1
\$\begingroup\$

I can't find a tolerance measurement for the 62 mils thickness specified in the PCIe electromechanical spec. How much leeway do I have for board thickness in an add-in card.

Additional details: I'm trying to build a composite video (75 ohm single ended) PCIe add in card. For a 4 layer board, my fab house doesn't have a standard size core that would bring the stack up to exactly 62 mils.

\$\endgroup\$
1
\$\begingroup\$

The test specifications for at least one connector (items 3.1.5 and 3.1.6) suggest that the range of allowable thickness would be 1.44 to 1.70 mm (0.057 to 0.069 inches), which would be a tolerance of about ±8%.

\$\endgroup\$
  • \$\begingroup\$ Thank you. That seems to go with my fab's default tolerance of +-0.007". I was told IPC standards are +-0.010" which is too far out of tolerance. \$\endgroup\$ – lm317 May 30 '14 at 15:22

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.