XO1.75 EC Breadboard: Difference between revisions

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[[Image:XO1.75_EC_Breadboard_Top.jpg|thumb|220px|center]]
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Copper tape was used to supply +3.3V and ground. A sprinkling of 0.1 uF SMD-1206 caps provides decoupling between these.
Copper tape was used to supply +3.3V and ground. A sprinkling of 0.1 uF SMD-1206 caps provide decoupling between these.


[[Image:XO1.75_EC_Breadboard_Bottom.jpg|thumb|300px|center]]
[[Image:XO1.75_EC_Breadboard_Bottom.jpg|thumb|300px|center]]
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[[Image:XO1.75_EC_Breadboard_System.jpg|thumb|300px|right]]
[[Image:XO1.75_EC_Breadboard_System.jpg|thumb|300px|right]]

[[Category:XO-1.75]]
[[Category:Hardware]]
[[Category:EC]]

Latest revision as of 04:50, 13 October 2010

This page describes an engineering prototype used briefly during the bringup of the XO-1.75 design, in order to further software development of the Embedded controller and the XO-1.75 Host/EC communications protocol.

XO1.75 EC Breadboard Block.png

Documentation

The breadboard is powered by any XO power supply.

Construction

The heart of the breadboard is a ZIF socket for the 0.4 mm pin pitch 128 pin QFP package used by the KB3930. This is part number PA-QFE128SD-C-Z-02W, purchased from Ironwood Electronics. It includes an adapter PCB, and a wire-wrap adapter attached to that. This was mounted on a piece of 0.1" perfboard, onto which the required connectors and switches were epoxied.

XO1.75 EC Breadboard Top.jpg

Copper tape was used to supply +3.3V and ground. A sprinkling of 0.1 uF SMD-1206 caps provide decoupling between these.

XO1.75 EC Breadboard Bottom.jpg

Attaching to the Bonnell development board proved very difficult. I ended up tying to resistor and transistor pads, and a couple of test points, but had to epoxy over the wiring as the pads lifted off the PCB with the slightest force.

XO1.75 EC Breadboard System.jpg