FPGA oscilloscope circuit - Page 1
Forum section: electronics / general

author: yalect
author_rank: Regular Contributor
timestamp: September 24, 2018, 09:58:41 pm
content: Hi,I would like to ask you if I can buy FPGA chip to build fast oscilloscope circuit.Thank you

author: ataradov
author_rank: Super Contributor
timestamp: September 24, 2018, 10:15:10 pm
content: Sure. A lot of commercial scopes are built around Xilinx Zynq, which are readily available from Digi-Key.

author: yalect
author_rank: Regular Contributor
timestamp: September 24, 2018, 11:34:40 pm
content: Sorry, I mean I am looking for simple FPGA oscilloscope circuit which I can buy FPGA chip and program it to build fast oscilloscope.Thanks

author: ataradov
author_rank: Super Contributor
timestamp: September 24, 2018, 11:37:24 pm
content: "Simple" and "fast" are not compatible. Forget about it. To build a scope, you need to have a better scope already.Also parts separately in single quantities will cost more than a real scope. And FPGA is not the most expensive component, the ADC is.

author: NorthGuy
author_rank: Super Contributor
timestamp: September 24, 2018, 11:40:02 pm
content: Quote from: yalect on September 24, 2018, 11:34:40 pmAbsolutely. It won't be cheap though:https://www.xilinx.com/products/silicon-devices/soc/rfsoc.html

author: nctnico
author_rank: Super Contributor
timestamp: September 25, 2018, 12:03:42 am
content: Red Pitaya en Digilent AD2 come to mind.

author: Mechatrommer
author_rank: Super Contributor
timestamp: September 25, 2018, 12:08:36 am
content: Quote from: ataradov on September 24, 2018, 11:37:24 pmfast is a relative term. we can say 100MSa/s is fast compared to 1MSa/s... to OP, here is your cheap and fast solution...https://www.ebay.com.my/itm/DSO168-Handheld-mini-pocket-digital-oscilloscope-20M-bandwidth-100M-sampling/123119301045?hash=item1caa7b71b5:g:8JIAAOSwIIha76hMno need to build anything...

author: Morgan127
author_rank: Contributor
timestamp: September 25, 2018, 06:02:37 am
content: I use thisInternal Logic Analyzerand displays the data as analog. This works up to approx 300-MSps I guess.The screen update rate looks like any other oscilloscope. Using this you can use almost any Xilinx-fpga/boards.It is also free to download and use.

author: NorthGuy
author_rank: Super Contributor
timestamp: September 25, 2018, 01:12:38 pm
content: Quote from: Morgan127 on September 25, 2018, 06:02:37 amIs that with built-in 1MS/s ADC?

author: Morgan127
author_rank: Contributor
timestamp: September 25, 2018, 01:27:13 pm
content: QuoteNo that is with external ADC. With the internal XADC you get 1 MSps max.

author: NorthGuy
author_rank: Super Contributor
timestamp: September 25, 2018, 01:54:54 pm
content: Quote from: Morgan127 on September 25, 2018, 01:27:13 pmWhat external ADC do you use it with?

author: PCB.Wiz
author_rank: Super Contributor
timestamp: September 25, 2018, 08:53:52 pm
content: Quote from: yalect on September 24, 2018, 11:34:40 pmDo you mean a pre-built module when you say "simple FPGA oscilloscope circuit" ?You can use almost any FPGA out there, as a basis for an oscilloscope.The FPGA is only a small portion of the puzzle.You also need fast transport to some PC host, and a fast ADC.Those items are harder to define, and design with, than a FPGA.eg you might select a FT60x USB-3 bridge device, as the fast PC host link, then you need to bridge between that and your ADC, using the FPGATo find a module, you could drop into Digikeys search engine forEvaluation Boards - Analog to Digital Converters (ADCs)and pick some MSPS that meets your 'fast', then sort by price.Or, you could browse Module companies, likehttps://www.trenz-electronic.de/en/Company/Projects/4-channel-Flash-ADC/No price there, but that says " sampling rates up to 5 GHz." so might meet your 'fast' ?and from abovehttps://shop.trenz-electronic.de/en/Red-Pitaya/https://shop.trenz-electronic.de/en/27069-Analog-Discovery-2?c=76orhttps://www.scopefun.com/orhttps://hackaday.com/2017/11/18/ds212-oscilloscope-review-open-source-and-great-for-hacking/orhttps://www.makerfabs.com/fabs/index.php?route=product/product&product_id=524

author: rhb
author_rank: Super Contributor
timestamp: September 25, 2018, 10:40:23 pm
content: The cheap and easy solution is to buy an Instek GDS-2072E and hack it. It's everything you need. I've set up a Zynq/Cyclone dev platform to implement FOSS FW for COTS DSOs. There's a thread on that. At the moment I'm rewiring my workspace. I bought my 2072E (now at 300 MHz) as a test bed with the good luck to get it for $244 from Amazon. However, even at the regular price, it's a good platform. I think Siglent also sell a Zynq based DSO.ALL the low cost DSOs are FPGA based so anyone of those will work. The Zynq is particularly attractive because the boot is public stated.If you want "fast" as in 2-3 GHz BW, you might want to consider buying a LeCroy DDA-120 and the FPGA board of your choice. Replace the CRT with a $90 RPi display and use all that space to put proper anti-alias filters. A single channel at 4 GHz Nyquist is fast! I just bought a DDA-125 which already has the LCD display. I think now that a 120 and a 10" VGA LCD is a better option.There are two lines which have both an FPGA fabric and hard CPUs, the Zynq which is already in wide use for this application, and the Cyclone V.Probably most of the chip vendors have reference designs for AFEs for DSOs. If you want *really* fast, then there are ADC dev boards for a few $K which will give phenomenal results.

author: haastyle
author_rank: Regular Contributor
timestamp: March 08, 2019, 12:55:10 pm
content: The Haasoscope fits the bill, and is open source..https://github.com/drandyhaas/Haasoscope