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Selecting packages by "standard" names?

Avatar Posted by PeterPan at

OK go easy on me guys, I don't design circuits that frequently. I'm a former user of Circuitmaker/traxmaker and I d/ld Desitgnspark today in hopes of something better. One of the things that used to drive me crazy was finding the right package for parts. I have only very recently come into the SMD world, and still have often stuck with through hole technology because of this very hassle. With a through hole part all you need is to recognize the footprint by eye, from just a few choices, and maybe tweak the hole sizes sometimes. But with SMT, there are different package patterns that seem to have become industry standards, and yet my Circuitmaker didn't use a single one of them. So I'd end up designing my own footprints all the time. To add insult to injury, I'd often find out later that the part footprint I needed already existed, but had some screwy name that I'd have only found by guessing. For instance, I often use size 805 for resistors and capacitors (because if they are smaller, I can barly see 'em!). But I'd never find any part like that in the library... it would be hidden with a name like "RC4" (???). Similarly, I'd decide to bite the bullet and use an SMD version of an LF353 OP amp I'm used to designing with. OK, the TI manufacturers data shows a nice picture of an SMT version of that chip, and says it's NS Package Number M08A. Well that's nice, but no designator like that in my Traxmaker, so I'd be off designing another footprint. This one task, finding (and often designing) the correct footpring for parts is one of my biggest time gluts, and a major reason I often threw in the towel and went back to through hole designs.  

 

Now please tell me that Designspark is better. I can see that the library is vast compared to what I had in that Circuitmaker program, so there's probably a much better chance I won't have to design every package. But I'm trying to go through the tutorials and design some simple circuits, and when its time to pick a package I feel just as lost as ever. If I want an 805 resistor, do I pick RA-SM and hope for the best? What about that LF353? Well I'm really glad to see I can enter the part name have 1/2 dozen choices that are SMD and look like they might work. But again not one of the ones listed matches the "MO8A"  in my TI book. please tell me I'm just a newbie that doesn't know where the marbles are hidden. 

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    Posted by MikeBK at

    Hi PeterPan,

    You will find DSPCB easier to use and more powerful than Circuitmaker.

    To find 0805 package go to libraries (CTRL+L), select 'PCB symbols' tab, select 'sm.pls' library which is a standard surface mount library, the 0805 package is right at the top of the list.

    It takes some time to find your way around libraries but there is plenty of components and you can reuse footprints to create yout own libraries.

  • Avatar

    Posted by PeterPan at

    .

  • Avatar

    Posted by PeterPan at

    Yes... its starting to make sense now.:-)

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