Pure Digital Simulations

PSpice can be used as a logic simulator as well as a mixed analog/digital simulator. We will now simulate a switch-tail counter. Wire the circuit as shown  

Instead of a node label, such as a bubble, having been placed on the ClOCh wire, the wire has been labeled. To label a wire, select Place and then Net Alias from the menus. A dialog box will appear, asking you for a label. Enter a name for the label and then place the label next to a wire. It is sometimes better to label a wire rather than add a bubble, because a bubble adds more clutter to a circuit drawing. 

When we run a digital simulation we must set up the Transient Analysis, as well as specify parameters for the digital simulation. We will first set up the Transient analysis. Select PSpice and then New Simulation Profile from the Capture menus, enter a name for the profile, and then click the Create button. By default the Time Domain (Transient) Analysis type is selected. Fill in the dialog box as shown to run the simulation for 20 ms  

Central Analysis include Files Libraries Stimulus Options Data Collection Probe Window i Analysis type  

Start saving data after. -Iransient options------ 

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PSpice can be used for pure digital simulations, pure analog simulations, or mixed analog/digital simulations. 

SCHEMATIC I Pur(3 Digital Simulation - PSpice A/D Lite - [exercise 8-2-SCHLMATIC I Pure Diqit BIHQjt... 

Seven simulated LC-UV/Vis DAS data matrices were constructed in MATLAB 5.0 (MathWorks Inc., Natick, MA). Each sample forms a 25 x 50 matrix. The simulated LC and spectral profiles are shown in Figure 12.3a and Figure 12.3b, respectively. Spectral and chromatographic profiles are constructed to have a complete overlap of the analyte profile by the interferents. Three of the samples represent pure standards of unit, twice-unit, and thrice-unit concentration. These standards are designated SI, S2, and S3, respectively. Three three-component mixtures of relative concentrations of interferent 1 analyte interferent 2 are 1 1.5 0.5, 2 0.5 2, and 2 2.5 1, and these are employed for all examples. These mixtures are designated Ml, M2, and M3, respectively. An additional two-component mixture, 2 2.5 0, is employed as an example for rank annihilation factor analysis. This sample is designated M4. In most applications, normally distributed random errors are added to each digitized channel of every matrix. These errors are chosen to have a mean of zero and a standard deviation of 0.14, which corresponds to 10% of the mean response of the middle standard. In the rank annihilation factor analysis (RAFA) examples, errors were chosen to simulate noise levels of 2.5 and 5% of the mean response of S2. In some PARAFAC examples, the noise level was chosen to be 30% of the mean response of the second standard. 

A simulated Mdssbauer spectrum can be calculated by digital computer for assumed values of H, e qQ, tj, 6, linear combinations. As we shall see in the next section this affects the intensities of the lines. Although the calculations are difficult, a combined magnetic-quadrupole interaction does potentially provide a large amount of data regarding the symmetry of the atomic environment. 

Figure 9.7 shows a relatively complete model of a plucked-string simulation system using digital filters. Output channels for pickup position and body radiation are provided separately. A solid-body electric guitar would have no direct radiation and only pickup output(s), while a purely acoustic guitar would have no pickup output, but possibly a family of directional filters to model body radiation in different directions. 

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