关于PCB封装的资料收集整理. 大的来说,元件有插装和贴装.零件封装是指实际零件焊接到电路板时所指示的外观和焊点的位置。是纯粹的空间概念.因此不同的元件可共用同一零件封装,同种元件也可有不同的零件封装。像电阻,有传统的针插式,这种元件体积较大,电路板必须钻孔才能安置元件,完成钻孔后,插入元件,再过锡炉或喷锡(也可手焊),成本较高,较新的设计都是采用体积小的表面贴片式元件(SMD)这种元件不必钻孔,用钢膜将半熔状锡膏倒入电路板,再把SMD 元件放上,即可焊接在电路板上了。晶体管是我们常用的的元件之一,在DEVICE。LIB库中,简简单单的只有NPN与PNP之分,但实际上,如果它是NPN的2N3055那它有可能是铁壳子的TO—3,如果它是NPN的2N3054,则有可能是铁壳的TO-66或TO-5,而学用的CS9013,有TO-92A,TO-92B,还有TO-5,TO-46,TO-52等等,千变万化。还有一个就是电阻,在DEVICE 库中,它也是简单地把它们称为RES1 和RES2,不管它是100Ω 还是470KΩ都一样,对电路板而言,它与欧姆数根本不相关,完全是按该电阻的功率数来决定的我们选用的1/4W 和甚至1/2W 的电阻,都可以用AXIAL0.3 元件封装,而功率数大一点的话,可用AXIAL0.4,AXIAL0.5等等。现将常用的元件封装整理如下:电阻类及无极性双端元件:AXIAL0.3-AXIAL1.0无极性电容:RAD0.1-RAD0.4有极性电容:RB.2/.4-RB.5/1.0二极管:DIODE0.4及DIODE0.7石英晶体振荡器:XTAL1晶体管、FET、UJT:TO-xxx(TO-3,TO-5)可变电阻(POT1、POT2):VR1-VR5这些常用的元件封装,大家最好能把它背下来,这些元件封装,大家可以把它拆分成两部分来记如电阻AXIAL0.3 可拆成AXIAL 和0.3,AXIAL 翻译成中文就是轴状的,0.3 则是该电阻在印刷电路板上的焊盘间的距离也就是300mil(因为在电机领域里,是以英制单位为主的。同样的,对于无极性的电容,RAD0.1-RAD0.4也是一样;对有极性的电容如电解电容,其封装为RB.2/.4,RB.3/.6 等,其中“.2”为焊盘间距,“.4”为电容圆筒的外径。对于晶体管,那就直接看它的外形及功率,大功率的晶体管,就用TO—3,中功率的晶体管,如果是扁平的,就用TO-220,如果是金属壳的,就用TO-66,小功率的晶体管,就用TO-5,TO-46,TO-92A等都可以,反正它的管脚也长,弯一下也可以。对于常用的集成IC电路,有DIPxx,就是双列直插的元件封装,DIP8就是双排,每排有4个引脚,两排间距离是300mil,焊盘间的距离是100mil。SIPxx 就是单排的封装。等等。值得我们注意的是晶体管与可变电阻,它们的包装才是最令人头痛的,同样的包装,其管脚可不一定一样。例如,对于TO-92B之类的包装,通常是1 脚为E(发射极),而2 脚有可能是B 极(基极),也可能是C(集电极);同样的,3脚有可能是C,也有可能是B,具体是那个,只有拿到了元件才能确定。因此,电路软件不敢硬性定义焊盘名称(管脚名称),同样的,场效应管,MOS 管也可以用跟晶体管一样的封装,它可以通用于三个引脚的元件。Q1-B,在PCB 里,加载这种网络表的时候,就会找不到节点(对不上)。在可变电阻
上传时间: 2013-11-03
上传用户:daguogai
The CAT25128 is a 128−Kb Serial CMOS EEPROM device internally organized as 16Kx8 bits. This features a 64−byte page write buffer and supports the Serial Peripheral Interface (SPI) protocol. The device is enabled through a Chip Select (CS) input. In addition, the required bus signals are clock input (SCK), data input (SI) and data output (SO) lines. The HOLD input may be used to pause any serial communication with the CAT25128 device. The device featuressoftware and hardware write protection, including partial as well as full array protection.
