Products Introduction
A company's3Gsmart phones,support GSM / CDMA dualnetwork dual standby,hasbig capacitivetouchscreen, WiFi, BT, SDexpansion,stereospeakers, high-speedUSB2.0 interface,high-resolutioncamera,optoelectronic sensorlightsand so on.

Design parameters
3000 physicalpin,design densityhigher than0.05 (board size/14pin-components), 8-layerPCB, 5-layersignal(includingthe surface), 3-layerGND andPOWER,small boardsize,blindburied via design.

Mixed digital and analog signals:
A variety ofmixeddigital and analogsignalscross together,we must ensure thatall network workthroughbut also ensure the quality ofalldigital and analogsignals.

(Takepackageprocessing to analog signalto avoid high-speed digitalsignal of theadjacent layersandmaintainthe ground integrity of reference layer)

Complex power system:
According to the size, it can bedivided into20 types. We needto control andensurethe normally operation of complexpower system, but alsoneed to coordinatethepower and the interferencebetweendigital and analogpart.

Small boardsize:
Restrict with structure sizeandappropriateinterfaceslocationas well as number of layers;withoutcompromising expandingspace; layout one side of the whole boardand highdensity. All in all, it is difficult to design. Although the space is small,we need to ensure that there is sufficientspace to set nearly10shields.

Adopt blind and buriedviadesign:
we have 1-2,2-7,7-8,1-8designsand be able toensure that current capacity which required by dozens ofloadsof phoneitself.

EMI / EMC problems:
Betweenall designedsignalandthe reference plane,essentially we don’tcross-reference planeto ensurethe integrity ofSIand wewiden thedistance betweenthe signalto ensureEMI,andallother space to be made groundingto preventEMCproblems.