To solve the problems of poor route ability in flexible printed circuit board

a bus planning algorithm based on pattern routing is proposed

which approximates detailed routing and reduces the precision error between detail routing and bus planning.At the same time

four routing patterns and several fan-out strategies are designed according to manual experience to simulate the possible situation of resource allocation in pin area and arrangement combination of pin areas.Besides

a layer assignment algorithm is designed to comprehensively evaluate the current routing results and the future impact on other nets.According to the restriction that vias are not allowed in the channel

the non-intersecting sequence of the routing topology of the nets in the channel is obtained according to the position sequence of pin areas connected with the channel

which is used as the constraint of the arrangement sequence of the points on the boundary line.Finally

the results in each pattern are comprehensively compared

and the least expensive result is selected as the final bus planning result. Experimental results on industrial cases show that the proposed algorithm realize better performance compared with the existing flexible printed circuit board bus planning algorithm.