... intact although the polyethylene packages capability of keeping humidity away is not really reliable. A.3 2 ) Storage time The storage time of PCB`s | CIRCUIT BOARDS INDUSTRY | should be as short as possible. PCB`s should be taken out due to the „first-in, first out“ rule. The the polyethylene packages should be taken | CIRCUIT BOARDS INDUSTRY | away just before the assembling. Remaining PCB`s should be repacked again. To avoid exposure to draught, the packages should be stored in boxes. A.4 3 | CIRCUIT BOARDS INDUSTRY | ) Soldering tests PCB`s stored for over several months and being transported under questionable conditions, should be submitted again to a soldering test, being equivalent | CIRCUIT BOARDS INDUSTRY | to your soldering process. A.5 4 ) Heat conditioning of the PCB`s In any case we suggest a drying process of the PCB`s in a | CIRCUIT BOARDS INDUSTRY | stove to reduce the moisture in the PCB`s to an acceptable minimum. Following parameters can be recommended: A6) Drying time: Temperature C° 8 hours 120 | CIRCUIT BOARDS INDUSTRY | 10 hours 100 18 hours 80 Lower drying temperatures are also possible but need much more exposure time. ...
[ Circuit Boards Industry ]


... lots of unnecessary positive planes swell exponentially, bog down CAM systems, and crash photoplotters. After the basic prep work is completed, step into the | CIRCUIT BOARDS INDUSTRY | fabrication | PRINTED CIRCUIT BOARDS | analysis arena, where the game is one of checks and balances. You've got your design rules; fabricators have theirs. | CIRCUIT BOARDS INDUSTRY | Checks and balances can resolve any conflicts between the two. | TAKE SOLDERMASK LAYERS |, for instance. Often, these layers are not "intelligent" layers within | CIRCUIT BOARDS INDUSTRY | a CAD tool; that is, there is not much in the way of capability checking within the tool. As a result, these are among the | CIRCUIT BOARDS INDUSTRY | more troublesome layers for fabricators. The solution here is a fabrication analysis tool that can handle such issues as clearances, coverage, webbing, and so forth. | CIRCUIT BOARDS INDUSTRY | For instance, most fab shops want the largest possible | CLEARANCES | in a solder layer so that mask doesn't end up on pads. On | CIRCUIT BOARDS INDUSTRY | the flip side, copper is not supposed to be exposed. The two requirements - no mask on pads and ...
[ Circuit Boards Industry ]


... must be supplied with each new job and should contain the following information to ensure that the finished board is to your requirements. - | CIRCUIT BOARDS INDUSTRY | Always required even when a drill file is supplied, to enable inspection of panels immediately after drilling and finished boards prior to despatching. Hole sizes | CIRCUIT BOARDS INDUSTRY | must be clearly represented with distinct differences between each size. Tolerances are not required unless different to our standard of +0.1 / -0.05 mm. - | CIRCUIT BOARDS INDUSTRY | Preferred with overall mechanical dimensions including notches, cutouts and slots. Also preferred is a positioning (datum) dimension (drilled hole is best). Tolerances are not required | CIRCUIT BOARDS INDUSTRY | unless different to our standard of + / -0.25 mm. Other information required for all boards includes: board thickness (standard = 1.6mm) base copper thickness | CIRCUIT BOARDS INDUSTRY | (std = 18mm) solder mask colour (std = green) solder mask type (std = liquid photoimageable) component legend colour (std = white) bare board testing | CIRCUIT BOARDS INDUSTRY | requirement (std for multilayer and ...
[ Circuit Boards Industry ]