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How to avoid jitter in analog output(square wave) generation

Hi all,
Iam working with PCI-6723 32 channels analog output,iam generating a square wave,sampling at 100ks/s.
ican able to generate upto 10kHz square wave.The wave form appears clean when it is below 1000Hz if i crossed 5KHz to 7KHz, iam getting jitter in the output square wave form,i have experimented with the digital filter but still the jitter is persisting,
since iam using 12 channels for such similar generations so i have fixed the sampling rate.100Ks/s.
kindly suggest me how to avoid this jitter in high frequency generation.

OS::WINDOWS 2000
HARDWARE PCI-6723.
I/O :SCB 68
NIDAQ:7.3
LABVIEW 7.1

kindly find the attached file.

Thanks and Regards
RAJESH
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Rajesh,
I'd like to help you with your jitter problem. Could you please include some additional information. By jitter, does it just look like noise on the square wave? If not, what does this jitter look like? Do you get the same jitter when you use output on only one channel, or is it only when you output on all of your 12 channels? Finally, how are you looking at the signal to see the jitter?
-Alan A.
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Hi ALAN,
Thanks for your reply, well the square appears to be overlapped ie one ON/OFF period another waveform tries to overlap, actually i planned to take a snapshot of my oscilloscope (tetronix) but since its not advanced one ,i have attached the file kindly look into it,you can observe the at some higher frequencies there is lot of difference between rise time and fall time.

Thanks and Regards
rajesh
alan actually iam decorating my front pannel do u have any sample layouts for coloring ,buttons kindy forward me .
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Rajesh,
I don't think you are seeing jitter, atleast I didn't notice any by looking at your picture. One thing I'd like to point out is that you are updating at 100K samples/sec. That is one sample every 10 microseconds. That is exactly the rise and fall time that is shown on your picture. You can not achieve a faster rise or fall time than 10 microseconds if you are updating at 100K samples/sec.
As for decorating your front panel, I would suggest going to Help>>Find Examples in LabVIEW and take a look at the shipping examples.
-Alan A.
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