Q: Page 92. What is the definition of "routing class" of PCBs ?
The definition of the "Routing Class" of PCBs is described in the French standard NF C 93-713. The Routing Class characterizes the density of interconnection (and the tolerances for part placing). The following summary may be used:
|Minimal Width of routed tracks (mm)||0,80||0,50||0,31||0,21||0,15||0,12|
|Minimal spacing between both tracks or pads (mm)||0,68||0,50||0,31||0,21||0,15||0,12|
For a multi-layer PCB, the "Routing Class" is given by the layer with the highest density.
In a same layer, the routed area with the highest density defines the "Routing Class" of the layer.
For a complete definition of routing classes, refer to NF C 93-713.