Apple SWIM Chip Adapters

alxlab

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Sep 23, 2021
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Apple SWIM Chip PLCC-28 to DIP-28 Adapter Apple SWIM Chip PLCC-44 to DIP-28 Adapter


Apple SWIM Chip Adapters

This project is for a couple of chip adapters to convert the PLCC-28 and PLCC-44 Apple SWIM chips to DIP-28.


The intention of the project was to allow me to use the PLCC-44 SWIM chip from my battery bombed Macintosh Classic in a Macintosh SE to give it 1.44MB floppy drive support.


The PLCC-28 and DIP-28 SWIM chips have the exact same pin layout (i.e., pin 1 goes to pin 1, pin 2 to pin 2, etc). This means that PLCC-28 to DIP-28 adapter can be used with universal programmers as well.


The pinouts of the SWIM chips was found in the SWIM_Chip_User's_Reference.


Bill of Materials

Apple SWIM Chip PLCC-28 to DIP-28 Adapter

Quantity​
DescriptionDesignatorsProduct NumberDatasheet
1​
Supercapacitor balancing IC.U2PLCC-28-ATpdf
28​
lead frameSHP-001pdf

Apple SWIM Chip PLCC-44 to DIP-28 Adapter

Quantity​
DescriptionDesignatorsProduct NumberDatasheet
1​
Supercapacitor balancing IC.U2PLCC-44-ATpdf
28​
lead frameSHP-001pdf

The lead frame/dip pins are hard to find in North America. If you live Japan you can find the here https://akizukidenshi.com/catalog/g/gC-14182/. Alternatively you could use normal square or round header pins at the risk of damaging the socket.


Manufacturing

The release includes the manufacturing files for JLCPCB specifically. If you need to the gerber files, BOM or component pick & place in a different format then you would have to generate them yourself.


The PCB thickness chosen should be 1.6mm.


License

Creative Commons License


Macintosh Portable Battery Adapter by Alexandre Marcoux licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
 

Kai Robinson

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Sep 2, 2021
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There's one more that could be made - a PLCC 44 pinout to PLCC-28 through hole socket layout - for Mac II's that shipped with an IWM, cause there was a PLCC-28 SWIM available for them in an upgrade kit that was used almost no one else.
 
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