高的工作电压高达100V N双N沟道MOSFET同步驱动 The D810DCDC is a synchronous step-down switching regulator controller that can directly step-down voltages from up to 100V, making it ideal for telecom and automotive applications. The D810DCDC uses a constant on-time valley current control architecture to deliver very low duty cycles with accurate cycle-by-cycle current limit, without requiring a sense resistor. A precise internal reference provides 0.5% DC accuracy. A high bandwidth (25MHz) error amplifi er provides very fast line and load transient response. Large 1Ω gate drivers allow the D810DCDC to drive multiple MOSFETs for higher current applications. The operating frequency is selected by an external resistor and is compensated for variations in VIN and can also be synchronized to an external clock for switching-noise sensitive applications. Integrated bias control generates gate drive power from the input supply during start-up and when an output shortcircuit occurs, with the addition of a small external SOT23 MOSFET. When in regulation, power is derived from the output for higher effi ciency.
上传时间: 2013-10-24
上传用户:wd450412225
DC/DC 升压IC:The FP6291 is a current mode boost DC-DC converter. Its PWM circuitry with built-in 0.25 Ω power MOSFET make this regulator highly power efficient. The internal compensation network also minimizes as much as 6 external component counts. The non-inverting input of error amplifier connects to a 0.6V precision reference voltage and internal soft-start function can reduce the inrush current. The FP6291 is available in the SOT23-6L package and provides space-saving PCB for the application fields.
上传时间: 2013-11-07
上传用户:3294322651
Industrial remote monitoring systems and keep-alivecircuits spend most of their time in standby mode. Manyof these systems also depend on battery power, so powersupply effi ciency in standby state is very important tomaximize battery life. The LT®8410/-1 high effi ciencyboost converter is ideal for these systems, requiringonly 8.5μA of quiescent current in standby mode. Thedevice integrates high value (12.4M/0.4M) output feedbackresistors, signifi cantly reducing input current whenthe output is in regulation with no load. Other featuresinclude an integrated 40V switch and Schottky diode,output disconnect with current limit, built in soft-start,overvoltage protection and a wide input range, all in atiny 8-pin 2mm × 2mm DFN package.
上传时间: 2013-11-23
上传用户:新手无忧
Arduino 一些资料
标签: Quick-Start Arduino Schmidt Guide
上传时间: 2013-11-07
上传用户:气温达上千万的
提出一种基于凌阳单片机的步进电机加减速的控制方法。采用凌阳科技推出的16位结构工控单片机SPMC75F2413A为控制器,由Allegro公司生产的两相步进电机专用驱动器件SLA7042M构成步进电机的驱动电路,在传统的3段直线加减速控制算法基础上增加至7段S形曲线加减速过程,控制步进电机的启动和停止。实验结果表明,该控制方法克服了直线加减速中不连续、易造成系统冲击的问题,整个系统实现柔性控制,电机启动、停止连续性能提高30%。 Abstract: The method of controlled stepping motor is referred based on SPMC75F2413A MCU, which adopts the 16 knots SPMC75F2413A MCU as the controller. The special-purpose actuation chip SLA7042M of two stepping motor produced by Allegro Corporation constituted to actuation electric circuit. The purpose of increasing to seven section of S shape curve based on the traditional three sections of straight line is to control the start and stop process of stepping motor. The experimental results show that the control method solves easy to pull-out and overshot problems. The overall system realizes flexible control, and the performance of motor start or stop continuity is increased 30%
上传时间: 2013-12-08
上传用户:jiangfire
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 MSP-FET430U14 is a powerful flash emulation tool to quickly begin application development on the MSP430 MCU. It includes USB debugging interface used to program and debug the MSP430 in-system through the JTAG interface or the pin saving Spy Bi-Wire (2-wire JTAG) protocol. The flash memory can be erased and programmed in seconds with only a few keystrokes, and since the MSP430 flash is ultra-low power, no external power supply is required. The debugging tool interfaces the MSP430 to the included integrated software environment and includes code to start your design immediately. The MSP-FET430UIF development tools supports development with all MSP430 flash devices
上传时间: 2013-10-28
上传用户:13691535575
The CAT28LV64 is a low voltage, low power, CMOS Parallel EEPROM organized as 8K x 8−bits. It requires a simple interface for in−system programming. On−chip address and data latches, self−timed write cycle with auto−clear and VCC power up/down write protection eliminate additional timing and protection hardware. DATA Polling and Toggle status bit signal the start and end of the self−timed write cycle. Additionally, the CAT28LV64 features hardware and software write protection.
