真牛论坛怎么了

合理布局是PCB设计成功的第一步

time : 2019-11-16 09:27       作者:凡亿pcb

【FANYIPCB】ZAISHEJIZHONG,BUJUSHIYIGEZHONGYAODEHUANJIE。BUJUJIEGUODEHAOHUAIJIANGZHIJIEYINGXIANGBUXIANDEXIAOGUO,YINCIKEYIZHEIYANGRENWEI,HELIDEBUJUSHIPCBSHEJICHENGGONGDEDIYIBU。

YOUQISHIYUBUJU,SHISIKAOZHENGGEDIANLUBAN,XINHAOLIUXIANG、SANRE、JIEGOUDENGJIAGOUDEGUOCHENG。RUGUOYUBUJUSHISHIBAIDE,HOUMIANDEZAIDUONULIYESHIBAIFEI。

1、考虑整体

YIGECHANPINDECHENGGONGYUFOU,YISHIYAOZHUZHONGNEIZAIZHILIANG,ERSHIJIANGUZHENGTIDEMEIGUAN,LIANGZHEDOUJIAOWANMEICAINENGRENWEIGAICHANPINSHICHENGGONGDE。

ZAIYIGEPCBBANSHANG,YUANJIANDEBUJUYAOQIUYAOJUNHENG,SHUMIYOUXU,BUNENGTOUZHONGJIAOQINGHUOYITOUCHEN。

PCBSHIFOUHUIYOUBIANXING?

真牛论坛怎么了 SHIFOUYULIUGONGYIBIAN?

SHIFOUYULIUMARKDIAN?

真牛论坛怎么了 SHIFOUXUYAOPINBAN?

DUOSHAOCENGBAN,KEYIBAOZHENGZUKANGKONGZHI、XINHAOPINGBI、XINHAOWANZHENGXING、JINGJIXING、KESHIXIANXING?

2、排除低级错误

YINZHIBANCHICUNSHIFOUYUJIAGONGTUZHICHICUNXIANGFU?NENGFOUFUHEPCBZHIZAOGONGYIYAOQIU?YOUWUDINGWEIBIAOJI?

YUANJIANZAIERWEI、SANWEIKONGJIANSHANGYOUWUCHONGTU?

YUANJIANBUJUSHIFOUSHUMIYOUXU,PAILIEZHENGQI?SHIFOUQUANBUBUWAN?

真牛论坛怎么了 XUJINGCHANGGENGHUANDEYUANJIANNENGFOUFANGBIANDEGENGHUAN?CHAJIANBANCHARUSHEBEISHIFOUFANGBIAN?

真牛论坛怎么了 REMINYUANJIANYUFAREYUANJIANZHIJIANSHIFOUYOUSHIDANGDEJULI?

真牛论坛怎么了 DIAOZHENGKEDIAOYUANJIANSHIFOUFANGBIAN?

真牛论坛怎么了 ZAIXUYAOSANREDEDIFANG,ZHUANGLESANREQIMEIYOU?KONGQILIUSHIFOUTONGCHANG?

真牛论坛怎么了 XINHAOLIUCHENGSHIFOUSHUNCHANGQIEHULIANZUIDUAN?

真牛论坛怎么了 CHATOU、CHAZUODENGYUJIXIESHEJISHIFOUMAODUN?

XIANLUDEGANRAOWENTISHIFOUYOUSUOKAOLV?

3、旁路或去耦电容

在布线时,模拟器件和数字器件都需要这些类型的电容,都需要靠近其电源引脚连接一个旁路电容,此电容值通常为0.1μF。引脚尽量短,减小走线的感抗,且要尽量靠近器件。

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4、输入电源,如果电流比较大,建议减少走线长度和面积,不要满场跑

SHURUSHANGDEKAIGUANZAOSHENGOUHEDAOLEDIANYUANSHUCHUDEPINGMIAN。SHUCHUDIANYUANDEMOSGUANDEKAIGUANZAOSHENGYINGXIANGLEQIANJIDESHURUDIANYUAN。

RUGUODIANLUBANSHANGCUNZAIDALIANGDADIANLIUDCDC,ZEYOUBUTONGPINLV,DADIANLIUGAODIANYATIAOBIANGANRAO。

所以我们需要减小输入电源的面积,满足通流就可以。所以在电源布局的时候,要考虑避免输入电源满板跑。

5、电源线和地线

电源线和地线的位置良好配合,可以降低电磁干扰(EMl)的可能性。如果电源线和地线配合不当,会设计出系统环路,并很可能会产生噪声。电源线和地线配合不当的PCB设计示例如图所示。在此电路板上,使用不同的路线来布电源线和地线,由于这种不恰当的配合,电路板的电子元器件和线路受电磁干扰(EMI)的可能性比较大。

6、数模分离

在每个PCB设计中,电路的噪声部分和“安静”部分(非噪声部分)要分隔开。一般来说,数字电路可以容忍噪声干扰,而且对噪声不敏感(因为数字电路有较大的电压噪声容限);相反,模拟电路的电压噪声容限就小得多。两者之中,模拟电路对开关噪声最为敏感。在混合信号系统的布线中,这两种电路要分隔开。

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7、散热考虑

ZAIBUJUGUOCHENGZHONG,XUYAOKAOLVSANREFENGDAO,SANRESIJIAO;

REMINGANQIJIANBUYAOFANGZAIREYUANFENGHOUMIAN。YOUXIANKAOLVDDRZHEIYANGSANREKUNNANHUDEBUJUWEIZHI。BIMIANYOUYUREFANGZHENBUTONGGUO,DAOZHIFANFUDIAOZHENG。