====== PCB Design Guidelines ======

==== Eagle PCB editor device guidelines ====
The editor that we use for designing of the PCBs is Eagle from www.cadsoft.de
It is a simple yet very powerfull PCB editor with backanotation between schematic and PCB.

=== Symbol definition ===

  -Supply pins have appended pin number after the name, for example VDD5 is a VDD pin #5
  -Pins are using orientation In, Out, I/O and Pwr-device is consuming power or Sup-device is power source
  -Pins that are active in 0 are prepended with /, for example /MCLR
  -Pins that have several seletable functions are named by one to three major functions, for example: IC1/INT1/RD0 with the primary function alligned to the edge of the package.
  
=== Package definition ===
  -generic packages are stored in SMT.lbr, to create manufacturer speciffic package, copy the package from SMT.lbr to manufacturer library and modify it there.
  -in package description write size of the package and pin pitch, e.g. 10x10mm pitch 0.5mm
  -Always verify that the package size and pitch matches the component package drawing in datasheet.
  -Verify that pin 1 of the package is marked on the PCB, the mark must be visible after component is soldered in place.

=== Device definition ===
  -In device description write brief description of the device and describe if there are naming conventions in the device naming, for example 103=10K 


===== PCB manufacturing parameters =====

Our standard 2 layer PCB parameters are:

  -2 layer PCB FR4
  -Minimum trace width/spacing 7/7 mils 
  -Via hole diameter 15 mils
  -components top side only

==== PCB manufacturing houses ====

  * PCB FabExpress www.pcbfabexpress.com
  * ZoomPCB  www.zoompcb.com
  * Cordova