EEVblog Electronics Community Forum
Products => Test Equipment => Topic started by: Harjit on December 09, 2018, 02:08:35 am
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About to purchase a SDS1104X-E.
Was wondering if there was a similar scope but with a 10bit ADC?
Plan to use it for brushless motor and optical sensor stuff for robots.
Thanks,
Harjit
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There are, but they cost a fair bit more, e.g. R&S RTB2000
So you need 10 bits of dynamic resolution? e.g. 1024 steps for a measurement, or you want to see the noise on a large dc component?
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I might be wrong but IIRC some of the Hameg oscilloscopes have more than 8 bit ADCs. The downside is that those oscilloscopes have a 640x480 display.
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The RTB2004 does, but is not cheap.
Owon XDS3000 have a cheaper higher bit scope.
Higher bit scope are more the domain of USB scopes than benchtop scopes.
https://www.youtube.com/watch?v=ByUiOk00K0U (https://www.youtube.com/watch?v=ByUiOk00K0U)
https://www.youtube.com/watch?v=-F4H-zC_i0s (https://www.youtube.com/watch?v=-F4H-zC_i0s)
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The RTB2004 does, but is not cheap.
Owon XDS3000 have a cheaper higher bit scope.
But they don't have the features Zynq provides.
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Plan to use it for brushless motor and optical sensor stuff for robots.
Why would you need 10 bit scope for that?
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But they don't have the features Zynq provides.
pascal_sweden, is that you?! Long time no see! :P
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About to purchase a SDS1104X-E.
Was wondering if there was a similar scope but with a 10bit ADC?
Plan to use it for brushless motor and optical sensor stuff for robots.
Thanks,
Harjit
10bit ADC but with SDS1104X-E features
Was wondering if there was a similar scope but with a 10bit ADC?
Features, which in particular ?
Dual ADC's ?
Memory depth ?
Decode ?
500uV/div full BW sensitivity ?
1 Mpts FFT ?
History, Sequence, Search ?
Webserver ?
Bode plots ?
Non reflective glass TFT display ?
Pass/Fail ?
400V inputs ?
LAN, dual USB ?
MSO option ?
AWG option ?
WiFi option ?
etc. etc.
Good luck with your hunt at this price point.
Oh, and BTW, the Eres 0.5 - 3 bit mode might give you the additional resolution you seek.
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Want to be able to see noise on a large signal - basically, a decent dynamic range.
From a memory depth point of view, anything more than 1M points per channel is fine.
Can you elaborate on the Eres 0.5 - 3 bit feature? Is it decimating the signal to get more bits? If so, it might be enough. I haven't started using it.
Thanks for the tip on the Owon. I saw Dave's video reviews and he seemed quite down on it - it was weird because he seemed upset from the get go. Anyway, he talked about a lot of user interface, thermal design and usage issues. Didn't seem there were that many functional issues - once it was configured but there were configuration (user interface)issues. From looking at the datasheet for the ADC, it can do 12bits at 1GS/s and 14 bits at 105MS/s. The closest in price seems to be the XDS3104AE. Initially, I couldn't tell how the sampling rate changed with number of channels but found it in the manual. In 8 bit mode @ 4 Ch it is 250MS/s. In 12 bit mode @ 4 Ch it is 125MS/s. In 14 bit mode @ 4 Ch it is 100MS/s. I'm quoting 4 Ch because that is the important case for me.
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Want to be able to see noise on a large signal - basically, a decent dynamic range.
OK if you can't use AC coupling then you need a good offset range.
The SDS1004X-E datasheet lists the offset capabilities in the Vertical specs
https://www.siglentamerica.com/wp-content/uploads/dlm_uploads/2018/05/SDS1000X-E_DataSheet_DS0101E-E03B.pdf (https://www.siglentamerica.com/wp-content/uploads/dlm_uploads/2018/05/SDS1000X-E_DataSheet_DS0101E-E03B.pdf)
From a memory depth point of view, anything more than 1M points per channel is fine.
Nothing at all demanding then. :)
Can you elaborate on the Eres 0.5 - 3 bit feature? Is it decimating the signal to get more bits? If so, it might be enough. I haven't started using it.
In this excellent review, Eres is covered in some detail:
https://www.eevblog.com/forum/testgear/siglent-sds1104x-e-in-depth-review/ (https://www.eevblog.com/forum/testgear/siglent-sds1104x-e-in-depth-review/)
Download this from the first post that includes the Eres chapter:
SDS1104X-E Review 26-50.pdf
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Be careful with Eres (or other high resolution modes). You'll need to have some amount of white noise in the signal to make oversampling work. And the ADCs also need to be linear. All in all Eres is nice to make a signal look cleaner but if you want extra resolution then you need the extra bits. There is a good reason there are >8bit oscilloscopes!
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Want to be able to see noise on a large signal - basically, a decent dynamic range.
From a memory depth point of view, anything more than 1M points per channel is fine.
Can you elaborate on the Eres 0.5 - 3 bit feature? Is it decimating the signal to get more bits? If so, it might be enough. I haven't started using it.
Thanks for the tip on the Owon. I saw Dave's video reviews and he seemed quite down on it - it was weird because he seemed upset from the get go. Anyway, he talked about a lot of user interface, thermal design and usage issues. Didn't seem there were that many functional issues - once it was configured but there were configuration (user interface)issues. From looking at the datasheet for the ADC, it can do 12bits at 1GS/s and 14 bits at 105MS/s. The closest in price seems to be the XDS3104AE. Initially, I couldn't tell how the sampling rate changed with number of channels but found it in the manual. In 8 bit mode @ 4 Ch it is 250MS/s. In 12 bit mode @ 4 Ch it is 125MS/s. In 14 bit mode @ 4 Ch it is 100MS/s. I'm quoting 4 Ch because that is the important case for me.
In most case, you don't need 10-bit scope to see small noise on large DC components. You can turn up the gain on the input, let the trace go off screen and use the DC_Offset to bring trace back to screen. Siglent scope can do 1mV/div on top of 1V no problem. Old Tektronix analog scopes were very good at measuring this type thing.
The trick is to make sure the scope won't go into phase reversal or have terrible overdrive recovery. The Siglent's overdrive recovery is not great, but if you just need to see noise on a DC signal, it is no problem. If you want to see 1mV noise on large AC signal, you will need to get a Keysight or LeCory one (only certain models, Tektronix should be OK, but I never used any of their digital ones), which has good overdrive recovery capability.
A 10-bit or higher resolution scope will NOT help you, if
1. they do not have digital phosphor type display (most recent ones have it)
2. they have lousy analog front end. In my opinion, majority so-called high resolution data acquisition is short on analog front end design, so you won't have true 12-bit or 16-bit performance.