A legend print / marking print (also refered to as: silkscreen or screen printing) is helpful for error-free manual assembly, but also for including a revision number, adding a company logo, warning labels or UL-number on the circuit board.
Legend print is usually applied using the silkscreen process. For small quantities, e.g. prototypes in express service, DLP (Direct Legend Printing) - similar to an inkjet printer - can also be used.
Multi-CB can provide legend prints in the colours white (standard) as well as red, yellow, and black.
Solder pads should never be overprinted, because this may lead to problems during soldering, assembly, and with the E-Test. If we should detect an overprinted solder pad (spacing < 150µm), then Multi-CB reserves the right to remove the legend print at this location. Relevant for the definition of the solder pads is the solder pad exemption. The legend print is usually automatically clipped with a spacing of 100µm to the solder-stop edge.
Legend print parameters
Min. spacing to pads | 150µm |
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Font height | Optimum font width |
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1,2mm | 150µm (6mil) |
1,8mm | 200µm (8mil) |
Legend print placement
The spacing between solder pad and marking print should be at least 150µm.
Always avoid overprinting solder pads!
Note for EAGLE users
Note for EAGLE users
Before exporting your data, you should always activate the option "Always vector font", which is found under: Options / User interface. Otherwise your legend print will very probably be incorrectly applied (see EAGLE 5-Manual, page 44).