Hello, I’m trying to use an op275 IC in the schematic layout. When I add the I see that it is split into “unit A”, “unit B”, “unit C”. I’m a new user of kicad and eda software in general, so this is a little confusing to me. How does one lay out the schematic so that everything will connect correctly? When I look at other people’s schematics, I see an op-amp symbol graphically connected to a V+ and V- symbol, which makes sense to me. The various units of the kicad symbols are not connected. Do I just stick them anywhere, and it works out? What if I add several op275’s? How are the various units associated?
OP275 is a dual opamp package (or appears to be from the symbols provided, I haven’t bothered to look at a datasheet). Unit A is one opamp, unit B is the other opamp, and unit C are the power pins. This allows you to use the opamp symbols on your schematic where they make sense to be used instead of artificially smashing two sub-circuits together confusing their independent functionality. (Remember schematics are to communicate your circuit function, not the circuit layout.)
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That makes sense. What about my last question? If I add several of them, will naming them U1A, U1B, U1C, U2A, and so on tie them together when it comes time to make a PCB?
KiCad automatically uses the correct footprint pads. You have to be careful that, as in your post above, that if you allocate a U2A, that you also have a U2C and it is good practice to put the U2B on a sheet of unused units.
In the case of logic ICs, the unused units still need their inputs to be ties to a power supply. KiCad will not do this automatically for you.
Perfect. I understand exactly what you’re saying. Thanks for the fast help everyone!
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