Tektronix P7313SMA, Technical Reference

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Performance Veri fi cation
Deskew Channel 7 and 8 by doing the following:
7. Check that Ch 7 is set to negative slope and Ch 8 is set to positive slope.
8. Verify/clear all deskew values for Ch 7 and Ch 8 in both the TDR menu and the vertical menu.
9. Turn off the display for Ch 7 and Ch 8 so that only Ch 4 is shown on screen.
10. Set the horizontal scale to 10 ps/div, and the vertical scale to 50 mV/div.
11. Adjust Ch 4 to position the step at 0 V, and then enter –125 mV offset to position the step as shown. (See Figure 31.)
Save this waveform to a reference.
Figure 31: Deskew the TDR steps
12. Remove Ch 7 from the Ch 4 input and connect Ch 8 to the Ch 4 input.
13. Press the Ch 4 button to display Channel 4.
14. Enter 125 mV offset to position the step as shown. (See Figure 31.)
15. From the TDR menu, adjust the deskew on Ch 8 to align the edges with the reference value from step 11.
16. Use the oscilloscope measurement capability to display rise time. Increase the stability of the pulse edge measurement
by using averaging, if available. Rise time is measured from the 10% and 90% amplitude points on the waveform.
Record the rise time as
t
s.
44 P7313SMA Technical Reference