描述
目前,PCB已然成为“电子产品之母”,其应用几乎渗透于电子产业的各个终端领域中,包括计算机、通信、消费电子、工业控制、医疗仪器、国防军工、航天航空等诸多领域。那么PCB是如何设计出来的呢?
1、前期准备
包括准备元件库和原理图。在进行PCB设计之前,首先要准备好原理图SCH元件库和PCB元件封装库。
PCB元件封装库最好是工程师根据所选器件的标准尺寸资料建立。原则上先建立PC的元件封装库,再建立原理图SCH元件库。
PCB元件封装库要求较高,它直接影响PCB的安装;原理图SCH元件库要求相对宽松,但要注意定义好管脚属性和与PCB元件封装库的对应关系。
2、PCB结构设计
根据已经确定的电路板尺寸和各项机械定位,在PCB设计环境下绘制PCB板框,并按定位要求放置所需的接插件、按键/开关、螺丝孔、装配孔等等。
充分考虑和确定布线区域和非布线区域(如螺丝孔周围多大范围属于非布线区域)。
3、PCB布局设计
布局设计即是在PCB板框内按照设计要求摆放器件。在原理图工具中生成网络表(Design→Create Netlist),之后在PCB软件中导入网络表(Design→import Netlist)。网络表导入成功后会存在于软件后台,通过Placement操作可以将所有器件调出、各管脚之间有飞线提示连接,这时就可以对器件进行布局设计了。
PCB布局设计是PCB整个设计流程中的首个重要工序,越复杂的PCB板,布局的好坏越能直接影响到后期布线的实现难易程度。
布局设计依靠电路板设计师的电路基础功底与设计经验丰富程度,对电路板设计师属于较高级别的要求。初级电路板设计师经验尚浅、适合小模块布局设计或整板难度较低的PCB布局设计任务。
4、PCB布线设计
PCB布线设计是整个PCB设计中工作量最大的工序,直接影响着PCB板的性能好坏。
在PCB的设计过程中,布线一般有三种境界:
首先是布通,这是PCB设计的最基本的入门要求;
其次是电气性能的满足,这是衡量一块PCB板是否合格的标准,在线路布通之后,认真调整布线、使其能达到最佳的电气性能;
再次是整齐美观,杂乱无章的布线、即使电气性能过关也会给后期改板优化及测试与维修带来极大不便,布线要求整齐划一,不能纵横交错毫无章法。
5、布线优化及丝印摆放
“PCB设计没有最好、只有更好”,“PCB设计是一门缺陷的艺术”,这主要是因为PCB设计要实现硬件各方面的设计需求,而个别需求之间可能是冲突的、鱼与熊掌不可兼得。
例如:某个PCB设计项目经过电路板设计师评估需要设计成6层板,但是产品硬件出于成本考虑、要求必须设计为4层板,那么只能牺牲掉信号屏蔽地层、从而导致相邻布线层之间的信号串扰增加、信号质量会降低。
一般设计的经验是:优化布线的时间是初次布线的时间的两倍。PCB布线优化完成后,需要进行后处理,首要处理的是PCB板面的丝印标识,设计时底层的丝印字符需要做镜像处理,以免与顶层丝印混淆。
6、网络DRC检查及结构检查
质量控制是PCB设计流程的重要组成部分,一般的质量控制手段包括:设计自检、设计互检、专家评审会议、专项检查等。
原理图和结构要素图是最基本的设计要求,网络DRC检查和结构检查就是分别确认PCB设计满足原理图网表和结构要素图两项输入条件。
一般电路板设计师都会有自己积累的设计质量检查Checklist,其中的条目部分来源于公司或部门的规范、另一部分来源于自身的经验总结。专项检查包括设计的Valor检查及DFM检查,这两部分内容关注的是PCB设计输出后端加工光绘文件。
7、PCB制板
在PCB正式加工制板之前,电路板设计师需要与PCB甲供板厂的PE进行沟通,答复厂家关于PCB板加工的确认问题。
这其中包括但不限于:PCB板材型号的选择、线路层线宽线距的调整、阻抗控制的调整、PCB层叠厚度的调整、表面处理加工工艺、孔径公差控制与交付标准等。
产品承诺:
保 证 全新原装进口,
保 证 安全准时发货,
保 证售后服务质量,
优势价格,大量现货。
主营DCS系统配件
机器人系统配件
大型伺服系统配件
品牌:ABB ,AB ,GE,FOXBORO,本特利,英维思,伍德沃德,西屋,瑞恩,施耐德,西门子,摩托罗拉,安川。力士乐。ACSO,横河等进口品牌。 专业销售进口DCS PLC系统备件模块
Triconex Siemens Yaskawa ABB GE Ovation AB Foxboro Motorola Schneider XYCOM KUKA 专业销售进口DCS PLC系统备件模块 15天包退换 一年质保 大量现货 国内实力库存商家
