... solder mask is to be removed are placed in direct contact with both sides of the panel. The panel is then exposed to UV | CIRCUIT BOARDS | light. The amount of light used is controlled by an integrator. Printing is done with a semi-automatic dual drawer printer. While one drawer is being | CIRCUIT BOARDS | loaded with a panel and phototools, the other is inside the machine being exposed. This dual drawer printing system runs at the same rate as | CIRCUIT BOARDS | the screen printer to insure continuous flow. Develop LPI Mask After the panel has been exposed, it is placed in a vertical developer. The unexposed | CIRCUIT BOARDS | solder mask is dissolved in a high pressure spray of developing solution. The solution temperature, concentration and conveyor speed control the development process. The developer | CIRCUIT BOARDS | solution concentration is maintained by a feed and bleed system controlled by pH. After development, the panels are rinsed and dried. Cure LPI Mask As | CIRCUIT BOARDS | panels exit the solder mask developer, they are automatically loaded into the conveyorized curing oven. ...
[ Circuit Boards ]


... enough to permit a 0.007" air gap. SOLDERMASK CLEARANCE Bottleneck: Many Gerber files for soldermask come with the clearance for the features as one-to-one. | CIRCUIT BOARDS | If the manufacturer left this artwork as is, the result will be end product with soldermask on lands. This is not acceptable in most cases, | CIRCUIT BOARDS | though IPC standards permit encroachment on one side of the feature (for surface mount). By providing the soldermask data this way, it requires the CAM | CIRCUIT BOARDS | operator to increase all features by the requirement of the manufacturer. Some potential errors: * The manufacturer's requirement may be at a different specification than | CIRCUIT BOARDS | the designer's. * Exposed trace features. * Slivers of soldermask may be left behind after increasing and shaving and redeposit on other areas of the | CIRCUIT BOARDS | part. * Increase of clearances designed to have soldermask on that feature. Often, Gerber files for soldermask are so large that CAM software triggers an | CIRCUIT BOARDS | error in the design. This causes the artwork to be questioned and ...
[ Circuit Boards ]


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