Linear Technology offers a variety of devices that simplifyconverting power from a USB cable, but the LTC®3455represents the highest level of functional integration yet. The LTC3455 seamlessly manages power flowbetween an AC adapter, USB cable and Li-ion battery,while complying with USB power standards, all from a4mm × 4mm QFN package. In addtion, two high efficiencysynchronous buck converters generate low voltage railswhich most USB-powered peripherals require. TheLTC3455 also provides power-on reset signals for themicroprocessor, a Hot SwapTM output for poweringmemory cards as well as an uncommitted gain blocksuitable for use as a low-battery comparator or an LDOcontroller. The PCB real estate required for the entire USBpower control circuit and two DC/DC converters is only225mm2.
上傳時間： 2013-11-02
上傳用戶：名爵少年
The LTC®4099 high effi ciency USB power manager andLi-Ion/Polymer battery charger seamlessly managespower distribution from multiple sources in portableapplications. It is differentiated from other USB powermanagers by its bidirectional I2C port that allows the hostmicroprocessor to control and monitor all aspects of theUSB power management and battery charging processes.In addition, a programmable interrupt generation functionalerts the host microprocessor to changes in device statusand provides unprecedented control of power managementfunctions. This high degree of confi gurability allowspost-layout changes in operation, even changes in thefi eld, and it allows a single qualifi ed device to be usedin a variety of products, thus reducing design time andeasing inventory management.
上傳時間： 2013-10-22
上傳用戶：18602424091
敘述了基于過采樣技術,使用軟件方法提高單片機片內A/ D 分辨率的基本原理及實現方法。給出了一個實現示例,將C8051F040 片內12 位分辨率ADC 提高到16 位分辨率。
上傳時間： 2014-01-08
上傳用戶：a3318966
為解決當前計算機串行通訊接口只有USB，難以滿足舊型號設備或某些單片機要求RS232通訊的問題，設計出兩款RS232/USB電路。采用CH341A與MAX223集成電路芯片構建標準9線RS232/USB通用接口轉換器，無需編程。采用CH341A與PIC16F877A構建單片機與計算機之間的USB通訊電路，軟件遵循RS232通訊協議，硬件進行電平轉換。實際使用表明，這兩款產品與計算機端Windows 操作系統下的串口應用程序完全兼容，且通訊過程中無握手失敗現象。 Abstract: To solve the problem that current computer serial communication only with USB interface can not satisfy with the old type equipments or MCU to communicate with RS232， two kinds of RS232/USB circuit were designed.CH341A and MAX223 integrated circuit chips were used to create a standard 9-line RS232/USB universal interface convertor without programme. CH341A and PIC16F877A chips were adopted to build the USB communication circuit between computers and MCU. The software follows RS232 communication protocol， and the hardware converts electrical levels. Actual practices indicate that the two manufactures are compatible with serial application program of Windows operation system completely，and get avoid of handshake lost.
上傳時間： 2013-11-03
上傳用戶：siying
單片機作為一種微型計算機，其內部具有一定的存儲單元（8031除外），但由于其內部存儲單元及端口有限，很多情況下難以滿足實際需求。為此介紹一種新的擴展方法，將數據線與地址線合并使用，通過軟件控制的方法實現數據線與地址線功能的分時轉換，數據線不僅用于傳送數據信號，還可作為地址線、控制線，用于傳送地址信號和控制信號，從而實現單片機與存儲器件的有效連接。以單片機片外256KB數據存儲空間的擴展為例，通過該擴展方法，僅用10個I/O端口便可實現，與傳統的擴展方法相比，可節約8個I/O端口。 Abstract: As a micro-computer,the SCM internal memory has a certain units(except8031),but because of its internal storage units and the ports are limited,in many cases it can not meet the actual demand.So we introduced a new extension method,the data line and address lines combined through software-controlled approach to realize the time-conversion functions of data lines and address lines,so the data lines not only transmited data signals,but also served as address lines and control lines to transmit address signals and control signals,in order to achieve an effective connection of microcontroller and memory chips.Take microcontroller chip with256KB of data storage space expansion as example,through this extension method,with only10I/O ports it was achieved,compared with the traditional extension methods,this method saves8I/O ports.
上傳時間： 2014-12-26
上傳用戶：adada
針對眾多低成本數據采集需求，采用帶有片上USB控制器和D/A轉換器的混合信號微處理器C8051F340，設計了一款可通過USB接口和LabVIEW圖形用戶界面實現與PC機聯機的數據采集器，同時借助系統的SD卡存儲獨立實現現場長時間采集數據。該數據采集器成本低，結構簡單，體積小，已成功用于工業現場。 Abstract: Aiming at the need of low cost data acquisition, a data acquisition device is designed based on C8051F340 which is a mixed-signal microcontroller and integrates USB controller and A/D controller on a chip.The data acquisition device which can combine with PC by USB interface and LabVIEW graphical user interface,can realize data acquisition. At the same time,it can be solely run a long time in virtue of SD card in field.The date aequisition device features low cost,simple structure and little sharp, and it has been used in industry field.
上傳時間： 2014-05-31
上傳用戶：1109003457
以AVR單片機ATmega8和USB接口器件PDIUSBD12為核心，基于標準的USB1.1協議，設計一種通用USB接口模塊，以滿足嵌入式系統中對USB接口的需求。對模塊的硬件電路或單片機固件程序的硬件接口層稍加修改即可用于其他各種微處理器。該模塊可為各種嵌入式系統增加USB接口,實現與USB主機系統通信。 Abstract: Based on AVR microcontroller ATmega8 and USB interface chip PDIUSBD12, a general USB interface module is designed according to USB1.1 protocol for various requirements of embedded systems. Only with few modifications in circuit or hardware abstract layer of firmware, the module can be used on many types of microprocessors. All kinds of embedded systems can realize high speed and stable communication with USB host systems, owing to the facility of this module.