Water Quality Test Equipment , Tox-Array 2001 ,Foxboro
CLM253, CPM253 ,131VC-3t, GJL36015M03 ,Mil Ram
4 Tickets New England Patriots 12/24/11 Gillette Stadiu
Expedited shipping available
4 TIXs 6/26 Taylor Swift PIT Gillette Stadium
4 TIXs 6/25 Taylor Swift 114 Gillette Stadium
4 TIXs 6/25 Taylor Swift A4 Gillette Stadium
FOXBORO 2AX+TIM NSFP 2AXTIM
4 TIXs 6/25 Taylor Swift 133 Gillette Stadium
New England Patriots 4 home games and Preseason 4 seats
Expedited shipping available
FOXBORO D0134AB USPP D0134AB
4 TIXs Kenny Chesney & Zac Brown Band 8/28 Gillette
Expedited shipping available
4 TIXs Kenny Chesney & Zac Brown Band 8/27 Gillette
Expedited shipping available
FOXBORO 111-A USPP 111A
Foxboro Pressure Transmitter IDP10-DS1B01C-M1L1C1K1
FOXBORO 136-2 NSFP 1362
FOXBORO 136-7-11 NSFP 136711
FOXBORO Q0106KN NSPP Q0106KN
8 TIX US Mens National Soccer Team 108 6/4 Gillette
One-day shipping available
FOXBORO 2AX-SQE NSFP 2AXSQE
FOXBORO 12A NSFP 12A
FOXBORO 12A-75-200C NSFP 12A75200C
FOXBORO 235SJ-V NSFP 235SJV
FOXBORO 43AP-FA42D/PC USPP 43APFA42DPC
FOXBORO CFT10-PAENFNS USPP CFT10PAENFNS
FOXBORO 202S-10-SSSSSNSNSS USPP 202S10SSSSSNSNSS
Foxboro Miran 1BX Ambient Air Analyzer untested
FOXBORO 130M-N4 USPP 130MN4
New in box FOXBORO SUMMER 2AX+SUM STD 2AXSUM
FOXBORO 202S-04-SSSS USPP 202S04SSSS
FOXBORO PEPPERL FUCHS FBM201 ISTA-201-ZB87F UNIT 99122
FOXBORO PEPPERL FUCHS FBM204 ISTA-204-ZB87F UNIT 99134
FOXBORO PEPPERL FUCHS FBM206 ISTA-206-ZB87F UNIT 107187
2 NEW ENGLAND PATRIOTS vs Kansas CHIEFS Tickets 11/21
Expedited shipping available
2 NEW ENGLAND PATRIOTS vs Miami DOLPHINS Tickets 12/24
Expedited shipping available
TAYLOR SWIFT TICKETS GILLETTE STADIUM Foxborough MA
2 FLOOR TICKETS TOGETHER – 4 ROWS FROM STAGE – A2 ROW 4
One-day shipping available
Enlarge
2″ FOXBORO MAGNETIC FLOW METER – NIB
FOXBORO P0400DA FBM01 0-20mA Input NIB Free Ship
4 Tickets New England Patriots Green Bay Packers
LOWER LEVEL ENDZONE!!
