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When I design my circuit, I'm confused and made the wrong connection. I connected my microprocessor to second pin instead of third pin of cyrstal. But I left the third pin blank. So when my circuit come from manufacturer, I can solder pins 2 and 3 and problem fix. Is this solution to work ? According to datasheet second pin must connect to ground.

This is datasheet. https://www.mouser.com.tr/datasheet/2/905/c_NX3225SA_e-1317523.pdf

And my circuit. enter image description here

*Capacitors connected to second pin.

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2 Answers 2

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You can short 2 & 3.

However I would check if 2 is not connected to the case. In that case I would prefer to remove the connection of 2 and the CPU.

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  • \$\begingroup\$ Can you explain why a connection between 4 and 2 is important? What difference does it make? \$\endgroup\$ Commented Aug 28, 2019 at 17:11
  • \$\begingroup\$ I can not cut connection between second pin and cpu according to datasheet 2 and 4 are connected. \$\endgroup\$ Commented Aug 28, 2019 at 17:13
  • \$\begingroup\$ Yes, at zoom of 150% I noticed the very small print that 2 & 4 are connected to the case. If you can't, you can't. In which case my answer mirrors hacktasatic and I will delete it in a few minutes. \$\endgroup\$
    – Oldfart
    Commented Aug 28, 2019 at 17:18
  • \$\begingroup\$ It looks like you have room to cut the trace to pin 2. Can you edit your question with a bit wider view of your circuit board? Things would have to be awfully tight to keep you from doing a cut & jump there. \$\endgroup\$
    – TimWescott
    Commented Aug 28, 2019 at 17:25
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Pins 2 and 4 are connected to the crystal case. You will need to cut the trace to pin 2 and reconnect it to pin 3. That should work until you can fix the board layout.

For sure you will need to isolate pin 2 unfortunately. The case adds too much parasitic capacitance. Normally the case is grounded, you should also include this when you roll the layout.

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