I only recommend full manual routing. This is just my preference.
Did you create the schematic? If you want schematic design optimized straight to layout techniques, I've got a bunch & expect 8-12 layer designs to shrink down to 4-6, with 1/5th-1/10th the vias. (Note: I specialize in complex hand-held devices & compact high speed analog/digital processing modules.)
Your PCB meets similar pre-reqs which I use in many of my high speed processing modules.
To help guide you here, I need the following info:
Which size BGAs are you using? Must all your main ICs be BGA? (In optimized designs, I've found a lot of times that going back to QFP has actually shrunk the design?)
Can you mount components on both sides of the PCB?
Do you have a main processor, or is it an FPGA, or, a processor with an FPGA for SDram & bus control?
To what % peak clock rate are you using in the FPGA/SDram combination, are you using the DQMs?
Do you have an analog AD/DA sections, do they need to be quarantined, does it need to be on the same PCB?
____________ Brian Guralnick
----- Original Message ----- From: "Steve Allen" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Tuesday, November 02, 2004 6:54 PM
Subject: [PEDA] Board Layout Planning
Hi,
I'm using Protel 99SE and I'm preparing for an upcoming layout that promises to be a bit tight. It includes BGA's with 0.8 - 1.0mm pitches. I'd appreciate comments/suggestions relating to manufacturability and design.
Here's what I'm planning:
Manual route. I haven't heard many positive comments regarding 99SE's auto router.
BGA and fine pitch parts will be fanned out with a via for each pad.
Minimum trace width/clearance = 0.005/0.005" (0.010" inner layers).
Minimum annular ring = 0.005" (That is 20/10 vias).
Minimum hole size = 0.010"
Layers = 6 or 8
LPI Solder Mask
.062" Board Thickness
1oz copper
HASL/SMOBC
FR4
Here are some questions: What situations force the use of blind &/or buried vias?
How do I design BGA land patterns? I don't have manufacturer recommended land patterns. I've been using the on-line IPC calculator for leaded parts, but it doesn't appear to have BGA capability.
____________________________________________________________ You are subscribed to the PEDA discussion forum
To Post messages: mailto:[EMAIL PROTECTED]
Unsubscribe and Other Options: http://techservinc.com/mailman/listinfo/peda_techservinc.com
Browse or Search Old Archives (2001-2004): http://www.mail-archive.com/[EMAIL PROTECTED]
Browse or Search Current Archives (2004-Current): http://www.mail-archive.com/[EMAIL PROTECTED]
____________________________________________________________ You are subscribed to the PEDA discussion forum
To Post messages: mailto:[EMAIL PROTECTED]
Unsubscribe and Other Options: http://techservinc.com/mailman/listinfo/peda_techservinc.com
Browse or Search Old Archives (2001-2004): http://www.mail-archive.com/[EMAIL PROTECTED]
Browse or Search Current Archives (2004-Current): http://www.mail-archive.com/[EMAIL PROTECTED]
