Drawing Schematic in Eagle

[Haberdasher]

I've started fiddling around with this.  It all seems fairly straightforward, but I am stumped on how to split up a single IC and designate the 2 halves as IC1A and IC1B, each with 3 or 4 pins, while making eagle understand it is the same IC.  If I can't figure out how to do this it's going to get messy really fast.  And yes, I googled first. 

help?

[jkokura]

Ics do it automatically in eagle when you use the right part (like a TL072). What library are you using?

Jacob

[Haberdasher]

gaussmarkov's.

I wanted to use a LM833- which I couldn't find in there, so I just grabbed a different one- a LM386.  Should I have done something different?

thanks, jacob.

[jkokura]

What kind of op amp is a lm833?

Try using a TL072 if it's a dual op amp.

Jacob

[Haberdasher]

lol I'm a dumbace, the LM386 must not be dual.  For some reason I thought these were equivalents.  Thinking about too many things at once, I guess.

thanks for the nudge in the right direction.

[madbean]

You can use any generic dual and just re-name it later. I usually just plug in a TL072 and then name it to whatever it should be.

Also, make sure that you use the "invoke" command to get the supply and ground pins. When you do that, it will bring up the drawing which you can place anywhere on your schematic. You can connect this to either of the amps or you can connect it to your 9v supply portion on your schem (I prefer this).

[Haberdasher]

Thanks, guys.
Do I use wires or nets when connecting components?

[jkokura]

Nets

[madbean]

Nets will also automatically create junction points (dots) when two or more are connected together.

[Haberdasher]

bean- what size copper/dimensions and drill holes do you recommend in the design rules?  I downloaded some dude's .dru file to use, but his traces and holes aren't as beefy as yours.  I'm not precise enough with my cheapo drill press to nail all those tiny little marks so I'd like to go bigger.

Also, I can't figure out how to do the big black ground pour around everything?  I followed a tutorial where I drew a polygon around the perimeter and named it GND, but it didn't do what I thought it would.  I guess it's not necessary, but it would cut down on the etchant.

thanks

[madbean]

The pad diameters and drills I use have been re-sized in each individual library. There's a quicker way to do it, though. Here's some stuff cobbled from posts I've made on FSB:

http://www.freestompboxes.org/viewtopic.php?p=56625#p56625
When your layout is done, use restring to size all the pads up to a min of 22 and max 26. If you've done all the above you will have a really nice pad/trace size to work with, and no overlap. If you find some pads and traces are overlapping, see if you can readjust the placement of the component. If it becomes too much hassle, just restring again with a smaller min/max.


For the ground pour, here's a little illustration.



[attachment deleted by admin]

[Haberdasher]

Thanks for linking that thread, I picked up a bunch of things from that already- like changing the grid in layout mode.
One thing I didn't pick up on is- Do you change the grid to 25 mils with a 4 multiplier in schematic mode when you draw it out, too?  It seems like I remember reading that you should use the same grid in both or the nets have a hard time matching up with the components...

[madbean]

In schematic mode I use 50mil with a 2x multiplier. I don't think there is any correlation b/w grid sizes in schematic and layout mode...at least with these settings I've never noticed.

[Haberdasher]

Well, I think I've made some progress here.  The problem I'm having now is after pouring ground, the space between the ground and my nets is too slight.  I've jacked with this for hours and I can't seem to figure out which parameter to adjust to increase the size of those dern thangs.  Just to be clear- I'm talking about what will end up being non copper, post-etch.

gracias

edit: nevermind, figured it out.