What is the purpose of these squiggly traces?

[unbuildpain]

What is the purpose of squiggly traces? These can be noticed between the CPU socket and RAM sockets in the following photo:
They hardly seem to cause any delay, so why? They appear very similar to the antenna patterns of USB adapters, can these also emit signals?

 

[FvM]

In case you are referring to the meanders in this clip, there exact purpose is delay matching of multiple signals in a data bus.

 

[unbuildpain]

Yes, I'm referring to those. Will they cause any delay?

Can they also generate signals?

 

[FvM]

Delay matching implies causing a delay...

I guess you want to ask about radiating rather than generating a signal. Only active components, e.g. transistors can generate a signal.

A trace upon a ground plane doesn't radiate significantly. Printed antennas use trace structures without ground plane below. Refer to the photos you posted in your other thread.

 

[unbuildpain]

Delay matching implies causing a delay...

I guess you want to ask about radiating rather than generating a signal. Only active components, e.g. transistors can generate a signal.

A trace upon a ground plane doesn't radiate significantly. Printed antennas use trace structures without ground plane below. Refer to the photos you posted in your other thread.

Thanks for making me aware of the correct word to use for it. With paint over the PCB, how can we know if there is a ground plane below it or not?

If Transistors can generate signal, motherboard would be filled with them. Is there a way to find their frequencies or subdue them?

 

[KlausST]

Hi,

Thanks for making me aware of the correct word to use for it. With paint over the PCB, how can we know if there is a ground plane below it or not?

a motherboard consists of several copper layers. And a motherboard is a HF design. The chip manufacturer usually provides a full design guide how to design a motherboard. Do a search - maybe you find it.
Btw: I never needed to know if or where ther is a GND plane in a motherboard. I just used it.

If Transistors can generate signal, motherboard would be filled with them.

There are. Millions. Hidden under black plastics.

Klaus

 

[unbuildpain]

Hi,


a motherboard consists of several copper layers. And a motherboard is a HF design. The chip manufacturer usually provides a full design guide how to design a motherboard. Do a search - maybe you find it.
Btw: I never needed to know if or where ther is a GND plane in a motherboard. I just used it.


There are. Millions. Hidden under black plastics.

Klaus

I have searched for motherboard design guide for the motherboard mentioned in this thread and I couldn't find any. What terms would you use to find it?

Even I wouldn't have cared for it, had it not been for stupid and suspicious things happening.

If there are millions, could it possible for them to work in conjunction to produce or receive signals?

 

[KlausST]

Hi, I searched for "motherboard processor design guide"

and one of the most first links was this: http://application-notes.digchip.com/027/27-45911.pdf

Klaus

 

[wwfeldman]

the millions of transistors Klaus is referring to are in the integrated circuits - the black plastics
and they certainly do work in conjunctions and send and receive signals, calculate, move data,
ansd all the ohter things any of our electronic gadgets do

 

[unbuildpain]

the millions of transistors Klaus is referring to are in the integrated circuits - the black plastics
and they certainly do work in conjunctions and send and receive signals, calculate, move data,
ansd all the ohter things any of our electronic gadgets do

I meant wireless signals, can they utilized to send and receive wireless signals? Not specifically built for wireless communication, but any regular IC which has transistors but can has transistors.

 

[KlausST]

Hi.

Be sure there is no hidden wireless on your motherboard.
Nobody will steal informations from your PC (unless you carelessly send them via internet).
A metal PC case is shielded , thus it's almost impossible to send/receive wirelessly informations from/to the motherboard.
And if we just imagine there is some hidden wireless on your motherboard, then the range would be very limited. Your "enemy"needs to wait outside the window and wait for you to use the PC. And what can he expect to gain? Do you hide that extreme secrets that makes it worth to spend the effort?

It's more likely that you installed an app on your cellular telephone that misuses your address book, location tool, microphone, browser ... to get your informations. But they mainly are not interested in individual informations but crowd informations.

Don't be hysteric. Nowadays many people "try" to hide their data. They refuse schools, kindergardens, sport clubs to post photos on their web site (without names or detailed informations) ... but the same time they spread all their movements, discussions, photos, private informations ... carelessly via the social medias.

Klaus

 

[unbuildpain]

Hi.

Be sure there is no hidden wireless on your motherboard.
Nobody will steal informations from your PC (unless you carelessly send them via internet).

That is impossible going by my experience.

A metal PC case is shielded , thus it's almost impossible to send/receive wirelessly informations from/to the motherboard.
And if we just imagine there is some hidden wireless on your motherboard, then the range would be very limited. Your "enemy"needs to wait outside the window and wait for you to use the PC. And what can he expect to gain? Do you hide that extreme secrets that makes it worth to spend the effort?

