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    Friday, January 28, 2011

    Orcad vs Eagle: Yet Another Comparison.

    Introduction

    I read a lot of articles online with regards to Board design Software and two names kept popping up: "Cadence Orcad" and "Cadsoft Eagle". I have been an avid user of Orcad since 2005 and have learned to use it more professionally and accurately with the years. I have also invested a lot of time in building custom libraries for Part footprints etc so I was initially biased in favor of it. Then a couple of months back, I started doing a lot of Open-Source Projects and began exploring the "Open Source" ways of Life so to speak. Needless to say the Orcad fit nowhere in the scheme of things. Cadsoft eagle however was a name that popped up a lot which is attributed to two reasons... ONE: There is a Lite -FREE version of the tool available and the professional version is not as costly as Cadence Orcad. TWO: Because of the Lite Version, there is a lot of people doing work on this so as far as open source projects are concerned, if you want to put up a project schematic and board up without getting in a legal mess, Eagle is the best way to go.


    A few years back, most of the companies did NOT provide footprints for their devices in anything other than OrCad but now things are looking up. Since there is an open source community backing up projects in support so a lot of new device footprints are designed and distributed by users and online vendors, free of cost. Why? Because it makes sense to tell users how to hook up the components they sell.

    I am quite familiar with Orcad's features so I decided to get my hands dirty with Eagle so as to produce a valid comparison. I don't use spectra router in Orcad and really don't go beyond 4layer boards. For prototyping I am still working with 2 Layer boards so the Lite version was really OK.


    I wanted to get a feel of how both tools were different so I did a complete flow in both the tools


    Orcad

    I followed my regular work flow where I added the components to the schematic- Multiple pages for my schematic etc. Then the Placement groups and associated footprints per component. verified that the schematic was in order and all the footprints were the right ones. I have a bad experience with a footprint one of my team guys botched up. For a DB9 Male he choose female- so whats the big deal with male and female footprints- they look the same anyways. The problem is that they are a mirror image of one another so I get pic 4 where I should get pin 2. Once done I did my DRC and then generated the netlist.


    Then I go to my Layout editor- create a new board, create an outline, place group by group etc. Next select the Layers to be routed, track widths and spacing. Start smart route, verify auto-route settings and route.


    Next go back to Layout and then do the Mounting holes, do the copper pours and then generate the Post scripts and done... wow thats a lot of work but very nicely done.


    Eagle

    Since I had just read the basic user manual and tutorials from a couple of websites etc so may not be familiar with a lot of the advanced options but here i go...


    The first thing I liked was that the component library not only shows me the symbol but also the footprint which is very good in my view. I placed all the needed components on my single page(LITE version restriction) and this was very similar to the capture tool for orcad. The only difference was that some tools were easy to use in capture like wires, buses, netlists, etc. I am comparing v10.x of orcad here. But anyways eagle impresses cause I don't have to verify footprints- its done when I select from library. Next I run the DRC and done. To get my board up I simply click on the board option in the tool bar. No need to expert netlists etc. This feature will KILL usability where the schematic is made by a different person and boards are done by different people. For single user projects no problem though but for large size teams BAD BAD BAD.


    Next the layout no option for groups but instead simple select the schematic symbols and BAM you get the components highlighted in the board editor. Really cool feature for small scale developers. Placement is easy and the rest I just followed the manual on selecting the layers etc.


    One tool worth mentioning was the Rat's nest tool- I don't recall capture having anything like it and it really helps for certain things- again on a small scale.


    Creating the PS was a piece of cake as compared to Orcad- I had made a preferences file for it so just loaded it into the CAM tool and hit Process... DONE.


    Conclusion

    Did I like Eagle? YES


    Is it Better? NO


    Is Orcad Better? Uhhhh...


    Orcad is a good tool for large teams and corporate setups. Allegro set of tools allows you do SO much more than eagle. But if you are working alone(board wise) and are on a budget then eagle is better.


    Eagle is a simplified schematic and board design tool for hobbyist and small scale developers and is recommended for you if you are looking for a solution that is NOT for big projects that may need experienced people teams.



    UpdateThe reason to use a Cad Tool for PCB design is the ease with which a circuit can be routed into a board. I tried routing a more complex board with Eagle and I have to say that the routing algorithm was written by an 8 year old with no coding experience... Thats right, the autorouter is completely and totally brain dead. Watching the autorouter is like watching a Blind Mouse run around in a 3D maze- entertaining at first but totally Pathetic. Some might thing I just dont know how to use the tool but there are a lot of people that share my view. If I was creating breakout boards, then the tool will do. If I want to route it myself, then its usable but for all practical projects, its useless. Back to Orcad for me.

    8 comments:

    1. Thanks for sharing your experience

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    2. Here it is March of 2013. Having used Cadsoft Eagle for nearly 2 years and having grown accustomed to it my company recently updated it's license, only to find a price increase. I just did a price check. a single user license for Cadsoft Eagle is $1540 US for a comparable license for OrCad is $1670 US. Which effectively levels the playing field between Eagle and OrCad.

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    3. There are subtle differences between the two and the purchase decision is also depended on the trained staff available for for the tool. I'm in the process of writing an update to the review since the routing in eagle has changed a bit. But good of cadence to lower the cost however I'm not sure if smart route is part of that package.
      Cheers

      ReplyDelete
    4. Hobbiers could look info fritzing.
      The autoroute is horrible and there is no check on electronics. But it's free. And open source.
      It also has a breadboard view, just to show how hobby it is I guess.

      ReplyDelete
    5. If you are looking for an Open Source tool, try KiCAD.

      ReplyDelete
    6. I already have and will be doing a review shortly. Thanks

      ReplyDelete