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Electronics => PCB/EDA/CAD => Altium Designer => Topic started by: Harvs on January 20, 2017, 11:15:15 pm

Title: Schematic Sheet interconnect
Post by: Harvs on January 20, 2017, 11:15:15 pm
I'm trying to understand the best way of doing a multi-sheet design as it gets quite large.

From my understanding, there's two ways in Altium; Flat or Hierarchical.

Reading online it seems everyone is saying that Hierarchical is the only way to go, and indeed from what I've done I don't believe you can do Repeat symbols without it (at least it didn't work for me.)

But then I look at the Fedevel OpenRex board, and it's clearly a flat design.

While I can see the virtues of a Hierarchical approach, the actual sheet symbol interconnect seems to get very complicated when you have say 10+ sheets with each sheet connecting to more than one other sheet.  Or am I missing something...
Title: Re: Schematic Sheet interconnect
Post by: T3sl4co1l on January 21, 2017, 01:35:37 am
Flat is perfectly fine when you're not repeating sheets, and the interconnection is more general than tree-like.

In a flat design, you can use Port symbols, or use Off-Sheet Connectors.  Wires named with the same Net Label will also be connected, but you should try to avoid that because it leads down the slippery slope of graphical netlisting*.

*I don't know if anyone calls it this, but consider: a netlist is a plain-text representation, naming every pin of every component, and which nets those pins go to.  Utterly useless for seeing how a design is connected up.  Now consider a schematic design, where components are placed wherever, and each pin has a net name on it, no wires needed...

Tim
Title: Re: Schematic Sheet interconnect
Post by: Harvs on January 21, 2017, 03:39:12 am
Flat has certainly worked for me with a large design recently, however is there a way to repeat sheets with a flat design?  Or does that mean you have to go Hierarchical?
Title: Re: Schematic Sheet interconnect
Post by: Someone on January 21, 2017, 07:36:27 am
*I don't know if anyone calls it this, but consider: a netlist is a plain-text representation, naming every pin of every component, and which nets those pins go to.  Utterly useless for seeing how a design is connected up.  Now consider a schematic design, where components are placed wherever, and each pin has a net name on it, no wires needed...
You'd think that would never happen and then...
https://www.eevblog.com/forum/projects/overcomplicated-audiophool-dac-design-review/?all (https://www.eevblog.com/forum/projects/overcomplicated-audiophool-dac-design-review/?all)