PCB LAYOUT 術語解釋(TERMS)1. COMPONENT SIDE(零件面、正面)︰大多數零件放置之面。2. SOLDER SIDE(焊錫面、反面)。3. SOLDER MASK(止焊膜面)︰通常指Solder Mask Open 之意。4. TOP PAD︰在零件面上所設計之零件腳PAD,不管是否鑽孔、電鍍。5. BOTTOM PAD:在銲錫面上所設計之零件腳PAD,不管是否鑽孔、電鍍。6. POSITIVE LAYER:單、雙層板之各層線路;多層板之上、下兩層線路及內層走線皆屬之。7. NEGATIVE LAYER:通常指多層板之電源層。8. INNER PAD:多層板之POSITIVE LAYER 內層PAD。9. ANTI-PAD:多層板之NEGATIVE LAYER 上所使用之絕緣範圍,不與零件腳相接。10. THERMAL PAD:多層板內NEGATIVE LAYER 上必須零件腳時所使用之PAD,一般稱為散熱孔或導通孔。11. PAD (銲墊):除了SMD PAD 外,其他PAD 之TOP PAD、BOTTOM PAD 及INNER PAD 之形狀大小皆應相同。12. Moat : 不同信號的 Power& GND plane 之間的分隔線13. Grid : 佈線時的走線格點2. Test Point : ATE 測試點供工廠ICT 測試治具使用ICT 測試點 LAYOUT 注意事項:PCB 的每條TRACE 都要有一個作為測試用之TEST PAD(測試點),其原則如下:1. 一般測試點大小均為30-35mil,元件分布較密時,測試點最小可至30mil.測試點與元件PAD 的距離最小為40mil。2. 測試點與測試點間的間距最小為50-75mil,一般使用75mil。密度高時可使用50mil,3. 測試點必須均勻分佈於PCB 上,避免測試時造成板面受力不均。4. 多層板必須透過貫穿孔(VIA)將測試點留於錫爐著錫面上(Solder Side)。5. 測試點必需放至於Bottom Layer6. 輸出test point report(.asc 檔案powerpcb v3.5)供廠商分析可測率7. 測試點設置處:Setuppadsstacks
上传时间: 2013-10-22
上传用户:pei5
Boost LED drivers are often used to drive LEDs in series. If an LED fails while open,overvoltage protection (OVP) is necessary to avoid the damage to a boost integrated circuit (IC) or output capacitor. This application report presents the solutions to increase the TPS61043 LED driver OVP threshold.
标签: Overvoltage Protection Solutions Driver
上传时间: 2013-10-14
上传用户:jiangfire
返驰式(Flyback) 电源供应器是交换式电源设计供应器(Switch Power Supply,SPS)的一种,为工业界常用之电路架构,其特点如下表所示,图一所示为返驰式转换器(Flyback Converter)电路。 一般设计SPS需要一些保护来提高系统设备之稳定安全,尤其是输出过电压保护极为重要,这个输出过电压保护目的是防止电气设备上的元件之绝缘遭受过电压的破坏。一般过电压的测试方法是将回授Open让系统呈现段回路状况,导致一次侧能量无限制提供给二次测来达到输出过电压现象。
上传时间: 2013-11-06
上传用户:haoxiyizhong
Abstract: Stuxnet, a sophisticated virus that damaged Iran's nuclear capability, should be an eye openerfor the world. We can choose to learn something very narrow (how to combat the Stuxnet virus) or wecan choose to focus on the larger goal of thwarting the next type of creative cyber attack. Unfortunately,critical industrial infrastructure is not currently designed with security as a key goal, leaving open multipleavenues for an educated and funded attacker to create massive problems. This tutorial outlines somebasic concepts that engineers and product definers should consider to make sure their new projects stayahead of future threats.
上传时间: 2013-11-17
上传用户:llwap
交流瓦特/瓦特小时,乏尔/乏尔小时转换器 特点: 精确度0.25%满刻度 多种输入,输出选择 输入与输出绝缘耐压2仟伏特/1分钟 冲击电压测试5仟伏特(1.2x50us) 突波电压测试2.5仟伏特(0.25ms/1MHz) (IEC255-4) 尺寸小,稳定性高 主要规格: 精确度: 0.25% F.S. (23 ±5℃) 输入负载: <0.2VA (Voltage) <0.2VA (Current) 最大过载能力: Current related input:3 x rated continuous 10 x rated 30 sec. ,25 x rated 3sec. 50 x rated 1sec. Voltage related input:maximum 2 x rated continuous 输出反应速度: < 250ms(0~90%) 输出负载能力: < 10mA for voltage mode < 10V for current mode 输出之涟波 : < 0.1% F.S. 脉波输出型态: Photocouple of open collector (max.30V/40mA) 归零调整范围: 0~±5% F.S. 最大值调整范围: 0~±10% F.S. 温度系数: 100ppm/℃ (0~50℃) 隔离特性: Input/Output/Power/Case 绝缘阻抗: >100Mohm with 500V DC 绝缘耐压能力: 2KVac/1 min. (input/output/power/case) 突波测试: ANSI C37.90a/1974,DIN-IEC 255-4 impulse voltage 5KV(1.2x50us) 使用环境条件: -20~60℃(20 to 90% RH non-condensed) 存放环境条件: -30~70℃(20 to 90% RH non-condensed) CE认证: EN 55022:1998/A1:2000 Class A EN 61000-3-2:2000 EN 61000-3-3:1995/A1:2001 EN 55024:1998/A1:2001
上传时间: 2013-11-11
上传用户:wettetw
This ink marks LTC’s eighth circuit collection publication.1We are continually surprised, to the point of near mystification, by these circuit amalgams seemingly limitlessappeal. Reader requests ascend rapidly upon publication,remaining high for years, even decades. All LTC circuitcollections, despite diverse content, share this popularity,although just why remains an open question. Why isit? Perhaps the form; compact, complete, succinct andinsular. Perhaps the freedom of selection without commitment,akin to window shopping.
