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confused how to hanle the power in the sch

Former Member

the way the eagle treat the poer supply and ground is confusing to me, i can not see the power pins on the breadborad even if i use the invoke command. how should i present the power if they do not appear on the screen ?

  • Hi,

     

    depending on the library definition the power pins (if there are any) can be in a separate symbol. If this is the case you have to use the INVOKE command for placing them in the schemaitc.  You write that the pins do not appear in the schematic. Could you give me some more details about this?

    What exactly are you doing? Which component do you click on?

     

    Regards,

    Richard

  • in reply to Richard_H

    Richard Hammerl wrote on Wed, 12 June 2013 05:03

    Hi,

     

    depending on the library definition the power pins (if there are any)

    can be in a separate symbol. If this is the case you have to use the

    INVOKE command for placing them in the schemaitc.  You write that the

    pins do not appear in the schematic. Could you give me some more

    details

    about this?

    What exactly are you doing? Which component do you click on?

     

     

    In EAGLE heterogenous devices (i.e. more than one gate aka symbol) can have

    power pins as a different symbol than the functional gates.  Use the INVOKE

    command to instantiate gates that are currently not displayed.  Type in

    "help invoke" into any command line to get more info about that command.

     

    However, any pin in a symbol that has the direction set to "PWR" will make

    an implicit connection to any other pin with direction set to "PWR" and

    having the same name.  This may have worked OK when everything in the world

    had VDD of 5V.  But in today's world this is dangerous and something you

    need to know about how EAGLE handles power pins.

     

    As an aside...

     

    Richard, please quote the context using proper NNTP etiquette.  Of all

    people, I expect that out of you, even if Element14 doesn't enforce it.

     

    Cheers,

     

    James.

    --

    James Morrison  ~~~  Stratford Digital

     

    Specializing in CadSoft EAGLE

    • Online Sales to North America

    • Electronic Design Services

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    --

    Web access to CadSoft support forums at www.eaglecentral.ca.  Where the CadSoft EAGLE community meets.

     

  • in reply to autodeskguest

    the device i am trying to realize is the simple 78XXL voltage regulator from the v-reg library. where i would like to supply the voltage for the rest of the componenets

  • in reply to Former Member

    Am 13.06.2013 19:44, schrieb mohammed alkindy:

    the device i am trying to realize is the simple 78XXL voltage regulator

    from the v-reg library. were i would like to supply the voltage for the

    rest of the componenets

     

    --

    To view any images and attachments in this post, visit:

    http://www.element14.com/community/message/79766#79766

     

     

    The 78xx "generates "power. So usually one gets a gnd symbol from the

    supply.lbr and connects that to the 78xx-gnd. Since these types of

    voltage regulators can have  different outputs, one takes a voltage

    symbol from the supply.lbr and connects that to the output of the 78xx

    (goes for the input as well) and so you have a supply power for your

    circuit image

     

    --

    Mit freundlichen Grüßen / With best regards

     

    Joern Paschedag

     

  • in reply to autodeskguest

    ok, that explains it, i will try that. all this time i was expecting to see these pins with supply pins ready to connect to produce voltages to the rest

     

     

    thank you Joern Paschedag