Expedited shipping available
FOXBORO DCS Communication Card P0971WV
2 Zone B1 Tickets (10/9) New England Patriots vs Jets
FOXBORO L0111KU-A USPP L0111KUA
FOXBORO D0139NZ USPP D0139NZ
FOXBORO 99D250 USPP 99D250
4 Tickets New England Patriots Cowboys 10/16/11 Gillet
FOXBORO 280H-SBBA-TSA-G USPP 280HSBBATSAG
FOXBORO 760CSA-2A USPP 760CSA2A
FOXBORO A7000FS USPP A7000FS
FOXBORO P0902DZ USPP P0902DZ
5 TIXs 6/25 Taylor Swift PIT GA Gillette Stadium
FOXBORO 2DRPS25-A6 NSFP 2DRPS25A6
FOXBORO 235SK-LV NSFP 235SKLV
4 Tickets New England Patriots Jets 10/9/11 Gillette S
One-day shipping available
FOXBORO P0911YY USPP P0911YY
3 Zone D2 Tickets (10/9) New England Patriots vs Jets
FOXBORO B0142DR NSPP B0142DR
4 TIXs 6/25 Taylor Swift 130 Gillette Stadium
4 TIXs 6/26 Taylor Swift PIT Gillette Stadium
4 TIXs 6/26 Taylor Swift PIT Gillette Stadium
4 TIXs 6/26 Taylor Swift 130 Gillette Stadium
FOXBORO 130PD-N USPP 130PDN
FOXBORO P0400YE USPP P0400YE
4 Tickets New England Revolution United 7/13/11 Gillet
4 Tickets New England Patriots 1/1/12 Gillette Stadium
Expedited shipping available
2 Tickets New England Patriots Cowboys 10/16/11 Gillet
FOXBORO 2AX+TIM NSPP 2AXTIM
FOXBORO 3AX+LP1-M1 USPP 3AXLP1M1
FOXBORO 2AX-A2 NSFP 2AXA2
FOXBORO 2AX-A4 NSFP 2AXA4
Foxboro Flowmeter 8304-SABA-TSJ-GCGZ-G
FOXBORO CM400YK-0A USPP CM400YK0A
FOXBORO 130MD-N USPP 130MDN
4 Tickets New England Patriots Cowboys 10/16/11 Gillet
One-day shipping available
FOXBORO 235SB USPP 235SB
FOXBORO D0140JE USPP D0140JE
4 Tickets New England Patriots Cowboys 10/16/11 Gillet
FOXBORO 136-4-1 NSPP 13641
FOXBORO 136-4-3 NSPP 13643
2 Tickets Kenny Chesney 8/27/11 Gillette Stadium
One-day shipping available
2 Tickets Kenny Chesney & Zac Brown Band 8/28/11 Gillet
One-day shipping available
Foxboro 2800 Series magnetic flow tube meter 1 1/2 pipe
2″ Foxboro I/A Series Mass Flowmeter System
CFS10-20CPCGZ
2 NEW ENGLAND PATRIOTS vs Dallas COWBOYS Tickets 10/16
Expedited shipping available
2 NEW ENGLAND PATRIOTS vs Buffalo BILLS Tickets 1/1/12
Expedited shipping available
Foxboro Digital Circular Chart Recorder 740RA-A3000ACN
4 Tickets New England Patriots Chargers 9/18/11 Gillet
One-day shipping available
FOXBORO 2AX-SQE NSPP 2AXSQE
FOXBORO 12A-0-60C NSPP 12A060C
4 TAYLOR SWIFT TICKETS 6/26 GILLETTE, MA – SECTION A4
Expedited shipping available
FOXBORO 135S USPP 135S
FOXBORO 135S-C-L USPP 135SCL
FOXBORO 2AX-A5 NSPP 2AXA5
4 Tickets New England Patriots Giants 11/6/11 Gillette
One-day shipping available
2 Tickets Kenny Chesney & Zac Brown Band 8/27/11 Gillet
FOXBORO P0970EJ NSFP P0970EJ
FOXBORO 3F8-R2DPA1 USPP 3F8R2DPA1
Foxboro Vortex Flowmeter 6″ 83F-D06K1SSTJA
2 Zone A1 Tickets (10/9) New England Patriots vs Jets
