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2.7 Time-Domain Analysis of Nonlinear Dynamic Circuits 113
In[14]:= TransientPlot[Vpulse[t], {t, 0., 10^−5},
PlotRange −> {−1, 3}]
3
2.5
2
1.5
1
Vpulse[t]
0.5
-0.5
-6
2. 10
-6
4. 10
-6
6. 10
-6
8. 10
0.00001 t
-1
Out[14]= Graphics
Then, we call
NDAESolve to simulate the transient behavior of the differential amplifier for t ∈ Μs. The
NonlinearMethod option allows for choosing between different algorithms for solving systems of
nonlinear algebraic equations numerically. By default, Mathematica’s numerical solver FindRoot is
applied, whereas in this example we want to make use of another implementation of Newton’s
method called NewtonIteration.
In[15]:= transient = NDAESolve[diffAmpMNA /. V1 −> Vpulse[t],
{t, 0., 10^−5}, NonlinearMethod −> NewtonIteration];
Now, we use TransientPlot to plot the waveforms of the input and output voltages V$1 and V$5.
In[16]:= TransientPlot[transient, {V$1[t], V$5[t]},
{t, 0., 10^−5}]
12
10
8
V$1[t]
6
4
V$5[t]
2
-6
2. 10
-6
4. 10
-6
6. 10
-6
8. 10
0.00001 t
Out[16]= Graphics
DC-Transfer Analysis
Next, we shall compute the DC-transfer characteristic V out V in ⩵ V$5[V1] of the differential
amplifier circuit as the input voltage is swept from V to V. Therefore, we first set up the
static circuit equations by calling CircuitEquations with the option setting AnalysisMode −> DC.