51W High Power Automobile Lighting PCBA
Notes for selective wave soldering carrier and PCB circuit design:
When traditional plug-in soldering pins too close to the edge of carrier, it's easy to lead to solder insufficiency due to shadow effect.
The carrier must cover those parts that do not require to be soldered with tin stoves.
It is recommended to keep at least 0.05"(1.27mm) thickness for edge wall of carrier broken hole to ensure tins not penetrates into the parts that do not need to be soldered by the tin stoves.
For the part requiring soldering of tin stoves,it is recommended to keep at least 0.1"(2.54mm) for the broken hole-edge distance to reduce the possible shadow effect.
The height of the overside parts should be less than 0.15"(3.8mm), otherwise the stove carrier will not be able to cover the high parts.
1. The SMD soldering plate of character cover soldering pad brings inconvenience to PCB boards on-off test and components soldering.
2. If character design is too small, will make silkscreen printing difficult;if too large, will make them overlap each other and difficult to be distinguished.
Setting hole diameters of single-sided pad
1. Generally single-side pad is not drilled. If drill needs to be marked, the hole diameter shall be designed to be zero.If values are designed, will appear hole coordinates at this position when drilling hole data is generated, and lead to some problems.
2. Single-sided PCB pads shall be specially marked if drilling.
Draw the pad with the filling block
Using filling block draw pads can pass DRC inspection in circuit design, but it is not suitable for processing. Because this kind of solding pad cannot directly generate solder mask data. When soldering flux is used, the filling block area will be covered by soldering flux, resulting in the device welding difficulty.
Because the power is designed to a splay pad, the ground layer is opposite to the actual image on PCB board, and all the circuits are insulated.By the way, you should be careful when drawing a few powers or several types of isolation lines, don't leave a gap, will make short circuit for the two powers, or block the area where the connection is made.