LART hardware distribution version 0.95 (March 20, 2000)
--------------------------------------------------------
Copyright (c) Jan-Derk Bakker 

= Contents
==========

0) Introduction
1) Distribution content


= 0 Introduction
================

This is a pre-release release of the hardware design files for the Linux
Advanced Radio Terminal (LART). LART is a self-contained StrongARM-based
embedded board targeted at low power applications that require high performance.
See 

http://www.lart.tudelft.nl

for more information.

= 1 Content
===========

This distribution currently only contains the Gerber PCB design files for LART.
Future versions will include a Bill of Materials (BOM), the schematics and
component placement files.

The six-layer PCB is defined by sixteen Gerber files:

l1_silk.gbr  Component side silkscreen
l1_mask.gbr  Component side solder mask
l1_pos.gbr   Component side positive copper
l1_neg.gbr   Component side negative copper
l2_pos.gbr   Layer 2 positive copper
l2_neg.gbr   Layer 2 negative copper
l3_pos.gbr   Layer 3 positive copper
l3_neg.gbr   Layer 3 negative copper
l4_pos.gbr   Layer 4 positive copper (starting to see a pattern yet ;-)
l4_neg.gbr   Layer 4 negative copper
l5_pos.gbr   Layer 5 positive copper
l5_neg.gbr   Layer 5 negative copper
l6_pos.gbr   Solder side positive copper
l6_neg.gbr   Solder side negative copper
l6_mask.gbr  Solder side solder mask
l6_silk.gbr  Solder side silkscreen

These files work for me, but as the LICENSE states, YMMV. I strongly urge you to
check the files in a Gerber preview program (like gcprevue) before sending them
off to a board fab house. I personally use the DOS version which can be found at
http://www.apcircuits.com/html/software.html ; a Windows version (with IMHO a bad
case of featuritis) is at http://www.graphicode.com/datasheets/gcprevue/
I don't know of any free Gerber viewers for Linux.

To increase the likelihood that you will get what you want, I've included 
Postscript previews for all layers, in the files

l1_silk.ps  Component side silkscreen
l1_mask.ps  Component side solder mask
l1.ps       Component side composite copper
l2.ps       Layer 2 composite copper
l3.ps       Layer 3 composite copper
l4.ps       Layer 4 composite copper
l5.ps       Layer 5 composite copper
l6.ps       Solder side positive copper
l6_mask.ps  Solder side solder mask
l6_silk.ps  Solder side silkscreen

BIG FAT WARNING: I strongly urge you to 1) preview the Gerbers and the PostScript
yourself and look for discrepancies, and 2) send a hardcopy of the .ps files to
your board manufacturer as a 'proof'. It's the path with the smallest probablity
of ending up with expensive PCBs that function as great near-zero Ohm resistors.

Oh, and PCB fab houses really want the Gerber data, the .ps files alone are no 
use to them.

The file drill.ncd holds the drill data in Excellon format.

If you want an estimate on the PCB cost, try http://www.4pcb.com . I have
absolutely no experience with them, but their on-line calculator will give a
reasonable cost breakdown. The PCB parameters are:
 six layers
 (about) 3"x4"
 miminum trace width 0.006"
 minimum hole size 0.012"
 minimum SMD pitch 0.020"
 about 700 holes
 about 1000 SMD pads

- Bill of Materials
I've no full BOM yet, but these are the most important components for LART. The
prices in parentheses are my guesstimate of what you would pay for these
components in small quantities in $US.

- (1) SA-1100 in LQFP-package. The board supports all speed grades and core
  voltages. ($60-75)
- (4) 4Mx16 EDO DRAM chips in TSOP-II package. Micron, ISSI and others make
  these. ($16-20)
- (2) Intel DT28F160F3B Fast Boot Block Flash devices ($10-20)
- (1) Maxim MAX1626ESA step-down converter for the I/O voltage ($4)
- (1) Maxim MAX1627ESA step-down converter for the core voltage ($4)
- (1) Maxim MAX3223ECAP RS232 transceiver ($4)
- (1) Maxim MAX811SEUS Microprocessor supervisor ($3)

I have had moderate amounts of luck getting components out of
http://www.avnetmarshall.com ; other possible sources include
http://www.arrow.com, http://www.ied.pios.com and http://www.wyle.com

It is *very* advisable to get a hold of these components before building a PCB.
My own experience has made me cynical: I don't send a PCB off to a fab house
before I have the critical components on my desk. All other components
(connectors, decoupling caps) are available through distributors like Farnell
(http://www.farnell.com).

If you have any more questions, don't hesitate to ask.

Jan-Derk Bakker, bakker@mmc.et.tudelft.nl
