PCB Libraries, Inc. | https://www.pcblibraries.com/Forum/qfn-thermal-via-pitch_topic2914_post11617.html
. According to the IPC-7093A you can also solder mask define the thermal pad to dam in the paste mask to prevent it from flowing into via holes
PCB Libraries, Inc. | https://www.pcblibraries.com/Forum/qfn-thermal-via-pitch_topic2914_post11613.html
. According to the IPC-7093A you can also solder mask define the thermal pad to dam in the paste mask to prevent it from flowing into via holes
PCB Libraries, Inc. | https://www.pcblibraries.com/forum/qfn-thermal-via-pitch_topic2914.html
. According to the IPC-7093A you can also solder mask define the thermal pad to dam in the paste mask to prevent it from flowing into via holes
PCB Libraries, Inc. | https://www.pcblibraries.com/Forum/topic2914&OB=ASC.html
. According to the IPC-7093A you can also solder mask define the thermal pad to dam in the paste mask to prevent it from flowing into via holes
PCB Libraries, Inc. | https://www.pcblibraries.com/forum/topic2914&OB=DESC.html
. According to the IPC-7093A you can also solder mask define the thermal pad to dam in the paste mask to prevent it from flowing into via holes
PCB Libraries, Inc. | https://www.pcblibraries.com/forum/topic2914&OB=ASC.html
. According to the IPC-7093A you can also solder mask define the thermal pad to dam in the paste mask to prevent it from flowing into via holes
PCB Libraries, Inc. | https://www.pcblibraries.com/forum/ipc7093a-btc-qfn-solder-mask-defined-thermal-pad_topic2154_post11220.html
. Random via location makes the solder mask defined thermal pad much more complex to create symmetrical paste mask aperture openings. For the balancing of the package during reflow, it's important to have even paste mask distribution
PCB Libraries, Inc. | https://www.pcblibraries.com/forum/ipc7093a-btc-qfn-solder-mask-defined-thermal-pad_topic2154_post10556.html
. The thermal pad solder mask was 1:1 scale of the thermal pad. During reflow the paste would melt and travel down the via holes. The PCB designer might have created a fabrication note to plug the holes on the Thermal Pad not knowing that it would increase cost by 10 - 15
PCB Libraries, Inc. | https://www.pcblibraries.com/forum/topic2154&OB=ASC.html
. Random via location makes the solder mask defined thermal pad much more complex to create symmetrical paste mask aperture openings. For the balancing of the package during reflow, it's important to have even paste mask distribution
PCB Libraries, Inc. | https://www.pcblibraries.com/forum/advice-for-solder-mask-paste-mask-layers_topic484_page1.html
% area reduction in the thermal pad of a QFN package. 3. Maybe it is not directly your advice but somewhere I red about putting solder mask on these thermal via to avoid solder paste wicking. 4. The solderdam
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