上传时间: 2013-11-15
上传用户:fklinran
The CAT823, CAT824, and CAT825 provide basic reset and monitoring functions for the electronic systems. Each device monitors the system voltage and maintains a reset output until that voltage reaches the device’s specified trip value and then maintains the reset output active condition until the device’s internal timer, after a minimum timer of 140ms; toallow the systems power supply to stabilize.
上传时间: 2014-11-18
上传用户:BOBOniu
The PAM2862 is a continuous mode inductivestep-down converter, designed for driving singleor multiple series connected LEDs efficientlyfrom a voltage source higher than the LEDvoltage. The device operates from an inputupply between 6V and 30V and provides anexternally adjustable output current of up to 1A.Depending upon supply voltage and externalcomponents, this can provide up to 24 watts ofoutput power.
上传时间: 2013-11-16
上传用户:司令部正军级
The PCA9534 is a 16-pin CMOS device that provide 8 bits of General Purpose parallel Input/Output (GPIO) expansion for I2C-bus/SMBus applications and was developed to enhance the NXP Semiconductors family of I2C-bus I/O expanders. The improvements include higher drive capability, 5 V I/O tolerance, lower supply current, individual I/O configuration, 400 kHz clock frequency, and smaller packaging. I/O expanders provide a simple solution when additional I/O is needed for ACPI power switches, sensors, push buttons, LEDs, fans, etc.
上传时间: 2013-10-10
上传用户:inwins
The PCA9536 is an 8-pin CMOS device that provides 4 bits of General Purpose parallelInput/Output (GPIO) expansion for I2C-bus/SMBus applications and was developed toenhance the NXP Semiconductors family of I2C-bus I/O expanders. I/O expanders providea simple solution when additional I/O is needed for ACPI power switches, sensors,push buttons, LEDs, fans, etc.
上传时间: 2013-10-09
上传用户:731140412
The PCA9537 is a 10-pin CMOS device that provides 4 bits of General Purpose parallelInput/Output (GPIO) expansion with interrupt and reset for I2C-bus/SMBus applicationsand was developed to enhance the NXP Semiconductors family of I2C-bus I/O expanders.I/O expanders provide a simple solution when additional I/O is needed for ACPI powerswitches, sensors, push-buttons, LEDs, fans, etc.
上传时间: 2013-10-14
上传用户:wuchunzhong
<Almost since the introduction of microcontrollers as electronic components there always has been an oscillatorcircuit on the device to make it work. From application point of view only some external components wererequired to make it work. However, to make sure that it will always work required more effort. This report is basedon feedback from the market from customers applying 8-bit mircrocontrollers.>
标签: oscillators X-tal bit mic
上传时间: 2013-11-12
上传用户:穿着衣服的大卫
The PCA9538 is a 16-pin CMOS device that provides 8 bits of General Purpose parallelInput/Output (GPIO) expansion with interrupt and reset for I2C-bus/SMBus applicationsand was developed to enhance the NXP Semiconductors family of I2C-bus I/O expanders.I/O expanders provide a simple solution when additional I/O is needed for ACPI powerswitches, sensors, push-buttons, LEDs, fans, etc.
上传时间: 2014-01-24
上传用户:youmo81
The PCA9539; PCA9539R is a 24-pin CMOS device that provides 16 bits of GeneralPurpose parallel Input/Output (GPIO) expansion with interrupt and reset forI2C-bus/SMBus applications and was developed to enhance the NXP Semiconductorsfamily of I2C-bus I/O expanders. I/O expanders provide a simple solution when additionalI/O is needed for ACPI power switches, sensors, push buttons, LEDs, fans, etc.
上传时间: 2013-11-10
上传用户:ewtrwrtwe