RE: On-going work blog updates 1 - 3 Roadtesting the Rohde & Schwarz NGU401 SMU

neuromodulator — Mon, 05 Jul 2021 23:12:45 GMT

Hello Cosmin, what version of the firmware and sweeping tool are you using? When I try to perform the sweep it gets stuck in a "*STB?" infinite loop.

RE: On-going work blog updates 1 - 3 Roadtesting the Rohde & Schwarz NGU401 SMU

Gough Lui — Mon, 28 Jun 2021 07:53:12 GMT

The voltage selector fuse block system is pretty common amongst test equipment - even back in 2013, I experienced it with my Keithley 2110 RoadTest. Glad to see you figured it out.

As for the graphical view "oddity" - I suspect this could be a combination of two things:

The graphical view data may be sub-sampled by just taking one of the displayed values every x interval. This means you're basically "blind" to what is happening in-between so the plot itself will suffer from aliasing because it's basically sampling at a very low rate.
The phase-alignment between the measurement values which are used for display may not match the arbitrary waveform generation rate/speed exactly. A slow phase misalignment, given the display value has a minimum interval of 100ms or longer (depending on NPLC selection) means that you will see the voltage potentially slowly creep around.

I agree that it would be nice to plot it in a "filled" way, so plotting every Y-value for an X-bin of time. Having an adjustable timebase would be very good too, but sadly, it seems it is quite limited at this time.

You will probably discover (when using high-rate arb waveforms or mod input waveforms) that the metering on the front can stay seemingly "still" but the output of the SMU is very much producing a signal. You can easily see this by generating a waveform with an integer period synchronised with the ~100ms timebase. It is because of the speed of the SMU that having an oscilloscope monitoring or using FastLog data is necessary to actually know with more certainty what is actually happening.

- Gough

RE: On-going work blog updates 1 - 3 Roadtesting the Rohde & Schwarz NGU401 SMU

DAB — Sun, 20 Jun 2021 17:46:17 GMT

Very good initial post.

DAB

RE: On-going work blog updates 1 - 3 Roadtesting the Rohde & Schwarz NGU401 SMU

geralds — Sun, 20 Jun 2021 12:54:11 GMT

Hi [mention:20de3d39ce8d4f81acb3a7a4693cbeac:e9ed411860ed4f2ba0265705b8793d05] ,

Thank you for your first impression.

I'm very curious about your detailed review.

Best Regards

Gerald

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