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I've got a PCB design which contains a chip that uses the QFN (7x7) package.

Because of the package size the pins are very close together and the pads are 0.2mm apart, which is smaller than the minimum gap for soldermask colors other than green at PCBWAY and JLCPCB.

They mentioned they can still go ahead with the manufacture and assembly, but I'm wondering are there any risks that things will go bad during the assembly process especially for larger volumes?

Have anyone encountered similar situations with PCBWAY and JLCPCB before and can share their experiences?

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    \$\begingroup\$ If this is your first run I'd be more worried about things actually working rather then PCB color. \$\endgroup\$ Commented Jan 10, 2022 at 10:36

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It's quite certain that this will cause problems in the long run. I would recommend several steps:

  • check your footprint, maybe you can adjust the footprint a little to increase the solder mask bridge thickness to make it manufacturable for your PCB supplier.
  • switch to a higher PCB quality tier at your supplier (if applicable). You pay more, but the precision of the manufacturing is increased. Check their capabilities list.
  • switch to another PCB supplier. There are a lot of them out there, and most will not have any problems with that pitch of pins.
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