3 Dec 2014: Revision 3.1 PCB

After the Revision 2.1 EOMA68-A20 prototypes were successful and the Micro-Desktop as well it was time to return to the Tablet PCB. A Micro-SD Card slot has been added as a direct connection to the EOMA68 interface. Significant layout improvements have been made over the Revision 3.0 PCB layout, including the discovery that the Texas Instruments SN75LVDS83B could be turned around 180 degrees and the pinouts with the RGB/TTL interface of EOMA68 lined up perfectly! Also by accident a pin-compatible china sourced LVDS IC has been found. The image below shows the component layout and the top layer. All components are still top-side: there is hardly any free space anywhere on the board, with the CPU Card and the Amphenol PCMCIA connector taking up the centre. Several corrections were made to the Silkscreen: it had not been previously noticed that there were overlaps onto component SMT pads! Iteratively printing out the gerber files and examining them with an external tool clearly showed where the errors were in ways that are not intuitively obvious to replicate from PADS 9.3