Author Topic: USB logic analyzer - what's the current "favorite" for ~150$? Hantek 4032L?  (Read 16403 times)

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Offline toliTopic starter

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Hi All,

I was looking into possibly extending the capabilities of my gear when it comes to a logic analyzer. Since this will eventually be used mainly for hobby use, I'd like to keep it at ~150$ or less.

My "must haves" include 16 channels, samples rate of >100MSPS, and adjustable threshold level (some of the things I use don't have "standard" logic levels), a couple Mpoints of memory are also very much appreciated.
If I'm being picky, I would actually like to get >200MSPS sample rate, more than 16 channels, and it would make my life easier for some use cases to be able to use external clock for sampling.
I will use it mostly as a general purpose device for SPI/I2C/RS232/similar simple interfaces I might use in projects.
However, having a more capable device will allow me to use it for reading data out of test chips I'm working on as part of my Ph.D. studies. While I do have tools to do this at the university, having a small device at home that can allow me to work on this whenever I want is a great advantage.

One candidate I'm currently looking at is the Hantek 4032L. Its almost within budget, it has 32channel, 64Mpoints per channel, 400MSPS, adjustable voltage levels, and supports (in latest fw) external clock for sampling. From what I read the software is ok at best, but it seems to be well supported (and improving over time) by PulseView which is a great point in its favor (I could perhaps implement additional decoding here instead of MATLAB like I'm doing today).

After this long intro, about time I get to the questions :)
1 - I've seen limited number of user reviews of the 4032L, and the few I've seen are from a few years ago. Are there any users of this device here on the forum that can share their experience with the device/provide real world opinion about it? Is it any good? Are there any major bugs/limitations? Anything else I should be aware of before getting one?
2 - Are there other suggested devices that are considered better/will fit my needs better?

Thank you.
« Last Edit: July 04, 2018, 08:13:27 pm by toli »
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Offline maginnovision

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If you don't need the 32 channels I'd say get something with better support. If you do want to get the 4032 you need to use sigrok or write your own program for anything other than basic decoding. I'm torn on sigrok, it's missing alot of things I need but the 4032 developer is doing what he can with the driver. The factory software is sufficient for individual lines or parallel busses. The advanced triggers are the reason I still use it. The software is pretty much unusable in 4K though. Overall, I'd say it's good but first and third party software have their issues. If you have any specific questions I can try to answer them.
 
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Offline TK

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You can check the Zeroplus LAP-C 16032... it has only 16 channels, 100MSa/s and 32K per channel but it supports over 100 protocols included for free.  Price in the US is around $130
 
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Offline 1anX

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I got the DSLogic Plus and it does what I want!        http://www.dreamsourcelab.com/order.html
Check the thread on this forum.
« Last Edit: July 05, 2018, 10:21:11 pm by 1anX »
 
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Offline toliTopic starter

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Thank you all for the comments.

maginnovision, assuming I will be using sigrok, what are the issues you are seeing with this combo? From what I read the current version supports external clock, and has most of the features implemented already, or am I wrong? Where do you feel it falls short compared to other options?
One more thing has to do with operating it on an external clock. Any idea how fast this clock can actually be? I see this mode is much slower for most devices, but I can't see a note of this mode in the spec for the Hantek.

TK, 32KB is just not enough for me unfortunately. There are some cases where I need a few MB. 100Msa/s are also the bare minimum I can get away with for some applications. So if I can get stronger HW for the price I will definitely go that way.

