FEDEVEL
Platform forum

Kalaslas , 08-29-2025, 12:29 PM

Up until now I've handled generic components (SMD ceramic resistors and caps) in Altium by having one library component for each size (so 0402 Resistor, 0402 Capacitor, 0603 Resistor, and so on), and when I place the component in my schematic I specify value, voltage rating, tolerance, and any other parameters needed.

Now we are moving over to a different EMS however, and this EMS prefers that I change how our BOMs look. They want all generic components to have a "Description" field in the BOM that follows a certain naming convention, where resistors for example look like this:

Res 15k1 1% 0.125W 0805
Res 2R2 5% 0.25W 1206

I don't want to have to create a library component for each individual resistor and capacitor value, so I'm looking into some neat way of having a generic component where the "Description" field can be autogenerated.

So I'm playing around with Altiums standard way of using generic components, where I can set a Default Value for the "Description" field in the Resistor template. My question is though, how can I set the Default Value of the "Description" field to include other fields? I'm specifically trying to get the "Description" to be "Res + 'Value' + 'Tolerance' + 'Power' + 'Footprint'". Is this possible even?

Robert Feranec , 08-31-2025, 03:04 AM

Your EMS suggestion is correct ... you should have a component library that includes each individual resistor. If you are going to change your system, I highly recommend you to do it the way as your EMS is suggesting. It may look like a lot of work, but it is not s lot of work and it will save you a lot of time in future and it prevents mistakes.

There are more ways how this can be done e.g. if you are using Altium libraries or database libraries, then basically you only create resistor symbol once, you create specific footprint once and then you create the specific component e.g. resistor Samsung 1k 0402 1% PN: XXXXXXXX and link the symbol and footprint to it.

If you are using file libraries, then you can import parameters of the component e.g. from digikey, copy and paste symbol from an existing resistor and assign existing footprint.

Robert Feranec , 08-31-2025, 03:06 AM

You may spend some time trying to build a new system based on your idea, but sooner or later you will need to move to the system with individual altium components for each real component.

Kalaslas , 08-31-2025, 08:40 AM

Why though? To me that just seems like building an unnecessarily large library that then needs to be maintained?

Robert Feranec , 08-31-2025, 12:26 PM

This will help: https://youtu.be/fRaPwBUokJQ

QDrives , 08-31-2025, 07:11 PM

Because every resistor also has unique:
- MPN
- Value
- Marking
- Supplier data
- Product page (sometimes)
Even when picking them from the same manufacturer, family, size, etc.