上传时间: 2014-01-06
上传用户:ligi201200
STM32,5110液晶显示声纳探鱼器200KHz,带电路图,精确到厘米 MC34063升压,大声压发射,实际板子上滤波电路没要(电路图上的滤波电阻电容电感没焊,开路或者短路)。一般200KHz的换能器在水里面的耦合比较好,在空气中发射出来的(或者接收的)强度很低。 用的MOSFET Relay,contact和release时间都可以做到很小,不过选的是比较低端器件,所以最近测量距离为70cm。 开源啦开源啦 架构为状态机+任务流,Task都是放在函数指针数组里面的 Task分两种,routine的和错误处理的 5110液晶的SPI用的DMA 基本上STM32和C语言高阶的特征都用上了,稍微修改直接可以商用 Open Issue 偶尔会hardware fault或者memory fault,然后watchdog重启, 应该比较好解决,仔细检查下就好 有什么问题代码的file comment里面有我联系地址 有能搞到好的器件也请知会我,多谢了 接下来准备把它装到船模上,用以前四轴的那套东西,就看什么时候有时间了
上传时间: 2013-10-28
上传用户:songyue1991
在开放式数控系统结构模型的基础上,研究了基于ISA总线的DSP通信控制原理。采用中断方式完成了PC机和DSP之间的通信。介绍了以DriverWorks为工具开发ISA设备WDM驱动程序的方法,探讨了中断处理、驱动程序与应用程序之间的通信,简要说明了驱动程序的安装与调试。通过调试,系统设计运行稳定。 Abstract: The ISA bus and DSP correspondence control principle is investigated in the basis of the existing open architecture numerical control system.The interrupt method is used to realize the communication between PC and DSP based on the ISA bus.The methods of WDM driver exploitation for ISA device using Driver Works are introduced.The main process of driver program and the keys such as handle interrupt and the communication between the drivers and application are presented.And how to debug and install the drive is explained.
上传时间: 2013-11-04
上传用户:kang1923
在汽车发动机起动时,若发动机起动后起动机不能及时断电,将会烧毁起动机或损坏飞轮齿环;若变速器不在空档位置起动,则起动机的瞬间动力将使汽车位移,还可能引起交通事故和人身安全。为此介绍一种利用NXP P89LPC901单片机控制的汽车起动保护控制器,通过检测汽车起动开关、变速箱档位、发动机转速,实现对汽车发动机起动过程检测和保护。起动保护控制器在发动机起动过程中通过采用逐个关闭打开负载系统,解决汽车发动机过程中因起动电流大而对汽车电源的冲击影响,延长了电瓶寿命。 Abstract: When the automotive engine is started, the engine start motor and flywheel gear may be damaged, even traffic accidents and personal safeties may be caused by wrong operation or other factors.In order to ensure the automotive engine can be started normally and safely,it is necessary that the protecting measures and methods are considered in the automotive electrical control system.This paper introduces a kind of the automotive engine starting protect controller based on NXP P89LPC901 MCU.The controller can protect the engine starting process by detecting the starter key switch,transmission stall and engine speed.Through the use of close and open load system,the controller can solve the impact on automotive power because of the high-current load in the process of the automobile engine starting, and extend battery life.
上传时间: 2013-10-15
上传用户:mikesering
The PCA9544A provides 4 interrupt inputs, one for each channeland one open drain interrupt output. When an interrupt is generated byany device, it will be detected by the PCA9544A and the interruptoutput will be driven LOW. The channel need not be active fordetection of the interrupt. A bit is also set in the control byte.Bits 4 – 7 of the control byte correspond to channels 0 – 3 of thePCA9544A, respectively. Therefore, if an interrupt is generated byany device connected to channel 2, the state of the interrupt inputs isloaded into the control register when a read is accomplished.Likewise, an interrupt on any device connected to channel 0 wouldcause bit 4 of the control register to be set on the read. The mastercan then address the PCA9544A and read the contents of thecontrol byte to determine which channel contains the devicegenerating the interrupt. The master can then reconfigure thePCA9544A to select this channel, and locate the device generatingthe interrupt and clear it. The interrupt clears when the deviceoriginating the interrupt clears.
标签: 4channel multiple 9544A 9544
上传时间: 2014-12-28
上传用户:潜水的三贡