Mono-stable solderjoints
A mono-stable solderjoint is a solderjoint that never will create a solder bridge in a stable solder process. At a mono-stable solderjoint, the design of such joints in combination with its surrounding joints, makes it impossible to create solder bridges between such joints during separation from the solderwave. That is why they are called mono-stable, because there is only one stable situation. Even relatively large deviations from the optimal process settings will have no effect on such joints.
A good design will give sound joints without unwanted solderbridging. In other words: "Solder quality starts with design quality.
"Bi-stable joints / bridges
There are layouts where the solder can give sound joints without solder bridging, or create a solder bridge with the same process settings for what seems no clear reason. Nothing was changed in the soldering process, but for one "unclear “reason, now and then a solder bridge occurs, however always at the same area or at the same layout.
This "unclear" reason can be explained by the fact that some joints, due to their design, shows a bi-stable behaviour.
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