1anX, from what I read about it, the SW is based on sigrok too, and therefore has many similarities. If that is the case, will it actually be any better than using sigrok on the 4032L? The reason I'm asking is because when comparing the spec, its a stronger unit (the Hantek). More channels, higher sample rate, and more memory. For instance, I now have a project where the output is 12bit parallel bus (actually 32, but I can get away with 12 at a time) + 50MHz sample clock. For this the DSlogic is running at the edge of what it can do, although it does seem to support this. For this I has to implement the readout using a Cypress FX3 EVB. While it wasn't too bad, if I could simply hook it up to a LA and dump a few MB's per channel into a csv file - it would have been even faster and easier.
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Offline maginnovision

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maginnovision, assuming I will be using sigrok, what are the issues you are seeing with this combo? From what I read the current version supports external clock, and has most of the features implemented already, or am I wrong? Where do you feel it falls short compared to other options?
One more thing has to do with operating it on an external clock. Any idea how fast this clock can actually be? I see this mode is much slower for most devices, but I can't see a note of this mode in the spec for the Hantek.

Sigrok doesn't support advanced triggers, it's high or low for one line only. If that isn't the case then for me it crashes 100% of the time otherwise. That includes if I forget to deselect one line as trigger before selecting another, I don't need to start an acquisition. The external clock is most useful only if you can match your clock rate to the sample rate pulldown selection. Although potentially useful as well for capturing a lot of serial data. Again it may just be me but it crashes when using decoders and trying to scan through the data before they're fully decoded. With 64M samples that can take a while though. It doesn't save the setup on restart/crash, so if you have line A13 following A15 once it restarts it resorts back to numerical order. If you start sigrok before the LA is connnected and powered on you again lose your entire setup including labels and added decoders. The one saving grace there is typically when you re-add the decoders the lines are still set but you still lose your labels. Even without decoders if I try to scan through data during an acquisition or shortly after it crashes. It's alot of little things that make it hard for me personally to recommend it but when their software also has an equal number of issues... I end up keeping both installed. Neither of them can take full advantage of the hardware.

The good news though is that sigrok probably will improve. The hantek software never will.
 

Offline toliTopic starter

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Thank you for the detailed response, highly appreciated.
The problems you describe sound like a major PITA, and if this is indeed the current situation I'd like to avoid it.

Quote
The external clock is most useful only if you can match your clock rate to the sample rate pulldown selection.
I think this is only true if you want a time stamp on the data. For my usage of external clock I don't care about time stamp, only about being able to maximize the sampled data. Oversampling (with high speed internal clock) is a waste of memory if I can instead sample only when valid data is present :)

I was under the impression sigrok now works well with the Hantek device, and will just keep on improving. However, what you are describing is barely usable (if I understand correctly), and there is obviously no guarantee this will improve in the foreseeable future  :-\

Are these issues shared among all users of this device, or is this something that you only observe on one machine/operating system/other combo? Just trying to understand if this is something that can circumvented somehow.
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Offline abraxa

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Quote
If that isn't the case then for me it crashes 100% of the time otherwise. That includes if I forget to deselect one line as trigger before selecting another, I don't need to start an acquisition. The external clock is most useful only if you can match your clock rate to the sample rate pulldown selection. Although potentially useful as well for capturing a lot of serial data. Again it may just be me but it crashes when using decoders and trying to scan through the data before they're fully decoded. With 64M samples that can take a while though. It doesn't save the setup on restart/crash, so if you have line A13 following A15 once it restarts it resorts back to numerical order. If you start sigrok before the LA is connnected and powered on you again lose your entire setup including labels and added decoders. The one saving grace there is typically when you re-add the decoders the lines are still set but you still lose your labels. Even without decoders if I try to scan through data during an acquisition or shortly after it crashes.

While I appreciate your honest criticism, I would like to point out that no problems will ever be fixed that the team doesn't know about. PulseView works just fine for a whole lot of people, and when something doesn't work for you, it's worth creating a bug report in bugzilla.
 

Offline toliTopic starter

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abraxa, can you share your input about the combo of 4032L with sigrok?
Getting more info from as many users as I can will be very helpful in making the right decision here.

