Sampling above 50MHz

Help to track any bugs about DSView software
So I tried to take a trace of 25Mhz clock from SPI flash and if you sample at 50Mhz it works OK I compared it with Saleae logic analyzer if you go 100MHz and above results start to changes and it shows weird period 20MHz instead of 25MHz at 100/200 and 400MHz sampling results are different for the same signal. Looks like firmware update is needed? Yes I'm using latest v0.95 DSView. See attached samples.
Attachments
samples.zip
(221.33 KiB) Downloaded 204 times
rosin232
 
Posts: 1
Joined: Thu Dec 17, 2015 10:40 am

Hi rosin232,

Obviously, The clock you measured is not a 25M signal, the real frequency is about 19M.
With higher sample rate, you will get more detail of your signal.
For example, with 400MHz sample rate, per 2.5ns a point will be sampled.
with 50MHz sample rate, per 20ns a point will be sampled.

50MHz.png
50MHz.png (149.21 KiB) Viewed 1064 times
Andy
Site Admin
 
Posts: 149
Joined: Fri Jul 11, 2014 9:20 am


Return to Bugs Report

Who is online
Users browsing this forum: No registered users and 1 guest