Transient Analysis
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Now we will test the transient state of the circuit. The transient analysis may
be performed after setting up of parameters for the analysis from Analysis
menu to pop up a window. Select Analysis/ Transient Analysis from the tree
view on the left side of the window.
1. Set the step value to .25ms and final time to 10ms. Select the option Waveform
from the drop down ‘Results’ to obtain the result in graphical format. If the
step value is increased then the number of iterations will also be increased.
2. When Transient analysis is executed, the interactive module extracts a SPICE netlist, stores it in a file called EDSPICE.CIR, and a group of commands are passed to the simulation engine (through a DDE link).
General Form of transient analysis is;
.TRAN TSTEP TSTOP >
3. TSTEP is the printing or plotting increment for line-printer output. TSTOP is the final time, and TSTART is the initial time. If TSTART is omitted, it is assumed to be zero. TMAX is the maximum step-size that SPICE uses; for default, the program chooses either TSTEP or (TSTOP-TSTART)/50.0, whichever is smaller.
4. After entering the values the information passed to the simulation engine is;
.TRAN .25mS 10mS
Note: The circuit file may be viewed by selecting File/ View EDSpice files/ Circuit (Spice Netlist)
5. Click on the RUN button to start the analysis. The simulation engine parses the netlist generated and when simulator engine has completed the analysis, the results of simulation are displayed in either graphical or textual form. The results are stored in the output files
RAWSPICE.RAW and EDSPICE.OUT. The waveform viewer pops up with the result as shown below.