Products > Test Equipment

Desktop DSO for hardware and firmware development of MCU systems

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nctnico:

--- Quote from: Wilson__ on September 13, 2024, 05:42:29 pm ---
--- Quote from: 2N3055 on September 13, 2024, 04:49:20 pm ---To cut the story short, SDS2000X+ ( with full BW) is going to be more than fast enough to look into SPI.

Even to achieve full BW of SDS2000X+ your biggest problem will be probing and will be most limiting factor.

--- End quote ---
Sorry, coming from thru-hole age.  How to probe QFN chip SPI signals?  'Test version' PCB with test point?

--- End quote ---
Solder thin (enamel) wires to the best possible location. Typically you'll want to use series resistors on SPI interfaces to dampen reflections so these are good points. Otherwise you'll need to solder really thin (enamel) wires to QFN pads and bring them to a 2.54mm header or something like that. Not impossible to do but still a nuisance.

2N3055:

--- Quote from: Wilson__ on September 13, 2024, 05:42:29 pm ---
--- Quote from: 2N3055 on September 13, 2024, 04:49:20 pm ---To cut the story short, SDS2000X+ ( with full BW) is going to be more than fast enough to look into SPI.

Even to achieve full BW of SDS2000X+ your biggest problem will be probing and will be most limiting factor.

--- End quote ---
Sorry, coming from thru-hole age.  How to probe QFN chip SPI signals?  'Test version' PCB with test point?

Googled says, https://www.edn.com/oscilloscope-probe-accessories-its-the-little-things-that-matter/

--- End quote ---

One of the often forgotten things is "design for test". Provide test points for critical signals. Not only on prototype.
If you change layout from prototype to production, how do you know you didn't influence things?
You can solder in short extensions to probe tip (making sure you have good ground), use spring ground or similar.

Really high speed active probes are mostly solder in..

For some probing, you can use 10x LoZ probe together with 50Ω inputs..

Trick is to minimise capacity (to minimise circuit load) and inductance as seen by probe.. And to stay with high enough DC resistance to minimize DC load. Art of compromises.

Ideally you could use an active probe, but we if are talking about budget options, maybe something homemade or by one of the members here that occasionally spin some prototypes..

tautech:

--- Quote from: Wilson__ on September 13, 2024, 04:36:31 pm ---
--- Quote from: KungFuJosh on September 12, 2024, 05:09:12 pm ---If you have the budget to go higher than the SDS2000X Plus, then compare it with the SDS2000X HD. Either one would be a great scope for your needs

--- End quote ---
Many thanks for info.  My use is design verification.  Use DSO to inspect signal lines to confirm that there is no abnormal glitch nor invalid signal. Are below correct?

1. The MCU and external chips works at 10MHz SPI clock.  Likely these silicon are tens of nm node and will not response to glitch that is many times narrower than the normal 10MHz wanted-signal.

2. SDS2000X Plus is 1 or 2GSa/s in 4 or 2 channel mode.  So, I got 100 to 200 dots for the 10MHz signal.  Spec. also says 1ns peak detection.  Presumably, refers to best case signal at full swing voltage (3.3 volts).  Presumably, the scope will detect lower-voltage glitch at, says, 1 volt, of a few ns long. 

3. SDS2000X Plus will do the job, right?  If the scope does not see any glitch, the glitch energy, (voltage multipy time) should be too weak to cause the chip to response, right?

--- End quote ---
The modern DSO is pretty powerful at finding stuff you might not even think is present.....it's all about using the features available to see that you might have a problem then applying the toolset to capture them.



This ^^^ screenshot is a good example where some Persistence shows it's present then we can narrow in and seen if it's a one off or repetitive.
In this post I did a similar exercise with the older SDS1104X-E which gives some idea of using a few of the scopes features:
https://www.eevblog.com/forum/testgear/siglent-sds1204x-e-released-for-domestic-markets-in-china/msg1370717/#msg1370717

Wilson__:

--- Quote from: tautech on September 13, 2024, 08:59:14 pm ---
--- Quote from: Wilson__ on September 13, 2024, 04:36:31 pm ---
--- Quote from: KungFuJosh on September 12, 2024, 05:09:12 pm ---If you have the budget to go higher than the SDS2000X Plus, then compare it with the SDS2000X HD. Either one would be a great scope for your needs

--- End quote ---
Many thanks for info.  My use is design verification.  Use DSO to inspect signal lines to confirm that there is no abnormal glitch nor invalid signal. Are below correct?

1. The MCU and external chips works at 10MHz SPI clock.  Likely these silicon are tens of nm node and will not response to glitch that is many times narrower than the normal 10MHz wanted-signal.

