![integrated circuit - What kind of components are black blobs on a PCB? - Electrical Engineering Stack Exchange integrated circuit - What kind of components are black blobs on a PCB? - Electrical Engineering Stack Exchange](https://i.stack.imgur.com/eeENZ.jpg)
integrated circuit - What kind of components are black blobs on a PCB? - Electrical Engineering Stack Exchange
what causes the black corrosion /deposit on the pcb? | Electronics Forum (Circuits, Projects and Microcontrollers)
![What are these dark spots around my PCB trace, and should I worry about them? I tried to remove them with 99% IPA and a brush, but they won't come off. : What are these dark spots around my PCB trace, and should I worry about them? I tried to remove them with 99% IPA and a brush, but they won't come off. :](https://external-preview.redd.it/HqhvwxPWa4m3BRxgaJfjSBEx7DW69ICcf13q_EYutqU.jpg?auto=webp&s=48118beaa2cf6c80cae4ffd629de8bef9b7e4e1f)
What are these dark spots around my PCB trace, and should I worry about them? I tried to remove them with 99% IPA and a brush, but they won't come off. :
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