FOXBORO P0400DA-0K NSFP P0400DA0K
FOXBORO G0113ES USPP G0113ES
FOXBORO 2AT-SBU USPP 2ATSBU
FOXBORO P0400QL USPP P0400QL
FOXBORO P0400YC USPP P0400YC
4 Tickets New England Patriots Bills 1/1/12 Gillette S
4 Tickets New England Patriots Cowboys 10/16/11 Gillet
4 Tickets New England Patriots Giants 11/6/11 Gillette
4 Tickets New England Patriots Colts 12/4/11 Gillette
4 Tickets New England Patriots Dolphins 12/24/11 Gille
4 Tickets New England Patriots Chiefs 11/21/11 Gillett
Foxboro I/A P0904AJ Table Top GCIO W/TS P0904 AJ
Foxboro I/A P0911VW MIW GCIO W/TS WP20/30 P0911 VW
FOXBORO 227S-3R6 NSFP 227S3R6
FOXBORO F0100AK-B USPP F0100AKB
FOXBORO A2049ELH USPP A2049ELH
Foxboro FBM2 Thermocouple/mV Input Module P0400YC
FOXBORO 112 NSFP 112
FOXBORO 230SM-T USPP 230SMT
3 Zone F Tickets (10/9) New England Patriots vs Jets
4 Tickets New England Patriots Cowboys 10/16/11 Gillet
4 Tickets New England Patriots Cowboys 10/16/11 Gillet
FOXBORO B0142DR USPP B0142DR
5 TIXs 6/26 Taylor Swift CLUB 34 Gillette Stadium
2 TIXs 6/25 Taylor Swift B5 Gillette Stadium
4 TIXs 6/26 Taylor Swift 130 Gillette Stadium
FOXBORO 135T-W/102-NO NSFP 135TW102NO
FOXBORO P0922KS USPP P0922KS
FOXBORO A2049WW USPP A2049WW
2 TIXs 6/25 Taylor Swift A2 Gillette Stadium
4 TIXs 6/26 Taylor Swift A4 Gillette Stadium
FOXBORO 230SF USPP 230SF
4 TAYLOR SWIFT TICKETS 6/26 GILLETTE, MA – SECTION A2
Expedited shipping available
FOXBORO P0904BR USPP P0904BR
FOXBORO 2AX-MUL USPP 2AXMUL
FOXBORO 130FD-N-C-L USPP 130FDNCL
FOXBORO 130FD-N USPP 130FDN
6 Tickets New England Patriots Miami Dolphins
CHEEEEEEEAP
Kenny Chesney SANDBAR Tickets 8/28/11 (Foxboro)
FOXBORO M/2800 MAGNETIC FLOW TUBE 2B03-SABA-TPA-G
17 TIX New England Revolution v Manchester United 224
One-day shipping available
FOXBORO FIELD STATION 743CB-AP MICRO CONTROLLER
FOXBORO FBM03 Module P0400YD NIB
10″ Foxboro Teflon Lined Flowmeter NEW
2 NEW ENGLAND PATRIOTS vs CHARGERS Tickets 9/18
Expedited shipping available
2 Taylor Swift Tickets 6/26 Gillette Stadium
2 Taylor Swift Tickets 6/26 Gillette Stadium
4 Zone F Tickets (10/9) New England Patriots vs Jets
FOXBORO 230SM-A USPP 230SMA
4 Tickets Kenny Chesney & Zac Brown Band 8/27/11 Gillet
One-day shipping available
4 Tickets New England Patriots Dolphins 12/24/11 Gille
4 Tickets New England Patriots Chiefs 11/21/11 Gillett
FOXBORO 2AI-P2V-FGB USPP 2AIP2VFGB
FOXBORO 2AI-T2V USPP 2AIT2V
FOXBORO 2AI-T2V-FGB USPP 2AIT2VFGB
FOXBORO 2AX-SUM NSPP 2AXSUM
FOXBORO SANITARY VORTEX FLOW METER MODEL-835-T03TJA
FOXBORO 130PD-N NSFP 130PDN
FOXBORO D0140FT USPP D0140FT
1-6 TIX Taylor Swift 6/26 Gillette Stadium
One-day shipping available
FOXBORO A2047VS USPP A2047VS
4 Tickets New England Patriots 11/21/11 Gillette Stadiu