上传时间: 2013-11-16
上传用户:浩子GG
PC机之间串口通信的实现一、实验目的 1.熟悉微机接口实验装置的结构和使用方法。 2.掌握通信接口芯片8251和8250的功能和使用方法。 3.学会串行通信程序的编制方法。 二、实验内容与要求 1.基本要求主机接收开关量输入的数据(二进制或十六进制),从键盘上按“传输”键(可自行定义),就将该数据通过8251A传输出去。终端接收后在显示器上显示数据。具体操作说明如下:(1)出现提示信息“start with R in the board!”,通过调整乒乓开关的状态,设置8位数据;(2)在小键盘上按“R”键,系统将此时乒乓开关的状态读入计算机I中,并显示出来,同时显示经串行通讯后,计算机II接收到的数据;(3)完成后,系统提示“do you want to send another data? Y/N”,根据用户需要,在键盘按下“Y”键,则重复步骤(1),进行另一数据的通讯;在键盘按除“Y”键外的任意键,将退出本程序。2.提高要求 能够进行出错处理,例如采用奇偶校验,出错重传或者采用接收方回传和发送方确认来保证发送和接收正确。 三、设计报告要求 1.设计目的和内容 2.总体设计 3.硬件设计:原理图(接线图)及简要说明 4.软件设计框图及程序清单5.设计结果和体会(包括遇到的问题及解决的方法) 四、8251A通用串行输入/输出接口芯片由于CPU与接口之间按并行方式传输,接口与外设之间按串行方式传输,因此,在串行接口中,必须要有“接收移位寄存器”(串→并)和“发送移位寄存器”(并→串)。能够完成上述“串←→并”转换功能的电路,通常称为“通用异步收发器”(UART:Universal Asynchronous Receiver and Transmitter),典型的芯片有:Intel 8250/8251。8251A异步工作方式:如果8251A编程为异步方式,在需要发送字符时,必须首先设置TXEN和CTS#为有效状态,TXEN(Transmitter Enable)是允许发送信号,是命令寄存器中的一位;CTS#(Clear To Send)是由外设发来的对CPU请求发送信号的响应信号。然后就开始发送过程。在发送时,每当CPU送往发送缓冲器一个字符,发送器自动为这个字符加上1个起始位,并且按照编程要求加上奇/偶校验位以及1个、1.5个或者2个停止位。串行数据以起始位开始,接着是最低有效数据位,最高有效位的后面是奇/偶校验位,然后是停止位。按位发送的数据是以发送时钟TXC的下降沿同步的,也就是说这些数据总是在发送时钟TXC的下降沿从8251A发出。数据传输的波特率取决于编程时指定的波特率因子,为发送器时钟频率的1、1/16或1/64。当波特率指定为16时,数据传输的波特率就是发送器时钟频率的1/16。CPU通过数据总线将数据送到8251A的数据输出缓冲寄存器以后,再传输到发送缓冲器,经移位寄存器移位,将并行数据变为串行数据,从TxD端送往外部设备。在8251A接收字符时,命令寄存器的接收允许位RxE(Receiver Enable)必须为1。8251A通过检测RxD引脚上的低电平来准备接收字符,在没有字符传送时RxD端为高电平。8251A不断地检测RxD引脚,从RxD端上检测到低电平以后,便认为是串行数据的起始位,并且启动接收控制电路中的一个计数器来进行计数,计数器的频率等于接收器时钟频率。计数器是作为接收器采样定时,当计数到相当于半个数位的传输时间时再次对RxD端进行采样,如果仍为低电平,则确认该数位是一个有效的起始位。若传输一个字符需要16个时钟,那么就是要在计数8个时钟后采样到低电平。之后,8251A每隔一个数位的传输时间对RxD端采样一次,依次确定串行数据位的值。串行数据位顺序进入接收移位寄存器,通过校验并除去停止位,变成并行数据以后通过内部数据总线送入接收缓冲器,此时发出有效状态的RxRDY信号通知CPU,通知CPU8251A已经收到一个有效的数据。一个字符对应的数据可以是5~8位。如果一个字符对应的数据不到8位,8251A会在移位转换成并行数据的时候,自动把他们的高位补成0。 五、系统总体设计方案根据系统设计的要求,对系统设计的总体方案进行论证分析如下:1.获取8位开关量可使用实验台上的8255A可编程并行接口芯片,因为只要获取8位数据量,只需使用基本输入和8位数据线,所以将8255A工作在方式0,PA0-PA7接实验台上的8位开关量。2.当使用串口进行数据传送时,虽然同步通信速度远远高于异步通信,可达500kbit/s,但由于其需要有一个时钟来实现发送端和接收端之间的同步,硬件电路复杂,通常计算机之间的通信只采用异步通信。3.由于8251A本身没有时钟,需要外部提供,所以本设计中使用实验台上的8253芯片的计数器2来实现。4:显示和键盘输入均使用DOS功能调用来实现。设计思路框图,如下图所示: 六、硬件设计硬件电路主要分为8位开关量数据获取电路,串行通信数据发送电路,串行通信数据接收电路三个部分。1.8位开关量数据获取电路该电路主要是利用8255并行接口读取8位乒乓开关的数据。此次设计在获取8位开关数据量时采用8255令其工作在方式0,A口输入8位数据,CS#接实验台上CS1口,对应端口为280H-283H,PA0-PA7接8个开关。2.串行通信电路串行通信电路本设计中8253主要为8251充当频率发生器,接线如下图所示。
上传时间: 2013-12-19
上传用户:小火车啦啦啦
The P90CL301 is a highly integrated 16/32 bit micro-controller especially suitable for applications requiring lowvoltage and low power consumption. It is fully software compatible with the 68000. Furthermore, it provides bothstandard as well as advanced peripheral functions on-chip.One of these peripheral functions is the I2C bus. This report describes worked-out driver software (written in C) toprogram the P90CL301 I2C interface. It also contains interface software routines offering the user a quick start inwriting a complete I2C system application.
上传时间: 2014-01-06
上传用户:气温达上千万的