Altium Flat Vs Hierarchical Design - Page 1
Forum section: electronics / general

author: 2X
author_rank: Frequent Contributor
timestamp: August 24, 2025, 08:48:38 pm
content: Hello,could you tell me your opinion if hierarchical design is not easy readable in compare to flat design. I always use flat design (4 pages max I have done until now) and I would like to use the hierarchical design from now on. I read on some comments no the youtebe that hierarchical design is not so easy to read from a third person... what is your opinion?Until now I have undertand the below(please correct me if am I wrong):Hierarchical DesignPros:If you have a repetable design/schematic you can create clones (multi-channel schematic) of this one schematic instead of creating copies of the same sheet/schematic file.You can use a schematic to another project.Hierarchical Design Cons:Time consuming.TIP #074: If it’s not necessary, you may not want to use a hierarchical schematic designAltium Schematics #01: Hierarchical schematics designAltium Designer Tutorials - Use ports to make old schematics re-usableHow to Create Schematic Channels | Multichannel Schematic Capture

author: ajb
author_rank: Super Contributor
timestamp: August 25, 2025, 04:13:13 pm
content: It shouldn't be that hard to trace signals through a well-designed hierarchical schematic. To be fair, I have seen some examples that broke the design down into an excessive number of sheets, which were hard to read for that reason. The key thing with hierarchical designs is that they work best when each sheet symbol is logically contained, so that relatively few signals (or groups of signals, eg bus or harness) are required to connect them.It does take a bit of extra work to manage connections through multiple layers, and I do wish that were better in Altium. But that's really only an issue at the beginning of the project, and if you pay attention to the errors Altium reports it's not a big deal. Also harnesses make everything easier -- for example, running SPI between sheet symbols can be done with a single port/sheet entry using a harness rather than separate ports for SCK/DI/DO/CS, which also makes everything a lot tidier.

author: free_electron
author_rank: Super Contributor
timestamp: August 25, 2025, 06:13:24 pm
content: Use strict hierarchical. and turn on the function to display page cross references.

author: 2X
author_rank: Frequent Contributor
timestamp: August 25, 2025, 10:08:58 pm
content: Hi, I made a try to create a Hierarchical Design but I am totally confused of what names I have to give to the ports.1. The ports from different sheets can have the same names?2. How to connect the sheet symbols between them... with wires or with labels?3. In my ports on the left or on the right shows me an annotation "Main 2B" or "Main 2C" (picture 4) . What is this... I didn't see this annotation on other ports on a Hierarchical Design?I have upload my project if a guy can take a llok and tell me a prefered way about port names and sheet symbols wiring.P.S. The red circles where are placed in some nets are test points and not labels or power ports.

author: thm_w
author_rank: Super Contributor
timestamp: August 26, 2025, 12:40:13 am
content: Main is the other sheet its connecting to, 2B is the location on the sheet (2 is the X location, B is the Y location, look at the margins):https://www.altium.com/documentation/altium-designer/schematic/multi-sheet-hierarchical-designs#adding-cross-referencesDid you watch the tutorial videos you linked and read some of the altium documentation?https://www.altium.com/documentation/altium-designer/schematic/multi-sheet-hierarchical-designs?srsltid=AfmBOorqS3GmIXm_vDaxVMwIqXNr5E0w9im6JZQz3I7wzELCe7ElukoO#hierarchical-design

author: nctnico
author_rank: Super Contributor
timestamp: August 26, 2025, 10:00:19 am
content: Quote from: 2X on August 24, 2025, 08:48:38 pmAnd you forgot another important downside: signal names tend to change when using hierarchical blocks because people are inconsistent. This makes it extremely hard to review a schematic and/or use a schematic for bringing up & debugging hardware. On one page the signal of interest is called Peter, on the next page it is called Suzanne which makes it hard to trace a signal. In my experience, using hierarchical blocks is very prone to introducing errors which go unnoticed.Personally I only use hierarchical blocks when I need to re-use the same circuit more than 4 times.The example schematic you posted above is horrible. Just put such a simple design in one schematic. The person who is going to debug this circuit is going to thank your for that. In software I see similar behaviour. What could have been in one source file suddenly gets spread over three files due to some urge to classify things as much as possible. However, the end result is that none of the three source files make sense. It is an incoherent mess. Think about cutting a puzzle into pieces which are so small that you lose the ability to see where they belong in the big picture.When designing schematics keep in mind that a schematic should represent a logical flow of signals with the inputs at the left and the outputs at the right. As a rule of thumb don't make pages bigger than A3 paper size. That can still be printed readable on A4 or letter sized pages (if you change the Times font to Arial in Altium).

author: 2X
author_rank: Frequent Contributor
timestamp: August 26, 2025, 07:06:41 pm
content: Quote from: thm_w on August 26, 2025, 12:40:13 amI read this:https://www.altium.com/documentation/altium-designer/schematic/multi-sheet-hierarchical-designs?srsltid=AfmBOorqS3GmIXm_vDaxVMwIqXNr5E0w9im6JZQz3I7wzELCe7ElukoO#hierarchical-designI haven't read this:https://www.altium.com/documentation/altium-designer/schematic/multi-sheet-hierarchical-designs#adding-cross-referencesBut still I am confused. Could you tell me with what names you will annotate the ports (in each sheet symbol you will give a different names.. for instance in one power supply sheet you will have "+3.3V" and MCU sheet you will have ""MCUVCC" instead of "+3.3V"? Could any guy give me an example?Thanks for your reply.

author: 2X
author_rank: Frequent Contributor
timestamp: August 26, 2025, 07:10:36 pm
content: Quote from: nctnico on August 26, 2025, 10:00:19 amI don't have experience with hierarchical design but I am afraid I agree with you. Anyway I would like to give a try to see in practice this technique.Thanks for your reply.

author: thm_w
author_rank: Super Contributor
timestamp: August 26, 2025, 11:04:45 pm
content: Quote from: 2X on August 26, 2025, 07:06:41 pmAs nctnico says, if you give everything different names (3.3V, and MCUVCC) it can get confusing.You can name them both +3.3V if you want, assuming its designed around that voltage. Or one can be MCU_3V3.