Originally posted by: f95toli
Also, designing a PCB can than can handle those speeds will be very,very,very difficult. You definitly need a multi-layer board with several ground- and power layers (=very expensive).
This will be a VERY expensive project.
agreed. i dont think you realize just how expensive its going to be. i design and order PCBs on a weekly/biweekly basis and it isnt cheap no matter how you look at it. you are looking at a service charge of 75 dollars and then its around 20 cents per square inch for a 2 layer board, and that doubles for every next even number of layers, so its 40 cents per square inch for 3 or 4 layers, 80 for 5 or 6, etc. you are going to need at LEAST 8, so you are looking at 1.60 per square inch. a cd is 120mm in diameter, so lets just say its a square with 120mm sides, that gives you 14400mm^2, which is roughly 22in^2. at 1.60 per square inch, you are looking at 35 dollars per board.
35 dollars per board gets you a barebone PCB. no solder mask (the green stuff that makes it 100000x easier to solder tiny parts on (i should know, i do this on a daily basis including 128-200pin microcontrollers)) or silk screen (the writing and component ghost on the solder mask). that 35 dollars gets you a bare piece of copper with conductive traces and planes sticking around everywhere, and you cant have that...so you have to get at least the solder mask and if you plan on soldering the components on yourself, you have to get the silk screen as well since it makes it much easier (and by much easier, i mean much much easier). that doubles the price of each board, so you are up to 140ish dollars for 1 board, 200ish for 2, and keep adding 60-70 dollars per board until you get to 50, then you lose the core charge and you get a little bit of a price reduction.
next, you are going to make mistakes big time on the first revision or two. not because you are stupid but thats the nature of the beast. you are going to draw traces wrong, get the wrong parts, get the right parts in the wrong packages, forget to get the vias plated on the interior (this is not the default option sometimes), draw the pads incorrectly or overlap silk screen text, make mistakes regarding the power radiating from bigger components introducing noise into the circuit, and the list goes on and on. so its going to take you at least 3-4 revisions to get it working the way you want (it may work on the first go, which isnt ultra rare, but you will more than likely not get this since its your first time).
if you are accepting of the info i just told you and think you have the motivation to get it done, then i say more power to you and i will help you as much as humanly possible should you ever need it...i just hope you are prepared for it because its a long road and can be very frustrating. you have a great idea IMO and id love for you to see it through to the final product.