XO1.75 EC Breadboard: Difference between revisions

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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 [http://www.ironwoodelectronics.com/ 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.
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 [http://www.ironwoodelectronics.com/ 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.


[[Image:XO1.75_EC_Breadboard_Top.jpg|thumb|300px|center]]
[[Image:XO1.75_EC_Breadboard_Top.jpg|thumb|220px|center]]


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 provides decoupling between these.


[[Image:XO1.75_EC_Breadboard_Bottom.jpg|thumb|200px|center]]
[[Image:XO1.75_EC_Breadboard_Bottom.jpg|thumb|300px|center]]


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.
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.


[[Image:XO1.75_EC_Breadboard_System.jpg|thumb|200px|right]]
[[Image:XO1.75_EC_Breadboard_System.jpg|thumb|300px|right]]

Revision as of 04:37, 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 provides 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