Extreme PCB layout - DDR3 Interface

Рет қаралды 136,356

12 жыл бұрын

Combined version of the previous 2 videos. I didn't expect this video to actually work, sorry for the duplication.
Time lapse of a DDR3 Layout, taken at 1fps. Total time to layout ~38 hours. This is a very long video, check the index at the beginning if you don't want to watch the whole thing.
0:05 Component placement finalization
5:45 Bypass capacitor placement
16:40 DRAM via placement
18:10 DDR0 Address/Command/Clock
25:40 DDR0 data
35:10 DDR0 cleanup
37:05 DDR1 Address/Command/Clock
39:40 DDR1 data
47:00 DDR1 cleanup
49:00 Bypass capacitor placement, general routing
1:06:25 Length matching
1:12:30 Address/Command/Clock termination

Пікірлер: 141

@tesla500 10 жыл бұрын

The PCBs were $700 tooling plus about $10 per board. I had them assembled in China, cost was about $3k for PCB+assembly and $2k for components.This was for basically 4 complete sets of boards.

@mobileandroid5299 2 жыл бұрын

So, it did cost $5000 for 4 complete sets of boards? How many motherboards in a set? I'm so curious

@TheCrazyInventor 12 жыл бұрын

Good god, that's some impressive routing. Nice work. :)

@CodySmith 11 жыл бұрын

Oh and please make more videos, this is awesome to watch!

@Aussie50 12 жыл бұрын

wow thats a cool time lapse!, gotta play it on the 50" screen some day :D, looks like real geek art :D

@CostaExtranjero 11 жыл бұрын

Thanks for sharing! Subscribed! If there was a geeks Hollywood this would be an oscar nominee documentary. It would be better though, if there was some kind of narration over the video of you describing your line of thinking but I understand the hustle of doing this. Thanks again! Sorry for my English

@lazerusmfh 12 жыл бұрын

Love the Vids! Keep it up Tesla500. Informative, and cool to see.

@tesla500 11 жыл бұрын

Yes, based on what pads are nearby and how many other nearby pads and vias there are of the same net. This one (0.8mm) is more difficult than a regular 1mm pitch part because you can't put 1 via for every power pin, you have to select how the vias are allocated quite carefully.

@drkblde42 10 жыл бұрын

The main reason to place vias on a grid system within a BGA is to alow all traces to exit the BGA and be centered inbetween the vias when routing out. It also forces the traces to be on a 45 when entering thusly avoiding acid traps and the dreaded 90* angles.

@lazerusmfh 12 жыл бұрын

@dnbrhythm Sweet. I've enjoyed the video layouts that you post. they are informative from a layout standpoint keep it up!

@alextrofimov7947 6 жыл бұрын

I learned a lot. Thank you very much.

@tesla500 12 жыл бұрын

@envisionelec I got several access violations, at least one was caught by the screen capture, but it's hard to see it at full playback speed. Luckily I haven't lost any data because of them, the save function still worked after the access violation.

@tesla500 10 жыл бұрын

Thanks for the insights. I'll admit this was my first go at something like this. 1) What do you mean? This is 0.8mm. 2) This would be ideal, but it was not called for by the TI design rules for this "low speed" 400MT/s design, and would have added more layers == more cost. 3) The rules state a spacing of 3*trace width, but you're allowed to reduce that to 1*w for up to 25mm of trace length per rout if required. I would have been very much more careful for a 1600MT/s design for example.

@ibrahimozgursucu3378 3 жыл бұрын

"Why are motherboards so expensive, aren't they just a plastic/cardboard'y plate with some conductive lines printed on them?" //Watches video// "How are motherboards this cheap!"

@Bianchi77 5 ай бұрын

Nice info, thanks :) 👍

@poorchava 11 жыл бұрын

Nice video. How much did it cost to fabricate the pcb? Multilayer ones tend to be epensive as hell. Did you assemble the BGAs yourself or outsourced that too?

@ManiDProductions 10 жыл бұрын

i'm just about to start doing the same thing...thanks for the video

@sanches2 11 жыл бұрын

@tesla500 Dude, you're my hero :) idk, sometimes fan-outing these over 400ball devices makes me wanna scream. I had only 2 similar projects in my life untilnow and they are at least twice as less complicated. Just one question: how do you estimate your time when speaking to you manager/customer? and do you prepare your libraries for yourself or? Your action was really inspirational for me, Thank you!

@thomassui4879 Жыл бұрын

I have one question which confused me for a while, when I see a bga ic, how many layers of the board should I expected for? like minimum of 6 layers, maybe 8 or 10 layers? But then how should I give a purpose of each layer? even thought I watched many videos, still not sure which layers should be GND, and which are should be SIG/PWR. If I made a bad selection, which means I may spend all my time for nothing. Please explain some like that, thank you.