Whether a metal can shield or not depends on it's conductivity, if it has low conductivity it's as good as transparent in the radio frequency and these cases have openings too. You have a smartphone which is so small it fits in your pocket, and it has limited battery capacity, it is a able to send a signal which able to reach cell tower which would be approximately 1 kilometer away, and it will also be able to send a signal to reach WiFi which would also be some meters away. I have to agree with you that if there is some undisclosed wireless technology inside my motherboard, miscreants using it will have to be nearby.

It's more likely that you installed an app on your cellular telephone that misuses your address book, location tool, microphone, browser ... to get your informations. But they mainly are not interested in individual informations but crowd informations.

Don't be hysteric. Nowadays many people "try" to hide their data. They refuse schools, kindergardens, sport clubs to post photos on their web site (without names or detailed informations) ... but the same time they spread all their movements, discussions, photos, private informations ... carelessly via the social medias.

Klaus

I don't use smartphone and I don't do any such things.

 

[wwfeldman]

sounds like you need to put yourself and your electronics inside a Faraday Cage

 

[unbuildpain]

Delay matching implies causing a delay...

I guess you want to ask about radiating rather than generating a signal. Only active components, e.g. transistors can generate a signal.

A trace upon a ground plane doesn't radiate significantly. Printed antennas use trace structures without ground plane below. Refer to the photos you posted in your other thread.

I've checked motherboards I could find and they don't have ground plane, I can see the same pattern on the front and back.

 

[KlausST]

Motherboards have more than 2 layers (TOP and BOTTOM).
They are multilayer PCBs. Often 8 to 12 layers of copper.

Klaus

 

[FvM]

I've checked motherboards I could find and they don't have ground plane, I can see the same pattern on the front and back.

Very unlikely. You can look through the board to identify regions without planes. Usually there are none.

 

[unbuildpain]

Motherboards have more than 2 layers (TOP and BOTTOM).
They are multilayer PCBs. Often 8 to 12 layers of copper.

Klaus

Very unlikely. You can look through the board to identify regions without planes. Usually there are none.

If I'm seeing squiggly patterns are on the front and back at the same place, doesn't it mean the trace is on the top and bottom layers or extending through all the layers? Why would a path require traces on the top and bottom, wouldn't 1 be sufficient? I was reading an electronics textbook and in that it was mentioned that regardless of the shape of a copper wire, electricity travels at the same pace, they gave an analogy of pipe or tube filled with balls and when a ball is inserted at one end, at the other end, a ball eject almost instantaneously, so what kind of delay will squiggly traces like that cause?

 

[KlausST]

If I'm seeing squiggly patterns are on the front and back at the same place, doesn't it mean the trace is on the top and bottom layers or extending through all the layers?

they may look identical, but I´m sure the traces carry different signals on top and on bottom.
Next to the bottom layer there should be a GND layer. Next to the top layer there should be a GND layer, too.

I was reading an electronics textbook and in that it was mentioned that regardless of the shape of a copper wire, electricity travels at the same pace,

True, same pace, but different length means different time. And those meander traces surely are longer than a straight trace.

when a ball is inserted at one end, at the other end, a ball eject almost instantaneously, so what kind of delay will squiggly traces like that cause?

Almost instant. But it takes time. For a raw estimation you may calculate with about 60% of c (speed of light)

Klaus

 

[unbuildpain]

they may look identical, but I´m sure the traces carry different signals on top and on bottom.
Next to the bottom layer there should be a GND layer. Next to the top layer there should be a GND layer, too.

True, same pace, but different length means different time. And those meander traces surely are longer than a straight trace.

Almost instant. But it takes time. For a raw estimation you may calculate with about 60% of c (speed of light)

Klaus

How exactly can I verify if there is a ground plane or not? Maybe the traces don't require a ground plane?

 

[betwixt]

How exactly can I verify if there is a ground plane or not? Maybe the traces don't require a ground plane?

Not all traces do need a ground plane but I would guess there is one covering most of the area of the board on one of the internal layers. The only way you can see for yourself is to take an x-ray picture. That's what they do in production facilities for checking the board and solder joints under components.

Regarding the meanders, they may not seem to have much effect but consider that memory and CPU timing is measured in nS and an electrical signal takes about 1nS to travel 30cm along a copper trace. You can see that the meanders can extend the trace length quite significantly and hence create significant delays. Don't think of the delays as just wasting some time, they are there so that signals arrive at the correct times from different places on the board, otherwise they would get out of synchronism with each other.

Brian.