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Motherboard Design Process
MBRFan writes "MBReview has posted the latest revision of their 'Motherboards - The Designing Process' article. This article covers the design process for modern motherboards, and also goes over some of the most common components that can be found. Definite read for information lovers, though beware, it'll take a while to read!"
if they also gave a little insight into what goes into the manufacturing process as well. After all, you can design the best board there is, but if you have trouble making it in large quantities, it's not going to be successful. Cost and ease of manufacture should be factors in any engineering decision.
Monstar L
I used to design motherboard power system components, and the author spends a good bit of time talking about that. That is actually the most complicated part of the board design, as it is not at all automated. Most component vendors try to sell a complete solution to the motherboard vendor, easing their job somewhat while helping the sales of the component vendor.
One particularly interesting item of note: all those capacitors the author describes are absolutely crucial, and together form one of the largest cost items on the board. The system is tested using a processor-vendor-supplied "load tool" which simulates the worst case load transients one can ever expect to see. Most of that testing is done by the power system component vendor and then provided as a block to the motherboard vendor. Most motherboard vendors have no idea what they are doing there.
In fact, a lot of the foreign manufacturers (no names) cost-reduce their designs by simply pulling out caps until the system blue screens. Then they put the last one back in and sell it. Intel is the only manufacturer I am aware of that actually sells the worst-case performing design.
Note that I am only aware of products related to Intel-type motherboards. I never worked on the othe stuff.
Just my $0.55 (US inflation, 1774-2008, for $0.02)
All in all a motherboard is a complicated piece of electronics so it isnt surprising that bugs sometimes creep in. As with software I expect it is the quality of the engineers working on it that is the ultimate deciding factor in the quality of the final product.
gmail invite
Every single component on a motherboard can be a magnificient piece of work, but it deals only with a limited number of variables. A CPU or chipset component ultimately only deals with bus protocols and internal design. The same goes for other components like memory or harddrives.
But everything comes together through the motherboard, and that (in my eyes) makes it the hardest part of a system to design well, considering the number of variables. A truly well done MB design is really a piece of art.
Yes... but does your motherboard manufacturer follow best practices like Feng Shui?
Take-off every
LOL, I'd like to see them try and make a single-layer motherboard!
...comes with the wisdom of the Far-East, yessir!
What, you haven't heard of the Feng Shui Motherboard?
I only post comments when someone on the internet is wrong.
That article kicks ass. I feel smarter already. I never knew EMI and line noise was such a problem for MoBo designers.. What a bitch that must be
How does crap like this get modded insightful? There are many factors involved in a production process such as motherboards. In many cases trade offs will have to be made between engineering, manufacturing and cost. If the AC who feels maufacturers are not doing the job properly may I suggest he/she/it puts forward a better design than can be mass produced and afforded by the general population
Do not try to read the dupe, thats impossible. Instead, only try to realize the truth
What truth?
There is no dupe
IANAMBD, but...
... I.e the thickness of the "Prepeg"
"trace" == Metal tracks carrying the current
"Prepreg" == insulating "silk" layer separating the metal tracks running above and below.
"static impedance" == "guess" they mean parasitic capacitances formed between the tracks crossing over each other, separated by the "Prepeg".
"Er, or dielectric constant" == See physics book for parallel plate capacitor, the 'E' is the "greek epsilon"
"height of the trace" == the plate separation
.
The guy who wrote this article has a glittering career in the Patent business.
PC motherboards typically have 4 - 6 layers. That's pretty complicated. Think about routing all of the signal lines of the PCI (64-bit) bus and memory bus. If you have AGP nad PCI-X, add those in ther too. Think of all the signals going from your IDE ports and SCSI ports (if you have them) to your chipset. If you have an opteron, you have in the neighborhood of 940 pins. They all get connected. That's a lot of nets and a lot of routing!
And, it's a good thing to reduce board layers to a certain point because adding layers gets expensive! While it does complicate the process, the process of routing the board is a one time process and thus a one time cost. Once the board is routed and tested, it's off to manufacturing where the cost of extra layers is recurring. It does complicate the manufacturing process in that now you have to glue together more layers after routing them. This is why more layers get so expensive. Those layers have to line up. With nets getting as small as they do, there is almost no room for error in lining these layers up. Very difficult. The more layers you add, the more likely you are to have layers aligned improperly. Someone has to eat the cost of those boards that cannot be sold and it wont be the manufacturer.
To save the other metric readers the trouble googling, 1 mils = 1/1000 inch = 2.54e-5 metre. conversion
Basically what you're saying is...