I understand sigrok is the work of people from the community, many of which are members of this forum (and perhaps it the opportunity to thank them for the work they are doing  :clap:). As such, I understand it will improve over time which is a great benefit of such software. I just want to understand where its at right now, and what is expected in the near future so I'll know if this combo will be useful for me now or I should looks for another piece of HW (be it with sigrok or other SW) :)
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Online coppice

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While I appreciate your honest criticism, I would like to point out that no problems will ever be fixed that the team doesn't know about. PulseView works just fine for a whole lot of people, and when something doesn't work for you, it's worth creating a bug report in bugzilla.
I think Sigrok suffers a lot from people giving it a try, finding issues, and moving on without taking any further action. That's death for an open source project, while rational feedback is its life blood.
 

Offline Doctorandus_P

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If you have any curiousity in te direction of Sigrok I would recommend to start with a "8ch 24M" box from Ali / Ebay. The price of this box is so low (About EUR 5) that there is no reason not to buy it, even though it does not live up to your full specs.
I've captured and decoded some low-speed USB signals (1.5mbit/s) with this box and it  is enough to give you an Idea of what Sigrok can do.

A general CY7C68013A development board goes upto 16 channels in Sigrok, but does not have any input protection. You could add a buffer yourself with the any logic level you like.
You may even state that the input protection is included in the pricetag. Just buy 10 of these EUR3.05 boards, and exchange them if you did something stupid and blew the inputs.

For more capable hardware you may want to have a look at what is supported by Sigrok:
https://sigrok.org/wiki/Supported_hardware
 

Offline toliTopic starter

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Thank you for the comment.
That is exactly what I did, the 4032L is in the supported devices list and seems like the most capable device there :)
Only problem is that "supported" is a wide term, so I'd like to get more real world comments from users of this combo.
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Offline 17_29bis

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One more vote for DSLogic Plus, it was around 130USD, supports up to 400Mhz for 4 channels (see the screenshots for choosing different speed), up to 4G (RLE compression) memory size (256Mb RAM onboard), adjustable threshold level, possibility to use external clock (did not try), long list of decoders (I am familiar with 5 or 6 different decoders), ability to stack them (useful for work with low speed USB devices, fox example), ability to write your own encoders (python), cursor measurements, buffering and streaming data acquisition modes  (USB2 speed limit). It has external trigger input and output (I had a problem with one of them, dont remember which but I still was able to chain Analog Discovery (it has very advanced triggering system) and DSLogic Plus through external trigger connection).

Bad things: the GUI (sigrok fork/ or "being inspired by sigrok") DSView v0.9.7.1 (2 or so years old) was the last public release (but I still prefer ti very much to the original sigrok GUI). The support forum is almost dead, I had a difficult time to setup an advanced trigger but found a work around through the usage of external trigger.

Full specification of the device (less than I paid  :'( ):
https://www.ebay.com/itm/New-DSLogic-Plus-DSLogic-Pro-16CH-100MHz-USB-Logic-Analyzer-/253587496006

Device review:
https://hackaday.com/2017/08/24/dslogic-plus-teardown-and-review/









« Last Edit: July 05, 2018, 08:21:27 pm by 17_29bis »
 

Offline toliTopic starter

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Thank you all for the help so far.
Following the input from members in this thread, as well as more reading over the web since I've started this topic, seems like the current state is the following:
DSlogic Pro - doesn't meet my desired requirements, but does meet my minimum requirements.
HW wise it has adjustable threshold and sufficient memory which are meeting my desired numbers. The number of channels and sample rate and BW are marginal for some of my needs. The external clock seems to be at constant 3.3V level which isn't what I need and I'll have to "fix" it externally with a level shifter.
SW wise it seems like many people aren't too happy with it. This is at least what I read on different forums online, including here, and looking at reviews on websites selling this device.
So overall it will do most of what I need, but for some of the more demanding applications I will have to look elsewhere. The price of <100USD is obviously a nice point in its favor, as well as the slick design of the unit.

