- #1
What is the Symbol for the Black Electronic Component?
- Thread starter weitao
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- Components Electronic
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Discussion Overview
The discussion revolves around identifying and describing a black electronic component, specifically focusing on its nature as an integrated circuit and the technique of chip on board (COB) assembly. The scope includes technical explanations and clarifications regarding the component's characteristics and manufacturing methods.
Discussion Character
- Technical explanation, Conceptual clarification
Main Points Raised
- Some participants identify the black component as an integrated circuit, noting its prevalence in inexpensive, mass-produced equipment.
- One participant describes the characteristics of integrated circuits, mentioning their resilience to vibration and moisture, but also highlighting that failure would necessitate discarding the entire printed circuit board.
- Another participant elaborates on the chip on board (COB) technique, explaining that it involves assembling an IC die directly onto a PCB without traditional packaging, which is common in high-volume manufacturing.
- Additional information is provided about the process of wire bonding and the protective covering of the die with black plastic.
- A participant inquires about the symbol for the black electronic component, indicating a desire for further clarification on its representation.
Areas of Agreement / Disagreement
Participants generally agree on the identification of the component as an integrated circuit and the use of the COB technique, but the discussion remains unresolved regarding the specific symbol for the component.
Contextual Notes
Some assumptions about the definitions of terms like "integrated circuit" and "chip on board" may not be fully articulated, and the inquiry about the symbol suggests a gap in the discussion that has not been addressed.
- #2
vk6kro
Science Advisor
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That is an integrated circuit. They are made like this in cheap, mass produced equipment.
I have seen one in a digital thermometer.
They look like a blob of plastic, but they are fairly immune to vibration and moisture. However if they failed, the whole printed circuit board would have to be discarded.
- #3
berkeman
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weitao said:
Just to add a little bit to vk6kro's post -- it's called "chip on board", or COB. It's a technique for assembling an IC die onto a PCB, without first injection molding the die into a plastic package with leads, and soldering that onto the PCB. As vk6kro says, it is used in high-volume manufacturing of inexpensive devices, generally, and does not offer any rework capability.
- #4
- #5
vk6kro
Science Advisor
- 4,079
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Yes, that one. It is an integrated circuit.
- #6
berkeman
Admin
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More info on COB:
http://www.siliconfareast.com/cob.htm
Once the die is wire bonded to pads on the PCB, it is covered by that black plastic blob to passivate it.
- #7
weitao
- 32
- 0
wat is the symbol?
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