Trigger Setup for Ring-Down Test in Datalogger

Support & Troubleshooting
1

This is a follow-up to the Trigger Setup for Ring-Down Test in Oscilloscope discussion. I’ve tried using the Datalogger instead, since the sampling rate of the Oscilloscope app isn’t high enough for capturing longer-duration ring-down measurements with sufficient resolution.

I basically followed the approach shared by @hanklong, using AM modulation on the driving signal to define the start of the ring-down. My device is driven in nonlinear region, so I need to sweep up the driving frequency and apply a -1V DC voltage as trigger signal instead of rect wave. However, it seems that the Datalogger trigger can only detect rising edges, not falling edges—so this method doesn’t appear to work as expected in the Datalogger.

Do you have any suggestions for how to configure the Datalogger to detect the moment the drive signal is turned off? Or any alternative ways to capture ring-down behavior effectively with Datalogger?

Thanks in advance for your help!
Xiangyu

2

Dear Xiangyu,

Would you please share the time duration and the sampling rate you need on your end? Thank you very much!

Best regards,
Heyang

3

at least 2M/s for ~0.5s.

4

Dear Xiangyu,

On Moku:Pro Oscilloscope single instrument mode, the OSC would be able to give you 7 seconds with 2 MSa/s if you choose the deep memory mode. However, the deep memory mode isn’t available in multi-instrument mode.

I think you might try outputting two signals simultaneously but with the opposite polarity. In this case, you would be able use one signal to modulate the waveform generator and the other for datalogger triggering.

The multi-instrument mode configuration would be:

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OutputA is a negative pulse signal, and OutputB is a trigger signal. The Arbitrary Waveform Generator ChA is

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And the AWG ChA is configured as burst modulation and triggered by InputA (ChB loop back).

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AWG ChA is the sine waveform modulation source, and ChB is actual trigger signal. Hope this helps.

Thanks,
Heyang