@sanches2 11 жыл бұрын

that was a really nice remak:)

@cavosk003 7 жыл бұрын

Great work! But why haven't you used the via-in-pads?

@tesla500 12 жыл бұрын

@dnbrhythm I guess you could call it that, it has a lot of the same things that a PC motherboard has, and is similarly complex to design. It could be used as a single board computer running Linux or Android, but it's really designed just for the high speed camera.

@drkblde42 10 жыл бұрын

I appologize for not catching that it was a .8mm grid. You should have kept vias on a .8mm grid then. Unless this was a 2 or 4 layer board there would have been ample room to route the address and data traces on seperate layers. Careful planning allows for minimal layers. Something that many PCB designers fail to be taught or realise is that Design rules are the minimum a board needs to perform... not perform well. It is always good to see other designers working though. Thumbs up man.

@AdamSkriver 11 жыл бұрын

Cody, there are quite a few free PCB layout programs available and lots of examples to get your feet wet. One of the guys on All Programmable Planet recommended gplEDA. In the video tesla500 is using Altium Designer which is in the thousands of dollars per seat range. You may want to check out Advanced Circuits, they also have a free PCB layout tool that could help you out.

@tbbw 11 жыл бұрын

Dear mother of god... you sir deservs a thumbs up.

@ebubekircagrsen7824 8 жыл бұрын

Do you have any advice to start PCB design for newbies just like me ?

@tesla500 10 жыл бұрын

To make the shorter connections longer so they're all the same length.

@AdamSkriver 11 жыл бұрын

@tesla500 Do you lay down your vias in the BGA and then assign them nets?

@envisionelec 12 жыл бұрын

38.5 hours and no Access Violation Errors? That's the real miracle.

@shiweiluan 8 жыл бұрын

For DDR3 layout on 8 layer pcb, is it good to place tracks on inner layers with through via since some stubs can be created? Thank you.

@dd5087 7 жыл бұрын

yes, but maybe 10 layers is more appropriate, high speed signals should always be between power planes. Download this design kit from atmel and open the gerber files folder with gerbv or other gerber viewer software. you will see how power planes and signals are placed. www.atmel.com/images/ATSAMA5D3-XPLD__KitsFiles.zip ps. cool video!

@user-gm7if5zv6e 7 жыл бұрын

MAIN QUESTION - DID IT WORK ???????????????

@al19527 7 жыл бұрын

wow and I was worried about cross talk in my high speed board, if this works, I'm not worried any more, you really need to worry about cross talk even in your serpentine tracks

@CodySmith 11 жыл бұрын

Where could one begin to learn PCB layout such as this?

@casiothestrong 9 жыл бұрын

Any chance we can get a legit version of this video? Not a time-lapse? I would probably watch the whole thing in 1 sitting. lol

@tesla500 9 жыл бұрын

Only recorded the video at 1fps, so I can't do anything better than this :( I do have unreleased footage of the FPGA routing and some more from this board, I just need to cut that all together.

@qwertboyo 8 жыл бұрын

Matthew Auld playback at .25 in the settings [get 4 fps rather than 16] , close to that original fps, occasionally pause when there's a window pop up.

@brooklyncarter4807 7 жыл бұрын

Matthew Auld right

@KWIer1 8 жыл бұрын

Hello, can you publish final PcbDoc file? Thanks in advance

@tiburciolapanak 11 жыл бұрын

what software do you use?

@ckalas 11 жыл бұрын

why make some of the connections wavey?

@_BangDroid_ 7 жыл бұрын

Greetings from Unicornia!

@Bomag 7 жыл бұрын

How come some of the traces are made to be wiggly? I'm guessing there's a reason behind it other than just because it looks so cool.

@imeakdo7 6 жыл бұрын

Adam Rhodes its to increase path length

@ryanoconnor7957 9 жыл бұрын

Wow this is crazy, why didn't you just press the autoroute button and then tweak that?

@SeanHodgins 8 жыл бұрын

+Ryan O'Connor Never use auto-route. That should be on a t-shirt.

@lazaraza 8 жыл бұрын

+VintageMayo 9 out of ten?!.. hahaha, should be 99 out of ten :D

@totoxahc 8 жыл бұрын

Did it work?

@Ncky 8 жыл бұрын

What are you making here? SBC or Video card? What?

@pufero1 8 жыл бұрын

+N!cky high speed camera.

@Sirus20x6 11 жыл бұрын

im routing a .4mm pitch wlcsp package now. that's point 4 mm :(

@salehhabibian9262 4 жыл бұрын

I watched this video in slow motion :)

@fatih4utr 8 жыл бұрын

i cant understand Length matching section , what is for ?

