Hi, my name is Cory, and I work at Agilent Technologies in the R&D lab.
Customers have told us that when they are using our X-series analyzers, they have difficulty
setting up the gate when they are using very narrow pulses.
I am here to show you a new feature that we have added to make it easier to set up the
gate function with narrow pulses.
I have got a PXA signal analyzer here and a PSG signal generator.
Let us get started.
When you are making gated measurements, you wanna set the "gate start time", which
is represented by the gate delay, to a number that is larger than this "min-fast" value
here.
This blue line here, with the label min-fast, shows you the time below which you do not
want to set the gate delay.
If you try to set the gate delay lower than that, you will have to use a much lower sweep
time to overcome transience in the system.
You really have to use min-fast as the minimum value for your gate delay time.
In this case, we have set the gate start time to longer than min-fast and because the duty
cycle of the pulse is about 50%, we have no trouble setting the gate length represented
by the "gate stop" value here.
That the "gate start" and the "gate stop" points fall well within the pulse.
That is for a pulse like this, where we have about 50% duty cycle.
This is a 50 µs pulse width.
Now, if I change the pulse width to 5 µs, now you can see we are going to have difficulty
setting the gate start and the gate stop times on that pulse, so that we are pretty sure
that the gate is only open when the pulse is high.
Because the min-fast time is here, we have to use this first pulse after min-fast, and
if we change the gate view sweep time, so that we can see more of the pulse, it is not
very long before the pulse that we are trying to set the gate on just goes completely off
the screen.
To solve this problem, a new parameter called "gate view start time", has been added.
The gate view start time is the time at the left side of the screen.
What we can do now is set the gate view start time to near what the min-fast time is, and
then we will have plenty of range to set our gate view sweep time.
If I turn on a marker, and I move the marker to the min-fast line, I can see that min-fast
is at about 328 µs.
Let us set the gate view start time to be about 320 µs.
When we do that, now I can make the gate view sweep time smaller and smaller.
In fact, let us move it down to about 75 µs, and now you can see here is the min-fast line,
here is the first pulse after min-fast, and again, I am not going to have any trouble
setting the gate delay and the gate length, so that they are nicely on the pulse.
So when I turn on the gate, I get a solid line at the top of the screen, which is what
you want.
So that is how gate view start time makes it easier to make measurements on narrow pulses
in the PXA signal analyzer.
The PXA is the industry's highest performance signal analyzer, but this feature is also
available on other members of the X-series.
For more information, visit our website at this URL: www.agilent.com/find/pxa
Thank you for watching.