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I a using an arduino and an ADXL335 accelerometer for a project, and trying to make the PCB for it. Unfortunately, all the eagle lbr files for these two components seem to be wrong. None of the lbr files match the actual pin configuration. Is this an issue during the schematic phase? Can changes to the pin locations be made in the board design phase? Or will the pin layouts have to be corrected in the schematic phase. If so, how can the components be adjusted to match the actual component layout?

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  • \$\begingroup\$ Its quite common for schematic symbols to have less pins than the actual package (NC, multiple GNDs and power connections, etc) but I personally never saw a symbol with more connections than a package. (Except arguably when 2+ pads are used in eagle to make a pad with a weird shape). Can you post images of what you are seeing? \$\endgroup\$ – Wesley Lee Dec 26 '16 at 19:16
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The arangement of the pins on a schematic symbol are irrelevant, as long as the pin number for a given function matches the PCB footprint pin number and position for that function.

For most ICs, the schematic symbol is designed for easy layout and understanding of the schematic, so the pin arrangement will rarely match the arrangement on the actual component.

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  • \$\begingroup\$ Would it matter if the actual component has only 5 ins, but the schematic has 15 pins (with a different layout)? (in the case of the adxl335) \$\endgroup\$ – user2883071 Dec 26 '16 at 17:45
  • \$\begingroup\$ Just make a new component \$\endgroup\$ – vicatcu Dec 26 '16 at 17:56
  • \$\begingroup\$ It is common practice to hide power and ground pins on the schematic symbol - there should be some way to display such hidden pins in Eagle. The NC (No Connect) pins need not be shown, as you don't have to connect to them. That leaves only four pins that need to be shown on the schematic symbol: ST, Xout, Yout, and Zout. \$\endgroup\$ – Peter Bennett Dec 26 '16 at 17:58
  • \$\begingroup\$ @Peter Bennett: INVOKE command. \$\endgroup\$ – Janka Dec 26 '16 at 18:00
  • \$\begingroup\$ Now that I know the NCs are redundant.. can I assume any of the COM pins to be ground? VS (VCC), ST (which is also required), X,Y,Z are also available. \$\endgroup\$ – user2883071 Dec 26 '16 at 19:05
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Download the script from http://www.newark.com/analog-devices/adxl335bcpz/accelerometer-3-axis-lfcsp-16/dp/45P6448 to generate a library (run the script from the library editor). That will be accurate, but check it of course.

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  • \$\begingroup\$ there aren't any scripts int he technical documents section \$\endgroup\$ – user2883071 Dec 26 '16 at 19:03
  • \$\begingroup\$ Under product information: CAD CadSoft_EAGLE (2.80KB) EN newark.com/webapp/wcs/stores/servlet/… \$\endgroup\$ – vicatcu Dec 27 '16 at 2:30
  • \$\begingroup\$ If down vote was because you couldn't find it, I respectfully request retracting it \$\endgroup\$ – vicatcu Dec 27 '16 at 2:33
  • \$\begingroup\$ I did not downvote it, I will, however, upvote it. \$\endgroup\$ – user2883071 Dec 27 '16 at 14:36

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