Thank you very much for your kind comment, Peter!

@@PhilsLab The high frequency model of resistor shows that resistor has parasitic capacitance and inductance. The high frequency model of capacitor shows that it has parasitic inductance and resistance. Do the paraisitics of the components used for termination of high speed signals matter at all?

@@user-ww2lc1yo9c Yes they do, along with the land pattern of the component itself and if reference plane is voided below the pads or not.

@@user-ww2lc1yo9c ... and the high freq model of a chip inductor shows it has parasitic resistance and capacitance. So basically, at high frequency we only get one kind of component, a combo RLC. Greatly simplifies inventory.

Awesome, glad to hear that - good luck with your presentation, Julian! :)

Thank you very much!

Thanks a lot!

Thank you!

And what happens when you use a combination of both methods?

Thank you!

Thank you!

I'm self-employed so I get to work on a variety of projects. However, a lot of my learning takes place in my own time, where I'm trying to find new topics to deepen my understanding, improve my skills, etc..

Thanks! Getting stuck in what sense?

@@PhilsLab I was thinking BGA fanout for example or DDR routing.

Thanks! Yes, as stated in the video, place the resistor as close as possible to the driver/transmitter (e.g. at S for MISO, or M for MOSI - for point-to-point connections).

@@PhilsLab Thanks!

Thanks! Yes, that'll be a topic for a future video :)

Interesting that the series resistor (I assume a small value in comparison to the load impedance) at the receiving end still had a noticeable impact!

This is after the series termination resistor at the driver side (due to the potential divider 'effect' together with the transmission line).

A place to start thinking about this is comparing the wavelength (on a wire) of the highest frequency of interest versus the length of cable involved. Assuming audio max freq is 20kHz, wavelength in vacuum would be 300 M meters/20k = 15 km. Let's say on a wire the velocity is only c/2, so that's 7.5km. One rule of thumb is to start worrying about reflections if the length of wire exceeds 1/10 wavelength. So, if your wiring exceeds 750m, you could think about termination to address reflections -- so mostly not an issue. At 5MHz, vacuum wavelength would be 60m, so let's say 40m on coax. So termination starts being useful at 4m.

No. If you're talking about a resistor at the output of an op amp stage (and not included in the feedback loop) the purpose of that resistor is to reduce the effect of a capacitive load introducing an unwanted phase shift into the op amp stage feedback loop. The negative feedback loop is first a way to set the gain of the op amp stage to something useful, like 10. The open-loop op amp has a gain of say 1 million at DC, and there's built-in "compensation", which gradually decreases the gain vs frequency to 1 at some high frequency. This is because at some high frequency, the delay in the op amp starts to look like one half wave cycle time, so that the total feedback around your "negative feedback loop" ends up being positive. That is, the feedback arriving at the negative op amp terminal is in phase with the input signal. So the op amp is designed to have gain less than one at that frequency to avoid oscillation. But if you attach a capacitive load directly to the op amp output, that increases delay around the loop, and can result in reaching the positive feedback condition at a lower frequency where op amp gain is still >1, and oscillation results. So the series output resistor helps to reduce the delay effect of a capacitive load on the op amp output.

Some of the boards are on Git. Working on integrating some designs on the site with an Altium web viewer.

Haven't really seen that before.

PowerPoint with figures made with draw.io

Not something I've seen before to be honest.

Yes, but then the terminology is more towards 'matching', e.g. for RF designs - trying to match impedances to minimise reflections, but then to maximise power transfer. Also, loosely speaking, AC parallel termination can be seen as 'complex termination'.

Thank you