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You can import signals from standard file formats such as ASCII comma- 
or tab-delimited files and LabVIEW measurement data files (

.lvm

). You 

also can import signals from simulated results of EDA tools such as SPICE 
simulators.

Complete the following steps to import a signal from a file.

1.

Right-click the Project View and select Load/Save Signals»Analog 
Signals»Load from ASCII from the shortcut menu.

2.

Click the browse button, shown at left, in the Step Setup dialog box, 
navigate to the 

SignalExpress\Examples\Tutorial

 directory, 

and double-click 

Step

 

Response.txt

. This step parses an ASCII file 

and displays the signals in the file.

In the File preview section, column 1 shows the time stamp data, and 
column 2 shows the actual voltage values of the signal.

3.

Click the Import Signals tab to display the available signals in the file.

4.

Place a checkmark in the Column 2 checkbox to import that signal, 
and remove the checkmark from the Column 1 checkbox.

The Step Setup dialog box displays a preview of the signal in the 
Imported Signal section.

5.

Select Column 1 from the Input X values pull-down menu to set the 
x-axis data of the waveform to the appropriate values.

6.

Open the Data View.

7.

Right-click the Column 2 output in the Project View and select 
Rename from the shortcut menu.

8.

Enter 

step

 

response

 and press the <Enter> key to rename the output.

9.

Drag the step response output of the Load from ASCII step to the 
lower graph in the Data View.

The filtered step signal resembles the rising edge of the step response 
output, as shown in Figure 4-2.