Ground Considerations for PCB Layout of Mixed Signal Designs Part 2

In this video series we look at considerations when laying out a ground plane on a PCB when working with a mixed signal designs. If you want to ensure you are making accurate noise free ADC measurements in your design this video series is a must watch.
Partitioning and Layout of a Mixed-Signal PCB www.hottconsultants.com/pdf_fi...
Grounding in mixed-signal systems demystified, Part 1 and 2
www.ti.com/lit/an/slyt499/slyt...
www.ti.com/lit/an/slyt512/slyt...

[@Rotwold]

Would be awesome if you added timestamps so viewers can skip parts they already know about. Also makes it easier to get an overview of the topics you're going to bring up in the presentation. Cheers for the great information shared.

[@kristoftunner9199]

Very good sources!! Thanks!

[@jenniferalves9653]

just noticed that 3rd type of ground plane should be "Isolated ground plane" but the slide title is still written as "segmented" and also mistakenly mentioned in the video starting timeline=12:37 on wards. fyi

[@onlyrgu]

I always look at recommended layout from the datasheet and add the screenshot in the schematics

[@RicardoDeSantiagoMusic]

That's a good idea :)

[@scottwilliams8539]

7:00 is nice for working out coupling between 2 high-speed signals and how you should separate them, but this doesn't help coupling from a low-speed (0-20kHz) signal return current spooling over and having conducted coupling with the high-speed return path. Low-frequency analogue signal return paths will spread over the entire board! :)

[@electricalychalanged4911]

Hi great video. I just started doing pcb layout's so this is really helpful. You always talk about hight precision measurements. I wonder if that really concerns me. I do nearly all of my measurements with the ads1115 module from adafruit. So I wonder if that is already high precious, we are talking 16bit resolution for max five V. Thanks

[@masterhost]

Hi.. Thanks for the video. I have a question, and thanks for your answer. The author of the article (and also you in this video) say that the return current try to flow underneath (in the plane under) the signal trace. What you mean "under the trace" physically? Are you talking about a 2 side PCB? what material is the "under the trace" made of, or this is just an ideal supposition??

[@ForceTronics]

The senarios you want to avoid is not having noisy return current either flowing next to a trace carrying a sensitive signal or above / below a sensitive signal on an adjacent layer. Between layers PCBs are typically made of an insulating material (FR4). But this insulating material can't stop a magnetic field caused by current flow from coupling on to a sensitive signal trace

[@Astartos22]

In the final example where the ground planes are completely isolated on the board, should they eventually be connected (perhaps at the GND terminals/connector of the PCB itself)? Or would you have separate GND terminals for different sections of the PCB?

[@ForceTronics]

The third example has the ground for each circuit isolated that is why you have to use something like an optoisolator to communicated data from one circuit to the next. This is typically used for precision measurement applications where you are making high resolution ADC measurements