@benvrakas6665 8 жыл бұрын

+fatih şerefli its so the electrical signals between the CPU and ram arrive at the same time

@arlenalem 10 жыл бұрын

HI, could you tell me which company have you contacted?, and what's mean $3k?sorry for this basic question

@tesla500 10 жыл бұрын

Not quite sure what you're asking. Contacted a company about what? Where did I mention $3k?

@arlenalem 10 жыл бұрын

tesla500 sorry, mmm I meant wich company fabricated the PCB, and the other question was about $3k, You have used this in the answer to Rafał Mróz "The PCBs were $700 tooling plus about $10 per board. I had them assembled in China, cost was about $3k for PCB+assembly and $2k for components.This was for basically 4 complete sets of boards"

@tesla500 10 жыл бұрын

arlenalem I got them made at OurPCB. Pretty decent quality, and about 1/3rd the price of doing it locally

@arlenalem 10 жыл бұрын

tesla500 Hi, Thanks for answer, Did you design the PCB Stackup? or you ask suggestion from the factory?,I've finished a pcb (6 layers) and I send a message to a factory from china requesting a pcb stackup suggestion, track geometry, but they asnwered "PCB is OK" but regard to pcb stackup they said "Actually we can not send you the suggestion of impedance control.Because we do not know about the performance,function or application of the finished product.You can just check the circuits and decide the impedance control tracks according to the function of the PCB.Thanks.", so I have to design the pcb stackup? Sorry for my question but , It will be my first multilayer board, and practically i'm a biggenner for pcb manufacturing, thanks in advance

@tesla500 10 жыл бұрын

arlenalem I prefer to plan out the stackup before layout, so all the trace/space sizes are known beforehand. Due to some complex track configurations (broadside coupled differential stripline on one board) I simulated the stackup in Hyperlynx and came up with a suitable one. For simpler boards, there are numerous calculators online, search trace impedance calculator. Those don't really help you chose a full stackup though, it was difficult for me the first time too. OurPCB basically said the same thing your supplier did, but eventually sent me some example stackups from other customers, however those weren't that useful. Having an example helps. Basically, you can select layer thicknesses in about 0.05mm increments or thereabouts. As a starting point, use 0.15mm on the outside layers, and 0.1mm on inside layers between the signal layers and the ground plane if you want 50ohm with 0.1mm traces. An example for 6 layer board may be the following, which will give you 50Ohm single ended impedance with 0.15mm traces outside and 0.1mm inner layer traces. Top layer 0.15mm core Mid-layer 1 (Power/Ground plane) 0.1mm prepreg Mid-layer 2 (signal layer) 0.9mm core Mid-layer 3 (signal layer) 0.1mm prepreg Mid-layer 4 (Power/Ground plane) 0.15mm core Bottom layer

@Tab54o 7 жыл бұрын

we went from pads to altium at work and in altium all the same things take 4x longer to do because of all the crap on the menus and it's clunky interface. pads has bus route matching differential pairs all automatic or assisted routing and pads is a million times easier to use. took my boss a week top do a simple board what I could have done in a matter of hours.

@zeeriew2966 10 жыл бұрын

1 frame/sec --- for ~38 hrs. wow! I hope I can watch this video as normal 30 frames/sec speed. Then it will really be helpful. Thank a lot though...

@rokhribar5512 5 жыл бұрын

Damn, so you can design a motherboard?, Isnt that like impossible ...

@BxBallinz 5 жыл бұрын

What do you study to learn this concept?

@tesla500 5 жыл бұрын

Electronics Engineering

@Tab54o 7 жыл бұрын

I bet you could have done this is 1/4 the time using a PADS or Xpedition suite from Mentor Graphics.

@tesla500 7 жыл бұрын

What features do those packages have that would make manually routing this 4x faster? Altium now has proper multidrop bus length matching, it didn't when I routed this.

@RSuarez66 7 жыл бұрын

I have used Pads and currently use Altium, and definitely true. There are a lot of things that are done much easier with PADS than with Altium.

@beratmeral3501 7 жыл бұрын

You are right. PADS Router is more user friendly for this kind of messy routing stuff.

@zidanm969 6 жыл бұрын

what is the name of the programme you use in this video

@zalethorlaphet8791 11 жыл бұрын

Whait, you can design motherboards? Can i hire you?

@coolwinder 9 жыл бұрын

What program is that?

@iwave000 9 жыл бұрын

Altium

@uriahsky 12 жыл бұрын

I thought something like this would take a room full of people working for months but one guy and 38 hours??

@khairilumam9524 10 жыл бұрын

woa.... manual routing.... I'm Spechless...

@dumle29 9 жыл бұрын

You always route boards manually...

@xeno126 9 жыл бұрын

dumle29 Are you sure? I autoroute a part then clean it, then the next one and so on.