2. SDS2000X Plus is 1 or 2GSa/s in 4 or 2 channel mode.  So, I got 100 to 200 dots for the 10MHz signal.  Spec. also says 1ns peak detection.  Presumably, refers to best case signal at full swing voltage (3.3 volts).  Presumably, the scope will detect lower-voltage glitch at, says, 1 volt, of a few ns long. 

3. SDS2000X Plus will do the job, right?  If the scope does not see any glitch, the glitch energy, (voltage multipy time) should be too weak to cause the chip to response, right?

--- End quote ---
The modern DSO is pretty powerful at finding stuff you might not even think is present.....it's all about using the features available to see that you might have a problem then applying the toolset to capture them.



This ^^^ screenshot is a good example where some Persistence shows it's present then we can narrow in and seen if it's a one off or repetitive.
In this post I did a similar exercise with the older SDS1104X-E which gives some idea of using a few of the scopes features:
https://www.eevblog.com/forum/testgear/siglent-sds1204x-e-released-for-domestic-markets-in-china/msg1370717/#msg1370717

--- End quote ---

Comparing SDS1104X-E and SDS2104X-Plus.  Does the cheaper unit have same toos/function (trigger, search, measure) for the purpose of design verification, to hunt for abnormal signals in 10MHz SPI signal between MCU and external chips?

Is there more differences than what I found so far from scanning manual:

500MSa/s   vs   1000MSa/s in 4 channels mode (MISO, MOSI, Clock, nChipSelect), 500M is 50 samples per 10MHz signal pulse.  Enough to see abnormal glitch, runt, overshoot, undershoot???

7 Mpts/CH  vs  100Mpts, 7M captures 140,000 pulses at 50 samples per pulse. 

No histogram, still has StdDev to qualtify signal jitter.

7 inches and non-touch screen.   Needs a few more human seconds to use knobs to active a function, right?

tautech:

--- Quote from: Wilson__ on September 16, 2024, 10:00:58 am ---
--- Quote from: tautech on September 13, 2024, 08:59:14 pm ---
--- Quote from: Wilson__ on September 13, 2024, 04:36:31 pm ---
--- Quote from: KungFuJosh on September 12, 2024, 05:09:12 pm ---If you have the budget to go higher than the SDS2000X Plus, then compare it with the SDS2000X HD. Either one would be a great scope for your needs

--- End quote ---
Many thanks for info.  My use is design verification.  Use DSO to inspect signal lines to confirm that there is no abnormal glitch nor invalid signal. Are below correct?

1. The MCU and external chips works at 10MHz SPI clock.  Likely these silicon are tens of nm node and will not response to glitch that is many times narrower than the normal 10MHz wanted-signal.

2. SDS2000X Plus is 1 or 2GSa/s in 4 or 2 channel mode.  So, I got 100 to 200 dots for the 10MHz signal.  Spec. also says 1ns peak detection.  Presumably, refers to best case signal at full swing voltage (3.3 volts).  Presumably, the scope will detect lower-voltage glitch at, says, 1 volt, of a few ns long. 

3. SDS2000X Plus will do the job, right?  If the scope does not see any glitch, the glitch energy, (voltage multipy time) should be too weak to cause the chip to response, right?

--- End quote ---
The modern DSO is pretty powerful at finding stuff you might not even think is present.....it's all about using the features available to see that you might have a problem then applying the toolset to capture them.



This ^^^ screenshot is a good example where some Persistence shows it's present then we can narrow in and seen if it's a one off or repetitive.
In this post I did a similar exercise with the older SDS1104X-E which gives some idea of using a few of the scopes features:
https://www.eevblog.com/forum/testgear/siglent-sds1204x-e-released-for-domestic-markets-in-china/msg1370717/#msg1370717

--- End quote ---

Comparing SDS1104X-E and SDS2104X-Plus.  Does the cheaper unit have same toos/function (trigger, search, measure) for the purpose of design verification, to hunt for abnormal signals in 10MHz SPI signal between MCU and external chips?

Is there more differences than what I found so far from scanning manual:

500MSa/s   vs   1000MSa/s in 4 channels mode (MISO, MOSI, Clock, nChipSelect), 500M is 50 samples per 10MHz signal pulse.  Enough to see abnormal glitch, runt, overshoot, undershoot???

7 Mpts/CH  vs  100Mpts, 7M captures 140,000 pulses at 50 samples per pulse. 

No histogram, still has StdDev to qualtify signal jitter.

7 inches and non-touch screen.   Needs a few more human seconds to use knobs to active a function, right?

--- End quote ---
TBH, today if wanting a lower cost solution and happy with a 7" display, SDS814X HD is where it's at.

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