Difference between revisions of "PCB Component Footprint Validation Procedure"
From apertus wiki
| Line 13: | Line 13: | ||
# Most of the time either the manufacturers website or the distributors (farnell, RS, digikey, mouser) will offer them for download. | # Most of the time either the manufacturers website or the distributors (farnell, RS, digikey, mouser) will offer them for download. | ||
# Add the partnumber and datasheet URL to the partlist table | # Add the partnumber and datasheet URL to the partlist table | ||
# Each part in the part list has a library name, we can open this library in Eagle. | # Each part in the part list has a library name, we can open this library in Eagle. | ||
# Extract the "libraries archive" in the files section | # Extract the "libraries archive" in the files section | ||
| Line 19: | Line 18: | ||
# Once the library window opened go to Library -> Package and choose the one matching the devicename in the partlist | # Once the library window opened go to Library -> Package and choose the one matching the devicename in the partlist | ||
=== The actual checks === | |||
## Check if the pitch & position of all pads matches the specifications in the datasheet [[File:Footprint-dimension-check-01.jpg| 400px]] | # Each used part in the library must be validated against the original dataset | ||
# Check if the pitch & position of all pads matches the specifications in the datasheet [[File:Footprint-dimension-check-01.jpg| 400px]] | |||
# For through-hole parts check if all pins are fully surrounded by pads (green) - SMD components have red SMD pads | |||
# check if the pin numbering/naming (under "Device") is matching the datasheet [[File:Pin-numbering-check01.jpg| 400px]] | |||
==Component Selection== | ==Component Selection== | ||
Revision as of 22:46, 9 February 2015
1 Preparations
- Install Eagle Freeware edition: http://www.cadsoftusa.com/download-eagle/ and choose "Freeware license" when running it for the first time. (OSX Experience: you need to start it twice in freeware mode)
- Download *.brd,*.sch and library archive of a project PCB
- Open the *.brd or *.sch file in Eagle and go to File -> Export -> Partlist
- Save the partlist as text file and add it to the wiki page of that PCB
2 Verification
2.1 Footprint validation
- The saved partlist contains several columns, the "device" and "library" are the most important. (note: "0402" components are standard SMD parts and the footprint will likely be just fine, more important are the non standard parts)
- Pick a line from the partlist and use a search for a datasheet of the "device" with the entire partnumber.
- Most of the time either the manufacturers website or the distributors (farnell, RS, digikey, mouser) will offer them for download.
- Add the partnumber and datasheet URL to the partlist table
- Each part in the part list has a library name, we can open this library in Eagle.
- Extract the "libraries archive" in the files section
- In Eagle go to Library -> Open and select the matching library from the extracted files that you want to inspect.
- Once the library window opened go to Library -> Package and choose the one matching the devicename in the partlist
2.1.1 The actual checks
- Each used part in the library must be validated against the original dataset
- Check if the pitch & position of all pads matches the specifications in the datasheet
- For through-hole parts check if all pins are fully surrounded by pads (green) - SMD components have red SMD pads
- check if the pin numbering/naming (under "Device") is matching the datasheet
2.2 Component Selection
- for parts that have no value defined yet check the recommendations and research matching parts
- For guidance on part selection specifics ask Bertl on IRC. (optimally provide him with PCB version/revision identification and partlist numbers so he knows exactly what you are talking about)
- search for alternative equivalent parts
- help us find the best price from mouser, digikey, farnell, RS, etc.