Tag Archives: flexible pcb

The performance and thickness of common adhesive tape of flexible pcb

Posted by on March 4, 2014 No comments

Today we here to know the performance and thickness of common adhesive tape of flexible pcb, please see below:

1. 3M9077: thickness 0.05mm; afford high temperature, can be posted before soldering;

2. TESA8852: Thickness 0.05mm; afford high temperature, can be posted before soldering;

3. TESA4972: Thickness 0.05mm; canot afford high temperature; can not be posted before the soldering , but with strong adhesive;

4. TESA4982 Thickness 0.1mm; canot afford high temperature; can not be posted before the soldering , but with strong adhesive;

5. TESA68644 Thickness : 0.1mm; afford high temperature; can be posted before soldering;the adhesive is stronger than others ;

6. 3M467: Thickness :canot afford high temperature; can not be posted before the soldering;

(This tape using only under customers’ special requirements )

7. DK1042 ( conductive adhesive ) : Thickness:0.1mm;canot afford high temperature; can not be posted before the soldering;

8. FC2017 ( conductive adhesive ) : Thickness:0.1mm;canot afford high temperature; can not be posted before the soldering;

9. 3M conductive adhesive : Thickness : 0.05mm; high temperature;need hot pressing and tp be posted before the patch ;

10.18UM pure adhesive : Thickness : 0.018mm; high temperature;need hot pressing and tp be posted before the patch ;

11.25UM pure adhesive : Thickness : 0.025mm;high temperature;need hot pressing and tp be posted before the patch.

CMD Circuits have the all kinds of the adhesive tapes, if you have the inquiry of flexible pcb, please contact us anytime.

Flexible PCB Frequently Asked Questions

Posted by on November 27, 2013 No comments

In the life of flexible pcb issues are concerned, besides the both ends of the flexible pcb to rigid pcb or the connector for connection problems, for the flexible pcb is the ultimate serious consequences – broken.

In order to prevent the flexible pcb is broken in use for some time, we should try to exclude flexible pcbin the folding process of the problems encountered. Described below is our common problems and common solutions:

1. FPC and housing has scratches.

(1) allows the plant to do some transparent mold shell, installed over the whole observed after FPC hole in the state of motion to find the location of the interference with the housing flexible pcb, flexible pcb by changing the length to resolve the issue.

(2) one of the oldest methods, that is, not flexible pcbsamples, we can put flexible pcb 2D drawing paper 1:1 print out (hard to try some of the paper), cut out the shape, carefully fitted to the phone, instead of flexible pcb discover and analyze and solve problems. Or do some manufacturers do not allow the alignment, only the rough shape of the flexible pcb samples, loaded to the phone analysis.

(3) on the FPC can be in contact with the aperture where a layer of foam stickers, so that when the case does not directly turn in contact with the flexible pcb, thereby reducing damage to the FPC in order to increase its life. However, this method is a kind of stopgap feeling, it is best to find a cause from the design itself to be truly resolved.

(4) In order to avoid scratching flexible pcb and the housing has, often foreign practice is to install an iron shaft housing, FPC is fixed to the Iron shaft, to avoid opening and closing the clamshell flexible pcb and the housing crash, friction.

(5) Now a lot of rotating clamshell + phone first consideration in the selection of the FPC FPC around the shaft, or simply using coaxial cable coaxial cable instead of FPC, FPC and easy to avoid distortion or breakage problems.

2. FPC in the folding process of abnormal sound.

(1) FPC in the shaft hole length exceeds the diameter (the lid, there is no interference), but open to a certain angle, FPC will be a twisting process, it will run into the hole wall, we abnormal sound can be heard. FPC common solutions to reduce the length to ensure that the folding does not scratch and can work with the inner wall;

(2) FPC itself is multi-layered, and the inner wall of the hole in the lid when it has interference, so when the flip is always abnormal sound can be heard. We can enable manufacturers tied with tape or glue the layers together seemingly layer, but not in the best part about the folding stick together, keep multilayer structure. flexible pcb same length can be reduced.

Above for flexible pcb and housing has scratches and the flexible pcb discussion abnormal sound, there are many times exist simultaneously, the solution also co-exist.

The above analysis only for the analysis of the most common problems and solutions, in future work may encounter more problems and solutions, and then gradually improve the data.

Flexible pcb connections and testing ways

Posted by on June 26, 2013 No comments

Flxible pcb connections have main two kinds: plug and welding ways. Flexible pcb plug that is inserted into the connector inside, then FPC insertion end and Goldfinger designed according to the spec. of connector. Welding that is Flexible pcb can be soldered to the PCB board, may also be welded to the B2B connector.

As for the Flexible pcb testing, some performance tests are done by the manufacturers, but also can meet the requirements of mobile phones, we are not discussed here. We are most concerned about is the life issues. FPC life in addition to considering the structural design of factors, the most important is to consider the FPC materials. In the selection of the copper foil is best to choose a good rolled copper foil.

About the life test, the best way is through the experiment, through a dedicated folding machine experiment, with automatic counting function, you can test out the Flexible pcb in the normal operating range can be folded up to the number of times. Not yet found what software can simulate analysis. As for the test results can reach tens of thousands of times, different mobile phone manufacturers and the market have different standards.

Outgoing Quality Inspection of flexible pcb

Posted by on August 9, 2012 No comments

This time let’s see the outgoing quality inspection of flexible pcb, so you can see how can we control the quality of flexible pcb. See below our test items:

1. The material of your required. Include the based material,coverlayer,stiffener,silkscreen, etc
2. Testing: Peel strength, Chemical resistance test, Bending test, Thermal stree test;
3. Finished treatment;
4. Outline dimension;
5. 100% open/short testing of flexible pcb;
6. Appearance inspect.

After these inspect items, then we will pack the flexible pcb goods, and send out.

The production tolerances of flexible pcb

Posted by on August 6, 2011 No comments

Would you like to know the flexible pcb production capabilities and tolerances of CMD circuits? Please see below CMD can make for you.

1. tolerance of overall thickness   +/-0.03mm
2. positional and dimensional tolerance of edges and holes   about +/-0.10mm
3. minimum trace width and spacing (1/2 oz. copper)     0.05mm/0.05mm
4. minimum distance of traces and holes to an edge of the flex pcb 0.15mm, better is 0.20mm

These are the most common tolerances of the flexible pcb, if your board have more strict required, please send us to check if we can make.

CMD Circuits specilize in making flexible pcb, flexible circuits, rigid pcb, aluminum pcb.