However, before I'm settling for something that doesn't really meet my desired needs, I'd like to give that 4032L one more chance. The HW benefits of extra memory (which I don't need, the DSlogic has enough memory for me), and more importantly higher sample rate and BW, more channels, and if I understand correctly adjustable threshold on external clocks - are all very tempting. The fact its almost double the price is something I can live with, its worth the extra cost if it'll save me the drive to the lab at the university by letting me work on my test boards from home.
There is still an open issue about the HW, namely the maximum clock frequency for CLKA/CLKB inputs. I'm still not able to find a straight answer to that question, is it the 150MHz claimed BW, or lower? I have no idea at the moment. I've sent Hantek an email today, lets see if they ever get back to me :)
The biggest issue I see so far is the SW. I've read maginnovision's comments here, and they are definitely not positive. Despite this, I'm still trying to get input from other users of the 4032L/sigrok combo, to try and get a better feeling of how usable/unusable it really is.

Thank you all again.
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Offline abraxa

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I apologize in advance for hijacking this thread for my comments but I just can't stay quiet.

Quote
One more vote for DSLogic Plus, it was around 130USD

Of which exactly $0 went towards sigrok, by the way. Not even a single line of usable code because they not only didn't want to work with us, they actively sabotaged any effort of upstreaming anything.

Quote
long list of decoders (I am familiar with 5 or 6 different decoders), ability to stack them (useful for work with low speed USB devices, fox example), ability to write your own encoders (python), cursor measurements, buffering and streaming data acquisition modes  (USB2 speed limit)

...which are all features that the sigrok team (and community, in the case of protocol decoders) is responsible for - including the Cypress FX2 firmware that the DSLogic uses.

Quote
Bad things: the GUI (sigrok fork/ or "being inspired by sigrok") DSView v0.9.7.1 (2 or so years old) was the last public release (but I still prefer ti very much to the original sigrok GUI).

Seriously? You applaud them for taking our work, making the UI look "fancy", making money off of it of which we see exactly zero, adding some minor features here and there and then crap on us for having neither the man power nor the time to do the same? Hint: none of us gets paid and we support a wide range of devices - not just one. Making things work for one device is easy, making stuff work for *all* devices is not.

That is exactly what I did, the 4032L is in the supported devices list and seems like the most capable device there :)
Only problem is that "supported" is a wide term, so I'd like to get more real world comments from users of this combo.

That's in flux, as is to be expected. From the driver perspective, the functionality that you require is implemented. If you look at the driver source, you can see that the threshold levels are adjustable and the external clock can be used. I don't know the device well enough to say whether the threshold levels also apply to the external clocks but I'd assume so. If you want to be sure, you can mail the person who implemented support for external clocks in the driver: https://sigrok.org/gitweb/?p=libsigrok.git;a=commit;h=f49065c6682b720800e05e8e2821a193b251d65a

Regarding the external clock rate: the hardware and driver have no way of finding out what the clock rate is or if it's even stable. That's why you as a user must provide the clock rate using the drop-down menu if you want to have accurate timing information. The fact that there are only pre-defined values can be an issue here I reckon, but that'll be fixed in the future so that you will be able to enter arbitrary values.
« Last Edit: July 05, 2018, 09:34:11 pm by abraxa »
 
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Offline toliTopic starter

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Thank you for this comment. Regarding external clock, I have no need to know exactly what it is in the software time stamps, as long as I can export all the data to CSV and process it in MATLAB. The question there was about the clock frequency the HW can support - I can't find a straight answer in the device datasheet about the maximum clock frequency I can use in this mode, this will probably be limited by the speed of the IO buffers and comparator they use. I'd guess 150MHz BW as they claim should support 150MHz clock, but one can never be sure unless its in the datasheet or someone else can test it :)
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Offline maginnovision

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Thank you for this comment. Regarding external clock, I have no need to know exactly what it is in the software time stamps, as long as I can export all the data to CSV and process it in MATLAB. The question there was about the clock frequency the HW can support - I can't find a straight answer in the device datasheet about the maximum clock frequency I can use in this mode, this will probably be limited by the speed of the IO buffers and comparator they use. I'd guess 150MHz BW as they claim should support 150MHz clock, but one can never be sure unless its in the datasheet or someone else can test it :)

I would expect 150mhz to be the limit. If you just need to export data I suspect using the sigrok CLI should work for you in which case I'd say go for it.
 