Expedited shipping available
FOXBORO D0143SK USPP D0143SK
FOXBORO 2AX-T2 NSFP 2AXT2
FOXBORO B0183AC USPP B0183AC
FOXBORO 202S-10-SSSFSNSNSSN USPP 202S10SSSFSNSNSS
FOXBORO P0972PP NSFP P0972PP
FOXBORO 230SE USPP 230SE
4 Tickets New England Patriots Cowboys 10/16/11 Gillet
One-day shipping available
4 Tickets New England Patriots Cowboys 10/16/11 Gillet
One-day shipping available
FOXBORO D0147KE USPP D0147KE
FOXBORO 13A-VS1 NSPP 13AVS1
FOXBORO 130K-N5-ECRB USPP 130KN5ECRB
FOXBORO P0913ED USPP P0913ED
6 Zone J Tickets (10/9) New England Patriots vs Jets
Foxboro Dual Nodebus Module P0971WV DNBT
3 Tickets New England Patriots Cowboys 10/16/11 Gillet
One-day shipping available
4 Tickets New England Revolution United 7/13/11 Gillet
4 Tickets New England Revolution United 7/13/11 Gillet
FOXBORO 135S NSFP 135S
FOXBORO 135S-C-L NSFP 135SCL
4 TIXs 6/26 Taylor Swift PIT GA Gillette Stadium
FOXBORO 230SM-S-A USPP 230SMSA
FOXBORO 202S-04-XXXX USPP 202S04XXXX
Foxboro Pressure Transmitter IDP10-DS1B01C-SK3FBR4M1L1T
FOXBORO 2026-04-SSSS USPP 202604SSSS
Foxboro Pressure Transmitter IDP10-DS1B01C
4 Tickets New England Patriots Bills 1/1/12 Gillette S
FOXBORO 202S-07-SSSFSSESNF USPP 202S07SSSFSSESNF
4 Tickets New England Patriots Colts 12/4/11 Gillette
One-day shipping available
4 Tickets New England Patriots Giants 11/6/11 Gillette
One-day shipping available
4 Tickets New England Patriots Colts 12/4/11 Gillette
One-day shipping available
4 Tickets New England Patriots Giants 11/6/11 Gillette
One-day shipping available
FOXBORO 2AT-SBU NSFP 2ATSBU
FOXBORO 111-A-L USPP 111AL
4 Tickets New England Patriots Chiefs 11/21/11 Gillett
Foxboro E96S-IA Magnetic Flow Transmitter E96SIA NEW
One-day shipping available
FOXBORO 2AX-SUM USPP 2AXSUM
4 TAYLOR SWIFT TICKETS 6/25 GILLETTE, MA – PIT GA
Expedited shipping available
FOXBORO 130PD-N NSPP 130PDN
Foxboro LCD Replacement for VS IV 13″ Monitor
Foxboro Replacement UCM Power Supply, 120VAC
Water Quality Test Equipment , Tox-Array 2001 ,Foxboro
CLM253, CPM253 ,131VC-3t, GJL36015M03 ,Mil Ram
4 Tickets New England Patriots 12/24/11 Gillette Stadiu
Expedited shipping available
4 TIXs 6/26 Taylor Swift PIT Gillette Stadium
4 TIXs 6/25 Taylor Swift 114 Gillette Stadium
4 TIXs 6/25 Taylor Swift A4 Gillette Stadium
FOXBORO 2AX+TIM NSFP 2AXTIM
4 TIXs 6/25 Taylor Swift 133 Gillette Stadium
New England Patriots 4 home games and Preseason 4 seats
Expedited shipping available
FOXBORO D0134AB USPP D0134AB
4 TIXs Kenny Chesney & Zac Brown Band 8/28 Gillette
Expedited shipping available
4 TIXs Kenny Chesney & Zac Brown Band 8/27 Gillette
Expedited shipping available
FOXBORO 111-A USPP 111A
Foxboro Pressure Transmitter IDP10-DS1B01C-M1L1C1K1
