• 作者: admin
• 来源: network
• 日期: 2014-11-28
• 浏览次数: 2477次

As it were, Chinese had just put CADSI as a routing process for a long period of time, as long as the schematic design is completed, as long as the line of a pull , the task is finished. This practice in low-end products pcb board, the density is not high, the signaling rate is low, the transmission line effect is not obvious in the case , it may be that the right - all the problems , whether it is EMC, signal integrity (SI), power integrity (PI), process issues, are tinkering with the way can be resolved . pcb board Therefore, at this stage , the company CADSI no need to invest is seen , not as some products do better pcb board.
 

But by the end of the stage, pcb board the situation is completely different. In the high-end products, we have seen progress in the design challenges :

1 , shrinking feature sizes , as well as the impact of Moore's Law , the signal transmission rate is getting higher and higher , steeper edges , so that transmission line effects can no longer be avoided , the signal line signal can no longer be seen as the ideal number signal , while the microwave to be treated should be treated , which appeared in "Black schematics" , a simple schematic logic has been unable to guarantee the correct signal properly implemented pcb board;

2 , more powerful circuits pcb board, enabling the board to increase the degree of integration , but the level of production technology production equipment limited by not immediately improve , leading CAD design to meet the current level of technology, design challenges increase ;

3 , control costs resulting veneer layers can not be infinitely increased with increasing density , and try to use low-cost devices , such as the use of ordinary 2mm connector instead of dedicated high-speed differential line connectors pcb board, EMC and systems lead to greater signal integrity challenging ;

4, the fierce market competition leads to shorten the product development cycle , has no extra time and money for the development of constant repetition ,pcb board veneer must be as a success , for the first time in the design must be considered to be productivity pcb board, testability , maintainability, and basically through the professional bodies on market access certification.