Correct way to show 2 different power supplies on a schematic

Question

I am creating a schematic which is spanning multiple pages, and for clarity, the various ICs/components are being drawn with "+5v" & "Gnd" symbols.

However, due to current limit constraints I'm having to provide two separate 5v supplies.

What is the correct way to show this on a schematic though?

Should I just be adding extra labels to my +5v symbols to identify the source? Should I actually add in the two different power supplies and then use net names instead of the +5v symbols? Or is there another way?

Answer 1

For maximum clarity, you should write the schematic with the component and net names only, e.g. \$ V_{DD1} \$ and \$ V_{DD2} \$. This will prevent the readers from immediately mentally combining the two when they see the 5V supplies. Then, the application notes should include everything about supplies: current limits, voltages, etc. By the time the readers see that they are both 5V, they will know that they cannot be combined. Specifying this information on the schematic is also a possibility, but clutters up an already large schematic. I would only do that if it is essential to understanding the circuit.

According to this article, "Good schematics show you the circuit. Bad schematics make you decipher them." Putting only the 5V label on a supply or net is too ambiguous in this case, and would require some deciphering.

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Problematic:

^{simulate this circuit – Schematic created using CircuitLab}

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Acceptable:

^{simulate this circuit}

Note: I took a guess at the schematic configuration. If the voltage supplies actually share the same load, let me know and I will update the diagrams.

Answer 2

I would have no problems with +5VA, +5VB etc..