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Using generic components during schematic in Altium designer

gyuunyuu1989 , 07-13-2023, 07:23 AM
I am trying to find how to get generic components into Altium designer. Basically with generic components we shall have generic resistors, capacitors, inductors, diodes e.t.c with popular footprints like 0402, through hole e.t.c. These are generic in the sense that they are placeholders and not tied to a specific part from a manufacturer. We can complete the design with these and when we know what exact components we shall use, we can replace the generic components with the real components.

In my Altium designer, I can see there is a "Simulation Generic Components" but these do not seem to have a footprint if I go by the parameters. It seems that these are for use in simulation and not in schematic capture. I do not see any library that has the word "generic" in its name.

How do I bring generic components with footprints into Altium so that I can create schematic without knowing the exact part that shall be used at time of schematic creation and then I could do the PCB layout as well (possibly). Once I know what specific component to use, I can just replace the generic part in the schematic with the real part from a vendor with manufacturer code. I am sure such a feature exists in Altium but it is not clear how it is enabled.
qdrives , 07-13-2023, 03:16 PM
Starting blank it can be interesting to say I need to 13k3 1% resistor, max 10mW. For the layout you pick a 0402 one.
You finish the schematic, do the layout. No you need to order.
When will you add more detail?
Do you let the manufacturer pick any 0402 13k3 1% resistor?
How about the capacitors? Inductors? Diodes?

Diode package? It is not like resistors where the size is either driven by power or voltage.
For the capacitors -- what about temperature? DC bias? AC bias? Tolerance?

For these 'simple' components it might still work, but would you do the same for the buck regulator and the microcontroller?
If not, then why do it for the other components?

If you fill in the details at the end and put it in your library. For your next design, will you again start with the generic component or pick the already detailed one?
If you then use the detailed one, then why not put in the detail to begin with?

What details do you put in the library?

You are not the first to go through this process:
I saw in a course by Mr Robert that he creates ALL components in the schematic library each time, can't I just reuse components I've previously created? and is it bad to just place the component and modify it's parameters in the schematic itself, instead of creating a new one?to explain it better, for example, Instead of

When coming to components like LEDs, resistors, capacitors e.t.c there are throngs of manufacturers and suppliers that provide parts that are very similar from PCB design perspective i.e the schematic symbol and footprint. What approach then does one take when designing parts libraries?Lets take an example, lets say I have a

My recommendation is to create a detailed symbol for each component you need before you place it on the schematic.
You also make/assign the footprint at that time to prevent the situation that there is an unknown element when you start with the layout and it may push you to select another component.
WhoKnewKnows , 07-13-2023, 04:03 PM
There are some FOSS style group maintained db type libraries around. If one starts with that, could be easier to get going from scratch
gyuunyuu1989 , 07-13-2023, 05:43 PM
Sometimes we might not know if we need 1% tolerance component or 10%. We might realize that we need capacitor of specific material e.t.c. We place details later as the design process proceeds. In other words, the first attempt at schematic is uses generic parts. As we progress in the design process, we are able to specify more specific details and eventually specify an exact part number. I am not a professional PCB designer (yet) and am learning this skill and so I have no idea how professionals actually do this.
qdrives , 07-14-2023, 01:31 PM
So you start your design and select the 10% tolerance resistor (for argument sake, lets assume you can buy one, there is plenty of stock and is the cheapest).
Further into your design you realize that it actually needs to be 1%. Now what? Two choices:
1) You modify your existing one in the library and update the schematics it is used in.
2) You create a new component, because the 10% is a lot cheaper and you still want to use it in the other places.

"Sometimes we might not know if..." -- there is plenty of thing you do not know, especially when you are a beginner. That is not a problem. However, There are many thing where is it wise to do think about it much sooner. Then again, if you learn that it needs to change, see the the previous 2 choices.

If you say "I am just a (schematic) engineer", you may find that a lot of details in the library are not important and not your job to fill it. I work in companies where I also do the layout, support production and incoming goods inspection, and repairs. All these require different sets of data. That data needs to be in your library if you want to work efficient.

Besides, changing or copying the component from 10% to 1% or 10k to 13.3k takes less then 1 minute. However, coming to the conclusion that you need 1% easily takes hours.
robertferanec , 07-23-2023, 04:22 PM
Simply use 1% everywhere and only optimize the cost when you go to very high volume production. How much do you save by using 10%?

PS: don't forget, your company doesn't need to stock both, it also helps a lot. That is why we rarely use 10%
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