Offline 17_29bis

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Of which exactly $0 went towards sigrok, by the way. Not even a single line of usable code because they not only didn't want to work with us, they actively sabotaged any effort of upstreaming anything.
...which are all features that the sigrok team (and community, in the case of protocol decoders) is responsible for - including the Cypress FX2 firmware that the DSLogic uses.
Seriously? You applaud them for taking our work, making the UI look "fancy", making money off of it of which we see exactly zero, adding some minor features here and there and then crap on us for having neither the man power nor the time to do the same? Hint: none of us gets paid and we support a wide range of devices - not just one. Making things work for one device is easy, making stuff work for *all* devices is not.

All this is very strange. I am the END USER who found DSLogic on the web, checked the specs and bought the device before I  even heard the name sigrok. "0$ dollars, you applaud" - what are you talking about?  And what is even more what am I supposed to do now? Throw it way, ask for refund, start drinking heavily due to the guilt? if you have a problem with dev. of DSLogic then deal with them in civilized way withing drawing the people who has nothing to do with that into it.
 

Offline 1anX

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DSLogic Plus which is what I purchased and it seems is under your consideration has just released an updated version of their software (based originally on Sigrok as others have pointed out). The software I have been using was V0.98 and I have just downloaded the update V0.99 this week and will install sometime soon.

I like their software, (DSLogic) and have zero problems in using it. My previous experience with Sigrok software and Win 10 and Linux was frustrating to say the least so by using DSLogic's program I was up and running immediately.

Download latest V0.99 here >   http://www.dreamsourcelab.com/download.html
« Last Edit: July 06, 2018, 03:45:01 am by 1anX »
 

Offline SMB784

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So I bought the $60 Chinese knockoff of the DSLogic basic, soldered in a $3 sdram chip onto the unpopulated SDRAM slot on the board (creating the equivalent of a $100 DSLogic Plus knockoff), and installed sigrok pulseview on my Raspberry Pi 3B+. The specs on the DSLogic Plus are 400 MS/s sample rate, 256MByte capture memory, and claimed 50 MHz bandwidth, though I suspect that it is much higher, maybe as much as 150 MHz judging by the sample rate

When you build it from the source according to the website instructions, pulseview works flawlessly with this device. Bang for buck, the aforementioned setup beats the pants off of the Hantek, and can handle almost anything you throw at it.

A couple years back i was an extreme sigrok skeptic, but they have worked hard and have released enough updates that I am really very pleased with sigrok, it's great software and you can't beat free
« Last Edit: July 05, 2018, 10:45:14 pm by SMB784 »
 

Offline toliTopic starter

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SMB784, this device is not meeting my desired spec as I've described above. The 50MHz limitation isn't a function of sample rate for most devices, its about the speed of the comparator and timing constraints of the digital logic. Therefore its impossible to look at the maximum sample rate and understand what the maximum frequency it can sample will be. As I mentioned above, this model (the pro) is my plan B (or maybe C), since it isn't what I really want in a LA. Bang for bug isn't the parameter I'm looking for, I'm looking for something that can technically do what I want, which out of the devices I've seen so far only the Hantek can.
If I come to the conclusion I can't use the Hantek due to software limitation I'll get the DSlogic Pro, and live with the fact it can only due the more basic things I need. But so far it seems the Hantek isn't "dead" yet. Especially considering the SW will keep improving.

