The quality acceptance of PCB shall include design, craftsmanship, and comprehensive approval. Generally, we should make samples first, test solder, seal the samples and then supply them in batches, including two aspects in detail.
First: the electrical connection performance inspection, usually self-inspected by the PCB manufacturer, the test instruments adopted are:
①The bare board tester (continuity tester) can measure the on and off of the connection wire, and whether the logical relationship of the multilayer board including the plated-through hole is correct;
②The automatic optical tester for graphic defects can check out the comprehensive performance of the PCB, including wires, characters, etc.
Second: manufacturability inspection, including PCB appearance, smoothness, flatness, clarity of characters, resistivity of via, electrical properties, heat resistance, solderability and other comprehensive properties to determine whether it can be accepted.
The above are the methods and steps on how to judge the quality of PCB, I hope it can help you!