Professional PCB electronics manufacture services , every PCB enquiry or order is handled in the strictest of confidence.
FULL SERVICE PCB MANUFACTURING
TO PROVIDE HIGH QUALITY SERVICE,HIGE ACCURACY PRODUCTS AND HIGHT EFFICIENCY SOLOUTION TO THE CLIENTS
STRICT QUALITY CONTROL SYSTEM AND PASSED ISO CERTIFICATE
QUALITY CONTROL
For product quality, TOP PCB has been improving and attaching importance. Innovation is our spirit, is our quality, we are the soul，Monitor and coordinate production progress, continuously make improvement on this production plan, raise work efficiency and production quality, and coordinate work with various departments departments.we has been establishes quality system with ISO9001 and strictly implements the IPC class III standard to inspect the quality. 100% inspectionincludes electric test and AOI inspection. It can carry out high voltage test, impedance test,microsection , weldability test and otherprofessional tests to keep up with more demands from users of high-tech products.
high voltage test
impedance test
microsection
weldability test
Quality Control in PCB Design : In order to ensure quality in PCB design, your task should cover the following three aspects.
1, Validity of PCB design file has to be ensured: Project leader should be responsible for checking PCB design file and corresponding approval procedures have to be implemented so that validity of PCB design files has to be ensured.
2, Manufacturability of PCBs has to be ensured: Project leader and technologist should strictly conform to technological requirement in order to ensure manufacturability of PCBs. Technological requirement can be directly listed on design drawings if it is relatively simple. Otherwise, it has to be summarized into a text that is saved in additional file. No matter what is the simplicity of technological requirement, it has to be explained ACCURATELY, CLEARLY and REASONABLY.
3, Testability and Normalization has to be ensured: Standard implements normalization checking in terms of test points, structural style, dimensions, routing, through-hole via and characters so as to ensure testability and manufacturability of PCBs which should conform to requirement of national and industrial standardization.
Quality Control in PCB Manufacturing; In order to ensure quality in PCB design, your task should cover the following three aspects.
1, Capability of PCB manufacturers has to be ensured : Quality department, together with sourcing department should investigate and approve aptitudes and manufacturing capability of PCB manufacturers in order to ensure their sufficient manufacturing capability on your design project.
2, Checking and confirmation have to be constantly done prior to manufacturing : PCB designers have to check and confirm the design drawings that will be applied by PCB manufacturer for many times prior to manufacturing. Since PCB design can't be successful just after one trial and modifications have to be made time and time again, PCB manufacturers will hold multiple versions of design drawings. So it's necessary to carefully check and confirm the final design drawing provided by PCB manufacturer prior to practical manufacturing so that manufactured PCBs conform to requirement of the last version.
3 , Much attention should be paid to the key procedures of PCB manufacturing.
The quality of key procedures of PCB manufacturing influences a lot on performance and reliability of PCBs and quality control on that has to be strengthened. The key technological procedures formulated by PCB manufacturer have to be monitored and checked including etching, via mentalization etc. so as to ensure absence of burr, gap, bridge defect and void. Furthermore, quality control has to be overtaken on stacking of multi-layer PCBs in order to ensure the thickness, adhesive intensity and positional accuracy. Since gold plating is usually required by high-frequency PCBs and micro-strip boards, specific gold plating operation instructions have to be made in order to ensure the thickness and purity of plating plane.
Quality control in PCB inspection refers to monitoring and measurement of PCBs in strict accordance with inspection through visual inspection or the application of professional equipment. The inspection result has to be stored. If special requirement needs obtaining, specific acceptance rules have to be made additionally.
● Visual inspection
With the help of ruler, vernier caliper or magnifying glass, visual inspection is simple to be carried out. The inspected content includes:
a. Board thickness, surface roughness and warpage.
b. Dimensions of appearance and assembly, especially assembly dimensions compatible with electric connectors and lead rail.
c. Integrity and clearness of conductive patterns and existence of bridging short circuit, open circuit, burr or voids.
d. Surface quality, existence of pit, scratch or pin holes on printing traces or pad.
g. Coating quality. Whether plating flux is even and firm and position correct and whether flux is even and its color meets concerning requirement.
e. Positions of pad vias and other vias. It should be inspected that whether vias are missed or inaccurately punched, whether via diameter is compatible with design requirement or not and whether there are nodules and voids.
h. Character quality such as whether they're firm, clear and clean with no scratch, penetration or disconnection.
f. Pad plating quality and extent of firmness, roughness, brightness and void of bulge defect.
● General technological inspection
General technological inspection covers solderability and plating adhesion inspection. For the former, wetting performance of solder to conductive patterns is inspected. For the latter, it can be inspected by qualified tips that are first sticked to plating plane to be inspected and then are pulled off quickly after even pressing. Next, plating plane should be observed to ensure whether fall-off takes place or not. Furthermore, some inspections can be selected based on practical situations such as copper foil anti-falling intensity and metalized via anti-pulling intensity.
a. Connecting performance test. During this test, multimeter is generally applied to inspect the connectivity of conductive patterns with focus on metalized via of double-sided PCB and connectivity performance of multi-layer PCB. For this test, TOP PCB provides general inspection before each fabricated PCB leaves its warehouse in order to ensure the implementation of its basic functions.
b. Insulating performance test. This kind of test aims to inspect insulating resistor on the same plane or between different planes in order to ensure the insulating performance of PCB.
● General electrical performance inspection
There are two kinds of tests under this type of inspection:
● Metalized via inspectio
Quality of metalized vias plays a role of extreme significance for double-sided PCBs and multi-layer PCBs. Lots of breakdown happening to electric module or even the whole device lies in quality issues of metalized vias. Therefore, it's quite necessary to pay more attention to the inspection of metalized vias. Metalized via inspection covers the following aspects:
a. Metal plane of via wall should be complete, smooth and void of empty holes or nodules.
b. Electrical performance inspection should be carried out in accordance with short circuit and open circuit of pad and metalized via plating plane, resistance between via and leads.
c. Resistance change rate of vias shouldn't be over 5% to 10% after environmental test.
d. Mechanical intensity refers to adhesive intensity between metalized via and pad.
e. Metallographic analysis test is responsible for inspection in terms of plating plane quality, thickness and uniformity of plating plane, and adhesive intensity between plating plane and copper foil.
Metalized via inspection usually comes in combination of visual inspection and mechanical inspection. Visual inspection is to observe PCB with it placed under the light and complete and smooth via wall is capable of reflecting light evenly. However, via wall containing nodules or voids won't be so bright. For volume manufacturing, inspections should be implemented by on-line inspection equipment such as Flying Probe Tester. Apart from regular inspection items mentioned above, other inspection items include the following parameters concerning resistance of conductor, resistance of metalized vias, short circuit and open circuit of inner layers, insulating resistance between all lines, adhesive intensity of plating plane, adhesion, anti-heat shock, impact resistance to mechanical shock, current intensity etc. Each index has to be obtained through the application of professional equipment and methods.