I'm still on the fence here though, the two users who have experience with this combo (abraxa and maginnovision) agreeing that it can do what I want, but if I understand correctly there are bugs at the moment that might make it a not so pleasant experience :)
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Offline SMB784

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SMB784, this device is not meeting my desired spec as I've described above. The 50MHz limitation isn't a function of sample rate for most devices, its about the speed of the comparator and timing constraints of the digital logic. Therefore its impossible to look at the maximum sample rate and understand what the maximum frequency it can sample will be. As I mentioned above, this model (the pro) is my plan B (or maybe C), since it isn't what I really want in a LA. Bang for bug isn't the parameter I'm looking for, I'm looking for something that can technically do what I want, which out of the devices I've seen so far only the Hantek can.
If I come to the conclusion I can't use the Hantek due to software limitation I'll get the DSlogic Pro, and live with the fact it can only due the more basic things I need. But so far it seems the Hantek isn't "dead" yet. Especially considering the SW will keep improving.

I'm still on the fence here though, the two users who have experience with this combo (abraxa and maginnovision) agreeing that it can do what I want, but if I understand correctly there are bugs at the moment that might make it a not so pleasant experience :)

The reason why I brought up the DSLogic pro is that I'm not convinced that it's limited to 50MHz. It has a Spartan 6 in it, and I don't see a reason why the comparator in the would be limited to the input Crystal frequency. These things are rated to much higher frequencies, and in order to generate a sampling clock of 400MS/s they must be capable of at least that frequency.  My bet is that the actual input bandwidth is higher than 50MHz, as the Nyquist frequency for a 400MHz sample clock is around 160MHz

Offline toliTopic starter

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Looks like you are right and it really does support higher BW. I've been watching videos from the OpenTechLab channel on youtube over the last few weeks, so today I've finally watched his review of the DSlogic Plus:
https://www.youtube.com/watch?time_continue=3&v=xZ5wKYnCNcs
Seems like the use of the coaxial leads and the way they implement the input stage really does give a significant advantage when it comes to high speed sampling.it really is very impressive that this small device can get to 200MHz input clock.

So this does make the option of getting the DSlogic plus (with the coaxial leads, no reason for me to keep twisting wires together if I don't have to, for 30$ its worth it :)) significantly more appealing than it was until this point. The number of boxes it doesn't tick in my desired spec just got smaller.

I'll try sending DreamSourceLab an email and ask them about the external clock mode. I'd like to understand if there are any other limitation to it and if the threshold voltage is indeed constant for 3.3V CMOS levels. If the threshold level is fixed this will be somewhat of a PITA for me to do this myself every time.
SMB784, do you have any way of feeding a clock into this pin and testing one (or both) of these parameters (maximum frequency it can run at, and threshold level adjustment support)?
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Offline SMB784

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I'll try sending DreamSourceLab an email and ask them about the external clock mode. I'd like to understand if there are any other limitation to it and if the threshold voltage is indeed constant for 3.3V CMOS levels. If the threshold level is fixed this will be somewhat of a PITA for me to do this myself every time.

Judging by their spec sheet on their website tells me that the threshold is continuously variable between 0 and 5V, though I don't know how to do that yet.

SMB784, do you have any way of feeding a clock into this pin and testing one (or both) of these parameters (maximum frequency it can run at, and threshold level adjustment support)?

I will see if I can get my hands on a >100 MHz square wave generator.  If not, then I dont think I can find something that I could use to test this :-/

Offline toliTopic starter

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Question is if this 0-5V range also holds for the CLK input vs just the 16 data channels. I think I've seen somewhere a mention that the CLK input is at 3.3V constant, but I can't seem to recall where it was.

BTW, you don't actually need >100MHz square wave to test these parameters. The threshold can be checked at low speed quite easily (and if I'm honest that's the more interesting parameter for me at the moment). For the maximum frequency test a sin wave will suffice. At these frequencies the rise time will limit square waves and they will look more like a sine anyway unless you take extra good care of the test setup. I've actually used sin wave input at 100MHz to the Cypress FX3 IC as a sampling clock because of a similar limitation, and its works like a charm with no issues at all (just add VDD/2 DC offset obviously :)).
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