Hidden pins on NE5532

Hi,
I am using the symbol for NE5532 but the hidden pins don’t appear when I use the Icon, also the ERC dosent pick it up, I also was laying out the PCB and didn’t get any errors, on the schematic I had placed +VCC and -VCC, is this just a case of the symbol is incorrect or am I using the hidden pins incorrectly please ? first time I tried this and in principal it seems a reasonable idea, however most people seem to regard them as a pain in the bum. Can you clear this up for me ?
Andy

Cheers.

The stock NE5532 symbol doesn’t have hidden pins. It’s composed of 3 units. Did you add and connect unit C (the power pins)?

No I didn’t ! thanks, I didn’t know about this, but now I do, seems odd to me, but we live and learn. I would just prefer pins 4 and 8 to shown, I wont do that again !

Andy

Cheers.

I don’t understand the confusion. They are shown. And I wouldn’t say that unit C is any harder to discover than unit B. You can even nicely stack the power pins with one of the opamp symbols if that’s what you prefer (although you have to figure out what to do with the extra designator and value (hide them)). You’d better get used to separate power pins, as this is the preferred way of doing things in the official library (https://klc.kicad.org/symbol/s3/s3.8/).

If you want to see what symbols with actual hidden pins look like (just to familiarise yourself), take a look at one of the 74AHC1G* symbols. They are left over from the bad old days when hidden pins were still used. Take a good look at the symbol preview window and maybe enable the display of hidden pins to see them on a placed symbol. Those symbols are a single unit and have hidden pins, but other parts with multiple units and hidden pins exist too.

I’m just used to the symbol showing all the pins on the device, to be honest, most of the time I’ve made my own symbols (its so quick) and never thought about hiding them, I just add power pins and wouldn’t make them a separate unit, but seen you link about multi devices now and will adopt this, it makes sense, I get it now, and its a dual opamp and you have A and B but never thought about C being power, and will be careful, I certainly wont do it again !
Cheers
Andy

Having the power unit is safer than showing the power pins on “A” and “B”. If only “A”, why that one and if on both it is easy to make a mistake and connect to two different power supplies

I like to put the power unit in a corner of a sheet or grouped with others on a dedicated page. Then I can show associated decoupling easily

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Agreed, that makes sense;
cheers.
Andy