FOXBORO 136-2 NSFP 1362
FOXBORO 136-7-11 NSFP 136711
FOXBORO Q0106KN NSPP Q0106KN
8 TIX US Mens National Soccer Team 108 6/4 Gillette
One-day shipping available
FOXBORO 2AX-SQE NSFP 2AXSQE
FOXBORO 12A NSFP 12A
FOXBORO 12A-75-200C NSFP 12A75200C
FOXBORO 235SJ-V NSFP 235SJV
FOXBORO 43AP-FA42D/PC USPP 43APFA42DPC
FOXBORO CFT10-PAENFNS USPP CFT10PAENFNS
FOXBORO 202S-10-SSSSSNSNSS USPP 202S10SSSSSNSNSS
Foxboro Miran 1BX Ambient Air Analyzer untested
FOXBORO 130M-N4 USPP 130MN4
New in box FOXBORO SUMMER 2AX+SUM STD 2AXSUM
FOXBORO 202S-04-SSSS USPP 202S04SSSS
FOXBORO PEPPERL FUCHS FBM201 ISTA-201-ZB87F UNIT 99122
FOXBORO PEPPERL FUCHS FBM204 ISTA-204-ZB87F UNIT 99134
FOXBORO PEPPERL FUCHS FBM206 ISTA-206-ZB87F UNIT 107187
2 NEW ENGLAND PATRIOTS vs Kansas CHIEFS Tickets 11/21
Expedited shipping available
2 NEW ENGLAND PATRIOTS vs Miami DOLPHINS Tickets 12/24
Expedited shipping available
TAYLOR SWIFT TICKETS GILLETTE STADIUM Foxborough MA
2 FLOOR TICKETS TOGETHER – 4 ROWS FROM STAGE – A2 ROW 4
One-day shipping available
Enlarge
2″ FOXBORO MAGNETIC FLOW METER – NIB
FOXBORO P0400DA FBM01 0-20mA Input NIB Free Ship
4 Tickets New England Patriots Green Bay Packers
LOWER LEVEL ENDZONE!!
Expedited shipping available
FOXBORO DCS Communication Card P0971WV
2 Zone B1 Tickets (10/9) New England Patriots vs Jets
FOXBORO L0111KU-A USPP L0111KUA
FOXBORO D0139NZ USPP D0139NZ
FOXBORO 99D250 USPP 99D250
4 Tickets New England Patriots Cowboys 10/16/11 Gillet
FOXBORO 280H-SBBA-TSA-G USPP 280HSBBATSAG
FOXBORO 760CSA-2A USPP 760CSA2A
FOXBORO A7000FS USPP A7000FS
FOXBORO P0902DZ USPP P0902DZ
5 TIXs 6/25 Taylor Swift PIT GA Gillette Stadium
FOXBORO 2DRPS25-A6 NSFP 2DRPS25A6
FOXBORO 235SK-LV NSFP 235SKLV
4 Tickets New England Patriots Jets 10/9/11 Gillette S
One-day shipping available
FOXBORO P0911YY USPP P0911YY
3 Zone D2 Tickets (10/9) New England Patriots vs Jets
FOXBORO B0142DR NSPP B0142DR
4 TIXs 6/25 Taylor Swift 130 Gillette Stadium
4 TIXs 6/26 Taylor Swift PIT Gillette Stadium
4 TIXs 6/26 Taylor Swift PIT Gillette Stadium
4 TIXs 6/26 Taylor Swift 130 Gillette Stadium
FOXBORO 130PD-N USPP 130PDN
FOXBORO P0400YE USPP P0400YE
4 Tickets New England Revolution United 7/13/11 Gillet
4 Tickets New England Patriots 1/1/12 Gillette Stadium
Expedited shipping available
2 Tickets New England Patriots Cowboys 10/16/11 Gillet
FOXBORO 2AX+TIM NSPP 2AXTIM
FOXBORO 3AX+LP1-M1 USPP 3AXLP1M1
FOXBORO 2AX-A2 NSFP 2AXA2
FOXBORO 2AX-A4 NSFP 2AXA4
Foxboro Flowmeter 8304-SABA-TSJ-GCGZ-G
FOXBORO CM400YK-0A USPP CM400YK0A
FOXBORO 130MD-N USPP 130MDN
4 Tickets New England Patriots Cowboys 10/16/11 Gillet
PLC模块,可编程控制器,CPU模块,IO模块,AI模块,通讯模块。AB/施耐德/ABB/GE/本特利/西屋/英维斯/霍尼韦尔/黑马/FU克斯波罗
15天包退换 一年质保 大量现货 国内实力库存商家