oscilloscope for digital pulse - Page 1
Forum section: electronics / beginners

author: 5282
author_rank: Regular Contributor
timestamp: March 24, 2018, 05:21:58 pm
content: helloi want oscilloscope for high speed digital clock like 100mhz.i just want oscilloscope to know the pulse phase degree(time delay between pulse) come out from fpgaso what i should search for oscilloscope( sample rat or analogue bandwidth) is important for me ??.i don't have enough money("my money can buy 1gsa/s oscilloscope").

author: Benta
author_rank: Super Contributor
timestamp: March 24, 2018, 06:30:58 pm
content: QuoteWell, that limits your options.If you just need to make certain you have a quadrature signal, a fast XOR gate with output rectification and smoothing could do the job.

author: cstratton
author_rank: Regular Contributor
timestamp: March 24, 2018, 06:34:35 pm
content: Making sure your logic is correct, that you've properly used the FPGA toolchain's timing constraint mechanism, and that you've matched the board delays would go a long way towards achieving your goal.

author: BravoV
author_rank: Super Contributor
timestamp: March 24, 2018, 06:48:37 pm
content: Repeatedly begging on multiple threads throughout the forum won't help you.

author: Simon
author_rank: Unknown
timestamp: March 24, 2018, 07:05:21 pm
content: We had all of this a little over a year ago......

author: 5282
author_rank: Regular Contributor
timestamp: March 24, 2018, 07:25:13 pm
content: 1gsa/s oscilloscope can help me?i want to measure 2.5ns delay between pulse.

author: txescientist
author_rank: Regular Contributor
timestamp: March 24, 2018, 07:36:16 pm
content: Well, it is difficult. See the attachment

author: tautech
author_rank: Super Contributor
timestamp: March 24, 2018, 10:04:47 pm
content: Quote from: 5282 on March 24, 2018, 07:25:13 pmProbably the best bang for buck for your needs is the 2 ch 200MHz SDS1202X-E.They've been in the marketplace for nearly 1 year and proving to be very popular.All the documentation so you can research it is here:https://www.siglenteu.com/digital-oscilloscopes/sds1000x-e-series-super-phosphor-oscilloscopes/There's a thread here on EEVblog too that's easy to find.You can find your closest supplier here:https://www.siglenteu.com/how-to-buy/

author: abraxa
author_rank: Frequent Contributor
timestamp: March 24, 2018, 11:05:15 pm
content: Quote from: tautech on March 24, 2018, 10:04:47 pmI know you're trying to be helpful but capturing a 100 MHz square wave with a 200 MHz analog bandwidth isn't going to be fun. Unless I misunderstood the thread starter and he/she really means milli Hertz, that is.

author: tautech
author_rank: Super Contributor
timestamp: March 24, 2018, 11:21:00 pm
content: Quote from: abraxa on March 24, 2018, 11:05:15 pmFrom the OP:QuoteI'd take that to mean 100 MHz as I know of no 'high speed digital clock' that runs at milli hertz.So many post here using the wrong units and we get sick/lazy about correcting them, but we should.When there's enough info in a post so that's clear what is meant we can then make a recommendation.Probing technique and the 2 signal sources will determine the accuracy of a '2.5ns delay between pulse' but all things being equal (probe connection and same signal source) the DSO mentioned is capable of such measurement.As with many things that start to push the envelope of an instrument, operator skill needs to be up to the task.If you can recommend a better instrument at a better price point, well please do.

author: Zero999
author_rank: Super Contributor
timestamp: March 24, 2018, 11:41:58 pm
content: An oscilloscope is no good for this anyway. A timer counter is the correct tool for the job. No doubt it's possible to build one with an FPGA, but don't ask me. I have no experience with them. They're magic, as far as I'm concerned.

author: vk6zgo
author_rank: Super Contributor
timestamp: March 25, 2018, 01:05:16 am
content: If the Oscilloscope is comparing the phase/time delay between two nominally identical waveforms, there is a fair bet that the distortion to each waveform due to limited 'scope bandwidth will also be identical, so you can measure the time difference between the same point on the two waveforms.Maybe, this is not good enough for absolute measurements, but once they are done, it may well be good enough for checking continual compliance.

author: 5282
author_rank: Regular Contributor
timestamp: March 25, 2018, 05:08:57 pm
content: thank to all for helping me.

author: Mechatrommer
author_rank: Super Contributor
timestamp: March 25, 2018, 07:08:04 pm
content: Quote from: abraxa on March 24, 2018, 11:05:15 pmif money is the limiting factor. any 1GSps 100-200MHz scope capable of 2ns per division or smaller should be able to show some usefull info about it. with proper probing (termination technique) and the user brain power, this can be a good practice at debugging with limited capability tool. knowledge is power, albeit will not be a nice square (sine) but its better than breaking a bank.

author: 5282
author_rank: Regular Contributor
timestamp: March 26, 2018, 11:15:31 am
content: thank you but i'm very Puzzled between.buy low cost 100mhz oscilloscope and hack it to 200mhz.are there any different between hacked oscilloscope and original oscilloscope??.