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Questions relating to designing PCBs
By RossWaddell
#151998
I realize this is a bit of a noobie question, but what part # should I use for a standard axial 1/8w resistor? The dimensions from DigiKey's website state "0.067" Dia x 0.130" L (1.70mm x 3.30mm)" for the 150ohm resistor in series with a 2V LED. In my circuit, I'm using one from rcl > r_us > 0204V but I'm not sure if this is the right one. I tried searching for *1/8W* but no luck.
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By Ross Robotics
#152000
Have you looked at the package preview window? It tells you what the silk will look like with that part. On the bottom of that window, it has a ruler. You can determine how big the silkscreen is going to be.

With the 0204V, Have you noticed there is no space for the body of the resistor? Also, Have you seen how small the silkscreen is? It is because that particular part has the resistor mounted vertically. Hence, the "V" on the number.

You need the "0204/5" part. the 3.30mm is the body of the resistor. You will notice that on the preview window that the square inside the 2 pads/holes are larger than the 2mm on the ruler. You can guesstimate that the 0204/5 part would be the best option.

I also see everyone saying "Why don't you make your own part..." Well, Eagle has thousands of libraries so you shouldn't have to. The only time you may need to is if the part is not very common. Some of the newer ICs are not in Eagle yet. I had to build one part, and that was a new SMD part from TI. sometimes you do not want to make a part in Eagle, so Goggle the part name and add the word "Eagle" in the search. 75% of the time, other people have made the part and put it up for everyone to get. I've got many parts like this. Eagle has been gracious enough to even host a download page for those uncommon parts. http://www.cadsoftusa.com/downloads/lib ... anguage=en