@dumle29 9 жыл бұрын

Xeno Honestly it depends. Some things can be done with autorouting, but it's honestly limited.

@xeno126 9 жыл бұрын

dumle29 Like what's the limit? I've never worked on something very advanced or high speed so I'm not sure.

@dumle29 9 жыл бұрын

Xeno I'm no expert, and there's no doubt somewhere where autorouting is a better option than manual routing, but for the most part, things are either so simple, that you might as well manually route them, or so advanced that an autorouter won't do the job. Autorouters are mainly used where something is really simple, but there's a lot of tracks to route. Something like an oldschool array of memory chips, and old double-sided throughhole PCBs, EDIT: which run at fairly low speeds, where signal integrity isn't too much of a concern.

@meditator8387 9 жыл бұрын

Design technique of pads.

@rocksntwigs 8 жыл бұрын

Might want to try to cut 4:32 dude. Nice video though.

@jamaldope 8 жыл бұрын

"My Little Pony - Friendship is Magic" HAHAHA This dude is a brony

@GeorgeTsiros 8 жыл бұрын

not the most ridiculous thing i've downloaded to watch with my gf. At least MLP is relatively well-written. Try sailor moon... or "candy-candy".

@Ncky 7 жыл бұрын

my little pony :) now you got answer, he have daughter

@Phoen1x883 7 жыл бұрын

He's never gone to any great lengths to hide it. His Digital Micromirror Devices video even uses Twilight Sparkle's cutie mark as a test image.

@kdgdirk 12 жыл бұрын

cowabunga dude, this is minecraft meets snakes...lol

@pateljp01 11 жыл бұрын

Hello Tesla500 this is a great Video. This can help so many pepople who are learning them self. Is it possible to have your design file.? Can you please upload your design pleaseeeeeeeeeeeeeeeeeeeeeeeee.....

@Vidicon31 12 жыл бұрын

i think it is altium designer

@axlkhan7186 5 жыл бұрын

Shiba Tatsuya IRL

@shawnmoss9322 9 жыл бұрын

This is excellent work! I have some new projects I would like to run by you and see if you are interested. How much do you charge for this type of "high speed" design and layout? Do you have an email address I can contact you at? Thanks! -S

@williefleete 7 жыл бұрын

Man that is crazy. I would have just put everything basically where I wanted it and hit auto route

@milad9535 7 жыл бұрын

No offence, but Auto routing is the most primitive step in routing a PCB. PCB routing is an Art by itself alone.

@HavanaWoody 7 жыл бұрын

the irony of redundancy in that reply lol

@williefleete 7 жыл бұрын

smm mm I figured auto-route will only get you so far

@milad9535 7 жыл бұрын

Yes man, That's totally right, I'm saying this after 10 years of PCB design and I've seen the difference. I'm also partly aware of what kind of algorithms they use for auto routing like alpha beta purging or A* search, and their drawbacks in a real PCB design.

@SomeRandomPerson163 11 жыл бұрын

So hardcore...

@ernestchung4633 11 жыл бұрын

Balance bike

@NoNameAtAll2 2 жыл бұрын

dance dance revolution players are too advanced nowadays...

@Dexter101x 8 жыл бұрын

Does no one use auto-route?

@adriandeveraaa 7 жыл бұрын

its a bad habit. manually routing is far better and a better optimized design overall.

@Phoen1x883 7 жыл бұрын

What downsides does manual routing have? What do you mean by optimized?

@Dexter101x 7 жыл бұрын

Phoenix I know, it's strange that auto isn't optimized or you can't adjust the tracks later

@Phoen1x883 7 жыл бұрын

I'm not trying to argue, I legitimately don't know. I don't have any PCB layout experience. Is being unable to adjust the layout afterwards just a software limitation, or is it something more complex? And what do you mean by optimized?

@Dexter101x 7 жыл бұрын

Phoenix You can adjust afterwards, just use the M or G shortcut keys to move tracks/components. I have altered the traces and components to make it more compact and "optimized"

@aneeshprasobhan 7 жыл бұрын

one word....*autoroute* B)

@firmman4505 3 жыл бұрын

seems like an AI should be doing this.

@DiegoColl44 9 жыл бұрын

Santiago Millicay Bruno Alejo Contreras lucas baginay paez lucas exequiel ibañez

@andreylapshov5716 2 жыл бұрын

Are u copying other Pcb?

@drkblde42 10 жыл бұрын

Three things... 1.) you really should pin escape vias spaced on a 1mm grid in a BGA 2.) data and address busses should be routed on different layers 3.) you should leave15-20 mils minimum spacing between traces The work above is really... low performing work and sloppy to be honest. Signal integrity could be vastly improved by keeping the above three things in mind my references for the 3 above? How about my experience working on 20-30gbps 20-30 layer boards.