I just received the new Logic MSO and am now looking through its functionality. The analog channels are just great, meaning I can now get rid of my bench scope.
One thing I noticed is that it is apparently no longer possible to trigger on protocol results. Did I miss something, or is it intentionally left out?
@nebel Sorry about that! You are correct in the Logic MSO currently does not have Trigger View functionality implemented.
Let me check in with the team here to see if we plan to include this in an update.
+1 on protocol triggering.
Note that in the analyzer view you can look at the data in the data table. As soon as you hover over a value in that table a little arrow appears on the right side. When you click on that arrow, your signal view will move to that time. This often is already good enough for me.
Don’t get rid of your bench scope too quickly.
The analog channels are indeed nice and I do use them from time to time but I still like to take my bench scope to do some more detailed measurements.
The unit has a fixed measurement range, good enough for most 3.3V signals but on small signals (e.g. measurement on a crystal oscillator) or for detailed measurements (I just had to do some rise/fall time check on a 1 Mbit CAN bus) I only fully trust my bench scope.
Rob
According to Logic MSO — Portable USB Mixed-Signal Oscilloscope | Saleae | Saleae the full scale range adjusts from +/- 10 mV to 60 V.
It’s my understanding that the Logic MSO has a programmable gain amplifier which can be adjusted based on the vertical scale settings, as long as you don’t set it to ‘fixed range’ to disable this feature. So, I believe the 9-bit ADC model has ~40uV/bit resolution and the 12-bit has ~5 uV/bit – much better analog specs than the Logic 8/16 Pro, which did have a fixed range and lower bandwidth.
Note: if you want maximum measurement performance, you may want to use the fixed scaling setting, and then carefully calibrate your channel probes to tune the frequency response. If you want to be really precise, then you should also wait until after the scope has fully warmed up and in a stable room temperature environment (i.e., 30 min warmup at 23 ± 5 °C).
It’s my understanding that the Logic MSO has a programmable gain amplifier
Oops, I missed that one. I was thinking of the Logic Pro, not the MSO.
The specs of this one are as good as, if not better, than my bench oscilloscope.
Rob
Since the probes are fixed to a 10x attenuation, this means up to 600 V, right? In fact, one can adjust the vertical scale to -500 V to +500 V.
I believe so. I’m pretty sure the analog specs are for the core hardware and analog front end (AFE), not including the external attenuation (or amplification) of any attached probes. So, I think the included probes will limit your minimum range to 10X the specs, unless you use a 1X probe / cable (which could then affect your maximum signal frequency, depending on the probe).
So, with the included 10X probes:
I believe the 9-bit ADC model has ~400uV/bit resolution and the 12-bit has ~50 uV/bit (due to the 10X attenuation of the probe into the scope).
Also, be aware that as you change your vertical scale, the scope might be automatically adjusting gain/offset settings inside, and these different settings are not perfectly balanced across all possible ranges/resolutions (no scope can do this perfectly – it is just how it works, but some are better tuned/balanced than others).
That is why you may want to use the fixed scaling feature to decouple your view/zoom from the AFE setup and then calibrate your probe at an exact/known setting that doesn’t subtly change as you modify your view. Not really needed for simple measurements, but it could explain some variations in more precise measurements (or if you just want to get more accurate results).
Thanks @BitBob for jumping in on how the analog front end of Logic MSO works!
@nebel, you’re right, protocol triggering is still missing from Logic MSO. We have some issues with the triggering system that are blocked by some ongoing lower level work, but I do plan to get back to that. Unfortunately I can’t promise an ETA. (We have 2 software developers including myself, and we’ve both been pulled into supporting firmware and manufacturing test changes related to ongoing supply chain issues. I hope to get back to active Logic 2 software development at the start of next month)