20L Rigid PCB Layout

Description

Type	20L Rigid PCB Layout
Difficulty	1.Very small, its main board is half the size of a common cell phone board. 2.Strange shape results in great limits for routing;  3.GSM & WCDMA dual-mode cell phone results in a large radio-frequency area. 4.Super-thin cell phone solution limits the board thickness; placing the whole radio-frequency module under the baseband chip results in great limits in hole drilling on the baseband chip; 5.Originally, ALIVH materials was to be used, but considering cost and risk reduction, we used second-order buried via scheme, but the  routing requirements were not degrade.
Countermeasure	1.By discussing with multiple PCB manufacture team, we set appropriate design parameters; 2.With RF experts’ participation in PCB design, strict design process assured signal quality of the board; 3.Careful optimization achieved the best coordination among requirements of different parties;
Result	Design fulfilled according to the plan, successful CAM and smooth debugging.