Keyword: layer board, printed circuit board, PCB manufacturing
A overlap, welding plate
1, the bonding pad (except this surface welding) overlap, mean pore of overlap, drilling in the drilling process in a multiple result in broken bits,
leading to loss of hole.
2, two holes in a multilayer overlap, such as for the isolation of a hole plate, a hole for the connection plate (pad), after paint film performance for
isolation plates, scrap.
B, the graphics layer of abuse
1, in some attachment did some useless graphics layer, was four layer board is designed five floors above the line, make the misunderstanding.
2, when the design graph save trouble, with Protel software as an example for some lines in every layer Board layer to paint, and with Board layer
to delimit dimensioning lines, which, when light painting data layer Board, because not to miss the attachment and open circuit, or because of the
selection Board layer labeling lines and short circuit, so keep the graphics layer when the design is complete and clear.
3, in violation of the conventional design, such as component design on the Bottom floor and welding surface design on the Top, causing
inconvenience.
C, the character of the place
1, characters cover solder SMD soldering terminal, on-off testing and components to printed circuit board welding inconvenience.
2, the character design is too small, resulting in the difficulty of the silk screen printing, overlapping characters of too much, it is difficult to
distinguish.
D, one side welding plate aperture Settings
1, one side welding plate is generally not boring, if hole needs to mark, the aperture shall be designed to zero. If the numerical design, drilling
data, the result in this location hole in the ground, and problems.
2, one side welding plate such as drilling should be special mark.
E, the paint filled block welding plate
Welding plate with filling piece picture when designing circuit can through the DRC check, but for processing is not enough, so kind of bonding
pad can not directly generate resistance welding data, in resistance welding flux, the filling area will be covered by resistance welding flux,
welding difficulties in device.
F, electricity formation spent solder and attachment
Because designed to take the power of the way of bonding pad, the formation and the actual image on the printed circuit board is on the
contrary, all attachment is shielded wire, the designer should be very clear on this point. Here, by the way, drew a few set of power supply or a
tiller of the ground isolation should be careful, can't leave a gap, the short circuit of two sets of power supply, also do not make the connection of
regional blockade (make a set of power supply is separately).
G, the processing level definition is not clear
1, single panel at the TOP layer design, such as do not show positive and negative, perhaps out of board mount devices and bad welding.
2, for example, when a four layer board design adopts the TOP four mid1, mid2 bottom layer, but the process is not placed in this order, this
request.
H, in the design of filling with very fine thread too much or filling blocks of fill
1, produce light painting data have lost phenomenon, light painting incomplete data.
2, for filling block when light painting data processing is a a thread to paint, so the light painting data volume is quite large, increased the difficulty
of data processing.
I, surface-mount devices welding plate is too short
This is for on-off testing, for SMT components is too close, the spacing between the two feet is fairly small, welding plate is also quite thin,
installation testing needle, must be up and down (or so) crisscross position, such as welding plate design is too short, although does not affect
the device installation, but can make the test needle wrong doesn't open.
J, large area of the grid spacing is too small
Of the edge of the area between grid lines and lines are too small (less than 0.3 mm), in the process of PCB manufacturing, figure after turning
process on the shadow prone to a lot of film adhesion on the board, bolt.
K, large area of copper foil too close to the distance away from outside the box
Large area of copper foil from the outer frame should ensure at least 0.2 mm above the spacing, because when the milling shape such as milling
on the copper foil cause copper foil case become warped and flux loss caused by the resistance problem.
L, shape frame design is not clear
Some customers Keep layer, Board layer, Top over layer design of the contour line and the contour line is not coincidence, cause the PCB
manufacturer which is difficult to judge by the contour line will be final.
M, graphic design, uneven
When making graphics plating coating uneven, affect the quality.
N and application in copper too grid lines, avoid bubbles when SMT.
Source: //www.seekic.com
