29 May 2014: First revision routing

The Micro Desktop PC is a cut-down version of the Mini Desktop and the PCB size is around 4.5 x 3.0 in with USB, Ethernet and VGA connectors overhanging the edge of the PCB by about another 0.25in.

Connectors are arranged as follows: Top left is Ethernet, then downwards comes one dual-stacked USB2 connectors and the VGA port, followed by a a standard 5.5mm power jack (2.1mm centre pin), Bottom right is the reset switch and along the bottom edge is a 20-pin Expansion Header (1.27mm). All connectors are TOP side, with very few components underneath.

In essence this is a very simple board. RGB/TTL conversion to VGA has been kept to an absolute minimum by having buffer ICs straddle the EOMA68 RGB/TTL outputs within a few mm. All other high-speed signals are differential pairs. The design is nearly 100% complete: the 3.3v, 5.0v and USB power planes need to be done and it is ready to go.

Posted Thu May 29 17:28:46 2014