上傳時間： 2014-01-08
上傳用戶：趙云興
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
上傳時間： 2013-10-28
上傳用戶：13691535575
AVR mega128學習板 聯系 楊迪 15336417867 0531-55508458 QQ：1347978253 http://www.easyele.cn AVR mega128學習板是AVRVI設計生產的AVR學習開發生產工具，以Atmega128為核心，采用底板，核心板的組織形式，子板和母板組合，也可以分開。集成AVR JTAG ICE仿真器和STK500 ISP編程器，用戶只需要再擁有一臺計算機即可進行系統的學習。為了更好的支持客戶的學習和開發，AVR mega128學習板板通訊接口升級為USB接口，方便計算機沒有串口的朋友。貨號：EasyAVRM128SK-A 規格： 套 重量：300克 單價498/套。 AVR mega128學習板他還是一個強大的開發工具。通過它進行學習后，你會覺得畢業設計如此簡單，輕松應對電子設計大賽，機器人大賽，對電子產品的設計有進一步的認知，建立起學習ARM，DSP，FPGA的良好基礎。AVR mega128學習板這個性價比高的專業工具是你的不二選擇。購買本產品贈送LCD1602液晶一塊。AVR mega128學習板是仿真器，編程器，開發板，核心板四合一的集功能于一體的產品，并且可以分開獨立使用。 AVR mega128學習板于2008年開發，基于AVR中較高檔芯片ATmega128設計，采用子板和母版疊加的方式，集成仿真和下載功能，原串口版本得到廣大用戶的支持和認可，2009年底升級為USB版本，使用更方便，兼容開發型號：ATmega64，特別適合新手學習，工程師快速產品開發。 AVR mega128學習板的關鍵特點： 1.采用核心板和主板分離的形式，在系統的學習之后，可以把核心板直接用于產品中，快速搭建系統。 2.AVR mega128學習板上集成了AVR JTAG ICE仿真器和AVR ISP編程器。 您只需要再擁有一臺計算機，而不需要購買仿真器和編程器就可以學習開發了。 3.信號調理電路，輸入0～10V，軌至軌信號調理。 學習階段：AVR mega128學習板讓你熟悉AVR的各種資源的應用，板載的常用外設，可以讓你方便的進行各種學習實驗。板載編程器和仿真器，讓你無需擔心自己的接線是否正確，即插即用。開發階段：AVR mega128學習板的核心板可以用于產品核心，板子雖小，五臟俱全，最小系統板的基本電路，讓你得心應手，標準的插針，可以將核心板直接插在萬用板上使用，擴展方便。仿真器功能，讓你開發變得更加簡單，輕松找到程序中的各種問題，予以解決，加快開發。AVR mega128學習板的ISP 功能可以讓你禁用JTAG接口，節省IO，并且讓AD轉換更加準確。生產階段：編程器提供官方推薦的ISP在線下載方式，速度快，編程完成后不占用CPU的任何資源。 AVR mega128學習板是進入嵌入式開發領域的專業入門學習和開發工具，是學生，初學者，工程師的必備良弓。我們還為客戶提供可選配件18B20溫度傳感器 10元 1602液晶 20元 12864液晶 80元 7.5/12V電源 12元 mini128核心板 147元 mini64核心板 138元。歡迎有志之士咨詢選購。 想找一份好工作嗎？ 你想成為一名電子設計工程師嗎？ 你對電子設計有濃厚興趣，而沒有工具嗎？ 看了很久的程序方面的書籍，卻沒有實踐的機會嗎？ 需要開發產品，想快速入門？ 想參加電子設計大賽，機器人大賽嗎？ 這個性價比高的專業工具是你的不二選擇。
上傳時間： 2013-11-13
上傳用戶：ljj722
Stellaris(群星)單片機的片上FLASH編程(英) INFORMATION IN THIS DOCUMENT IS PROVIDED IN CONNECTION WITH LUMINARY MICRO PRODUCTS. NO LICENSE,EXPRESS OR IMPLIED, BY ESTOPPEL OR OTHERWISE, TO ANY INTELLECTUAL PROPERTY RIGHTS IS GRANTED BY THISDOCUMENT. EXCEPT AS PROVIDED IN LUMINARY MICRO’S TERMS AND CONDITIONS OF SALE FOR SUCH PRODUCTS,LUMINARY MICRO ASSUMES NO LIABILITY WHATSOEVER, AND LUMINARY MICRO DISCLAIMS ANY EXPRESS OR IMPLIEDWARRANTY, RELATING TO SALE AND/OR USE OF LUMINARY MICRO’S PRODUCTS INCLUDING LIABILITY OR WARRANTIESRELATING TO FITNESS FOR A PARTICULAR PURPOSE, MERCHANTABILITY, OR INFRINGEMENT OF ANY PATENT, COPYRIGHTOR OTHER INTELLECTUAL PROPERTY RIGHT. LUMINARY MICRO’S PRODUCTS ARE NOT INTENDED FOR USE IN MEDICAL,LIFE SAVING, OR LIFE-SUSTAINING APPLICATIONS.
上傳時間： 2013-10-22
上傳用戶：JamesB
