Eagle Library: Gadgeteer socket?

While I like the extended exposed copper of the footprint (I should, I use it myself :slight_smile: ) it does cut down on the available space and extends the space you need around the footprint to route things, and you might need a bit more space than ā€œusualā€, and once you get used to soldering the things (or progress to skillet/toaster reflow) you can go back to the easy to use one :slight_smile:

All things considered, your board is pretty damn good ! The only thing Iā€™d say is make sure you solder the 7-seg display on LAST otherwise youā€™ll never get to the socket :slight_smile:

1 Like

@ mhectorgato - Very good board! Especially for the first try.

[quote=ā€œBrettā€]The only thing Iā€™d say is make sure you solder the 7-seg display on LAST otherwise youā€™ll never get to the socket :slight_smile:
[/quote]

That was my plan:
1 - resistors and cap
2 - socket
3 - ICs
4 - 7-seg

Btw - how does the socket handle the heat of a skillet/oven? With it being plastic.

Handles just fine.

Thanks - there were several permutations, research and help to get to this point. I simplified the plan, but that leaves room for future features :wink:

Justin helped. Downloading GHIā€™s and various other vendorā€™s Eagle files helped. Google searches helped.

My first thought was a reflow station ā€¦ but a sheet of aluminum might be my first attempt. KISS

Yeah, I have 7 segment module as well. Mine smaller though than Justinā€™s . I have used surface mount version of the 7 segment.

My only question was on the resistor values.

Not really sure how to calculate them.

Based on this site: ME Labs, Inc. | 1-719-520-5323 |

So Iā€™m using the 5v pin and the LEDs are 20mA

3/.02 = 150

But Iā€™m not sure if/how the Darlington effects this.

The darlington wonā€™t affect it. Itā€™s simply a way to drive higher currents from a small signal input. Your LEDā€™s are way lower than the current it can drive. Your 150

One thing I would point out is to have 1 decoupling CAP per IC.

Also check your track widths on the power and ground lines. These really need to be much heavier. Their size should be based on the current capacity but for you little design, I would go with a 1mm (40mils) track width.

Not sure how to drive Eagle, but if you need to have VIAā€™s on the power tracks, set the software to use larger than the ones used for the other tracks. I usually make the via the same outer diameter as the power track and the holes half this. I am sure others will have a view on this.

As your board only has the 1 SMD you can just hand solder this. :slight_smile: I wouldnā€™t go to the expense and hassle of an oven for 1 connector.

1 Like

@ Dave McLaughlin - thanks for the info - helpful!

Dave - Just looked over my schematic again - Iā€™ve got a decoupling on my shift register. Not sure where I would add one on my ULN2803.

Were you referring to the 7-segment (as itā€™s common anode)?

Ah yes, I forgot it was a ULN20803 so not required. Sorry for the confusion. I only saw the footprint and should have put 2 and 2 together.

Gotcha ā€¦ does putting one on the anode of the 7-segment accomplish anything other than increasing my BOM?