Telink FR1 PCB Design Guideline
AN-22051900-E1 Ver. 1.0.0
9
2.2.2
Component and copper wire layer + carbon film and copper wire layer
One layer of this double-layer board is used to place components and copper wire routing, and the other
layer is for carbon film r copper wire routing. For example, in a remote control design, we place the
components on one layer and the keys on the other layer. The keys need to be designed as carbon film keys
and the keys routing is connected to the component layer via carbon film via holes. When there are many
components and the routing is complex, if the design shown in 2.2.1 cannot be completed routing, then in
addition to the carbon film routing on another layer, it is necessary to add copper routing and connect the
component side routing through the carbon film via holes. Note that carbon film vias are chosen for cost
concerns.
The board shown below can be designed as this type of double-layer board.
Figure 2-3 Double layer r carbon film routing
