Author Topic: supply lines for LM324 in Eagle  (Read 7832 times)

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Offline joe61Topic starter

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supply lines for LM324 in Eagle
« on: October 09, 2011, 05:00:08 PM »
I've been looking around the net and haven't seen what I'm trying to find. Hoping someone here can point me in the right direction.

I'm trying to use an LM324 op-amp in a schematic, but the parts I see in Eagle don't have the supply lines with the schematic symbol. For example, see the attached schematic. When I do the board layout, how do I connect the supply lines with the op-amp?

Also, each op-amp I use in a schematic turns into a separate chip in the board layout.

If someone could point me to a web page I'd appreciate it. I'm hoping I haven't been missing something really obvious.

Thanks

Joe
« Last Edit: October 09, 2011, 05:02:46 PM by joe61 »

Offline waltr

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Re: supply lines for LM324 in Eagle
« Reply #1 on: October 09, 2011, 07:22:37 PM »
There is another part of the op-amp. Notice that the RefDes is IC1A, with the 'A' meaning part A of a multi-part schematic symbol. There will be an option when placing the schematic symbol for part A, B, etc. Then just ensure that the RefDes is the same for each sub-part, IC1A, IC1B, etc and it just part one physical part on the PCB.

Offline joe61Topic starter

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Re: supply lines for LM324 in Eagle
« Reply #2 on: October 09, 2011, 08:43:01 PM »
Ahh, I get it now. I made up the schematic for one of the IR sets, then just copied it to make the other. I deleted and re-added the op-amp and it's fine now.

Thanks, and sorry for the brain cramp.

Offline Soeren

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Re: supply lines for LM324 in Eagle
« Reply #3 on: October 11, 2011, 05:44:49 PM »
Hi,

I'm trying to use an LM324 op-amp in a schematic, but the parts I see in Eagle don't have the supply lines with the schematic symbol. For example, see the attached schematic. When I do the board layout, how do I connect the supply lines with the op-amp?
If you make an error check (menu: Tools->Erc) you'll see the net names of the power lines that aren't connected. For the LM324 they should be named V+ and V-
Quote
ERROR: Sheet 1/1: no SUPPLY for implicit POWER Pin IC2P V+
ERROR: Sheet 1/1: no SUPPLY for implicit POWER Pin IC2P V-

Then you have two options. Either use power symbols of the same name connected to your supply lines or just rename the nets to what's needed. Attaching a power symbol to a line will rename it for you. You can only have one name on a net, so you cannot call it V+ and Vcc, so if you're using an LM324 together with eg. a 4093 (which has Vdd as its positive power line), you have to cheat a bit (or change the library to show the power lines, so that you can connect them to any named net).


For clarity, I use the symbols on schematics that other people should be able to read, but when I want to make a quick PCB for a proto, I just change the net names.
Regards,
Søren

A rather fast and fairly heavy robot with quite large wheels needs what? A lot of power?
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