What are the instructions for PCBA processing appearance inspection

What are the instructions for the appearance inspection of PCBA processing?

PCBA processing printed circuit boards, also known as printed circuit boards, printed circuit boards, often use the English abbreviation PCBA, which is an important electronic component, a support for electronic components, and a provider of circuit connections for electronic components. Because it is made using electronic printing technology, it is called a "printed" circuit board. Before the advent of printed circuit boards, the interconnection between electronic components relied on the direct connection of wires to form a complete circuit.

Now, the circuit breadboard only exists as an effective experimental tool, and the printed circuit board has become an absolute dominant position in the electronics industry. But most people still don’t know what the PCBA processing appearance inspection instructions are? Let's learn about it with the editor of PCBA processing.

PCBA processing appearance inspection instructions:

Missing parts: The components are not mounted as required in the corresponding position on the PCBA;

Empty soldering: 3/4 of the area of the solder joints without or less soldering of the component feet (SMD components are less than 1/2 of the width of the component);

Lian Xi: Due to abnormal operation, the two points that were originally unconnected were connected with tin;

Wrong parts: The components mounted on the PCBA do not match those shown on the BOM;

Weak soldering: The component pins are not well tinned, and effective soldering cannot be guaranteed (including fake soldering);

Cold welding: The surface of the solder joint is gray, without good wetting;

Reverse: The polarity after the component is mounted is opposite to that specified in the document;

Tombstone: One end of the patch component is lifted away from the pad, forming a tombstone;

Backside: The front of the component (the silk-screened surface) is facing down, but the welding is normal;

Open circuit: The component pin is disconnected or the circuit on the PCBA board is disconnected;

Tombstone: One end of the patch component is lifted from the pad to form a tombstone;

Backside: The front of the component (the silk-screened surface) is facing down, but the welding is normal;

Open circuit: The component pin is disconnected or the circuit on the PCBA board is disconnected;

Lifting: The copper foil or pad of the circuit is lifted from the PCBA surface and exceeds the specification;

Multiple pieces: The file indicates the location of no components, and there are components on the corresponding PCBA board;

Tin crack: Usually, after the solder joint is subjected to external force, the solder joint and the component pin are separated, which affects the soldering effect or hidden danger.