trigger delay in 5404

[labmaster]

I used PXI-5404, 10 MHz frequency source.

According to specification, 5404 has a delay of less than 250 usec in a frequency.

In my oscilloscope, the delay is around less than 500 nsec.

Does anyone who know how to calculate the delay depending on generating frequency?

For your reference, I am interested in the range of 1M~2MHz. 

labmaster. 

Message Edited by labmaster on 07-07-2009 12:34 PM

[jschwartz]

Hi labmaster,

From the help:

NI 5404 Analog Output

The following figure shows the timing relationships of the trigger input and waveform output. t_d1 is the pulse width on the trigger signal. t_d2 is the time delay from trigger to output on the SINE out.

The trigger delay is basically the time between the trigger being received and the SINE outputting. The 250 us spec would be the same for all frequencies. If you change frequencies, does your delay change?  How are you measuring the delay?

[labmaster]

The delay was measured by oscilloscope just after send the start trigger signal.

In my experiment, the delay is around 200 nsec (not usec) but depends on the generating frequency.

I know 250 usec is typical spec from NI specification sheet.

But, I believe there is a way to calculate the delay according to the frequency.

Please contact R&D department instead of me.

labmaster. 

[jaced]

Hi labmaster,

Can you please provide a detailed desription of your test set-up when you measure this delay. Most importantly the connections between the trigger/scope/and 5404.  Please be a specific as possible and a simple schematic would also be a big help if that is possible.

[labmaster]

Test PXI Moule: PXIe-1062Q

Function Generator: PXI-5404

DAQmx for Start trigger: PXIe-6124

Oscilloscope: Tek TDS-2014

The start trigger was generated from Counter signal, then routed (internally) to the function generator.

In the scope, the counter and 5404 signals were monitored under TRIGGER mode in terms of counter channel(ex. trigger source: CH1 and slope: rising mode).

Under this situation, I can see both signals then measure the starting delay of 5404.

For your reference, I feel some big trouble in similar things in estimating other AWG's (5416) delay.

http://forums.ni.com/ni/board/message?board.id=310&message.id=1641#M1641

I don't why the spec is not correct of NI signal generators.

I believe only R&D or developers of generators can solve these problems.

Feel free to ask me if you need some more information.

Message Edited by labmaster on 07-09-2009 02:59 PM

[lab_boy]

Hey Labmaster,

I tired trigger 5404 using another 5404 both generating at 20Mhz, the trigger delay was in around 250usec +- 2usec. Can you post the screenshot of the two signals.

Thanks

-lab

[jschwartz]

Hi Labmaster,

Here is the configuration that you could use to measure the delay:

[labmaster]

Both you are right. but I knew it.

I had better post my screen shot for your reference.

Labmaster.