives) of the waveforms are related to each other. Suppose we express the slope of node voltage <SPAN CLASS="EquationVariables">
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 as a constant, <SPAN CLASS="EquationVariables">
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, times the slope of <SPAN CLASS="EquationVariables">
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,  </P>
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Consider the following measure of the error, <SPAN CLASS="EquationVariables">
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