In general I prefer systems which can support the "one to many" approach where a symbol can map to multiple footprints. These systems are typically supported by a database.

 

For symbols which incorporate the pin number mapping I use this convention:

 

[Prefix]_[item]_[Variant]

 

For an IC the prefix would be IC and the item would be the manufacturers part number with RoHS and packaging codes removed.

 

For other parts such as Transistors the prefix would be Transistor the item could be NPN and the variant would be the pin mapping in the order of pin e.g.

 

Transistor_NPN_ebc

 

This is an NPN transistor with emitter pin 1, base pin 2 and collector pin 3

Our company is looking to implement a 6? digit part number and naming convention for our parts, and I'd love any ideas our thoughts you might have in how to go about setting up a good convention. At previous jobs we had good luck with such a system, so I'm very interested in establishing one here as well.

For that matter, if anyone has any good resources for some examples of naming conventions for parts, I'd be happy to take a look at what has been done elsewhere.

Thanks,

Jonathan

 

It's the millions of one-of-a-kind Logical Part Number for IC's where each individual electronic device has various pin assignments, logical part number, logical description, it's unique web-link to datasheet and pre-mapped to the correct IPC footprint name. These even contain Digi-Key links to order the parts.  

 

When we open the Parts On Demand (POD) the PCB Library Vending Machine and allow everyone to upload the manufacturer recommended schematic symbol for PCB Libraries, Inc. to sell to 6 million EE engineers worldwide, do you think anyone is going to purchase a resistor in every value? I don't think so. As a mater of fact I don't think we'll sell 1 resistor schematic symbol.

 

I am creating the entire Texas Instruments product line of library parts and there are 43,000 different logical part numbers and 43,000 different schematic symbols. No one will ever use them all, but they're all available to download, loaded with unique properties for each one, if anyone needs them.

 

 

I also agree with you guys that this has something to do with the software you use and even the part number naming convention in the PDM system. If we create duplicate symbols in library it will be hard for the librarians to maintain the library. We use Mentor DxDesigner-Expedition flow and we only have one resistor symbol for all Resistor part in library no matter their Manufacture, Value and package type. We use the same rule for other discrete components like capacitor and inductor and even the logical symbol.

If a DDR chip have three AML from TI, Fairchild and may be Samsung while actually they have the same footprint and symbol, we only need to have one symbol and the part name may be called 200-00001 for example. The EE can search this in PDM or Value in Databook to find this part. In our PDM we don't use Manufacture part number because sometimes we need second source for one part.

 

Thanks,

 

Nightwish

 

Not sure if I agree with your approach.  I think it definitely has to do with the tool you are using and how your library is setup, and the individual company's process.  For example, if you are using Cadence and utilize Part Tables, all of your manufacturer's & ordering information would be entered in a part table.  The schematic symbols would be given a generic name so it can be used with all manufacturer part numbers of the same type component, regardless of package.  The package information would be chosen from the part table.  This is true for Cadence Concept, Orcad Capture, DxDesigner, Cadstar and Altium - that I know of.  So for example lets use DS9367A from TI.  This part comes in 2 packages - an SO8 (DS9637ACM) and 8-pin Dip package(DS9367AMJ).  The pinouts are identical for both parts so you would only need ONE schematic symbol called DS9367A.  When the part is placed on a schematic, you would choose which package you'd want to use.  So creating all the extra symbols that are identical creates more overhead and maintenance.  You could still create individual libraries for each vendor if that makes sense for the company.  As I said, I think what tool you use drives how you should name your symbols.  Just my 2 cents.