Abstract: This application note presents an overview of the operational characteristics of accurate I²C real-time clocks (RTCs),including the DS3231, DS3231M, and DS3232. It focuses on general application guidelines that facilitate use of device resources forpower management, I²C communication circuit configurations, and I²C characteristics relative to device power-up sequences andinitializations. Additional discussions on decoupling are provided to support developing strategies for mitigating power-supply pushingof device frequency.
上傳時間: 2013-11-23
上傳用戶:WMC_geophy
Precision 16-bit analog outputs with softwareconfigurableoutput ranges are often needed in industrialprocess control equipment, analytical and scientificinstruments and automatic test equipment. In the past,designing a universal output module was a daunting taskand the cost and PCB real estate associated with thisfunction were problematic, if not prohibitive.
上傳時間: 2014-12-23
上傳用戶:如果你也聽說
基于MDK RTX 的COrtex—M3 多任務應用設計 武漢理工大學 方安平 武永誼 摘要:本文描述了如何在Cortex—M3 上使用MDK RL—RTX 的方法,并給出了一個簡單的多任務應用設計。 關鍵詞:MDK RTX,Cortex,嵌入式,ARM, STM32F103VB 1 MDK RL—RTX 和COrtex—M3 概述 MDK 開發套件源自德國Keil 公司,是ARM 公司目前最新推出的針對各種嵌入式處理器 的軟件開發工具。MDKRL—IUX 是一個實時操作系統(RTOS)內核,完全集成在MDK 編譯器中。廣泛應用于ARM7、ARM9 和Cortex-M3 設備中。它可以靈活解決多任務調度、維護和時序安排等問題。基于RL—I 訂X 的程序由標準的C 語言編寫,由Real—View 編譯器進行編譯。操作系統依附于C 語言使聲明函數更容易,不需要復雜的堆棧和變量結構配置,大大簡化了復雜的軟件設計,縮短了項目開發周期。
上傳時間: 2014-12-23
上傳用戶:Yue Zhong
Abstract: Large steel buildings, automobiles, mountains, even people survive real atmospheric lightning.
上傳時間: 2013-11-11
上傳用戶:zgu489
The Circuit Designer’s Companion Second edition Tim Williams
標簽: Designers Companion Circuit PCB
上傳時間: 2013-11-04
上傳用戶:fredguo
此提出了一種基于Matlab/Simulink及實時代碼生成工具R哪(Real.Time Workshop)的電力電子與電力傳動控制系統軟件的設計方法。首先在Simulink下搭建控制系統模型,進行相應仿真完善,驗證控制算法,根據目標DSP型號添加相應DSP內核、外設并設置控制參數,然后直接將模型轉化為相應DSP的C源代碼.在相應的硬件平臺支持下即可完成相關實驗。
上傳時間: 2013-11-04
上傳用戶:wincoder
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
Multiple-voltage electronics systems often requirecomplex supply voltage tracking or sequencing, whichif not met, can result in system faults or even permanentfailures in the fi eld. The design diffi culties in meetingthese requirements are often compounded in distributedpowerarchitectures where point-of-load (POL) DC/DCconverters or linear regulators are scattered across PCboard space, sometimes on different board planes. Theproblem is that power supply circuitry is often the lastcircuitry to be designed into the board, and it must beshoehorned into whatever little board real estate is left.Often, a simple, drop-in, fl exible solution is needed tomeet these requirements.
上傳時間: 2013-10-08
上傳用戶:15071087253
One of the fi rst lessons in a basic electronics coursecovers the symbols for resistors, capacitors, inductors,voltage sources and current sources. Althougheach symbol represents a functional component of areal-world circuit, only some of the symbols have directphysical counterparts. For instance, the three discretepassive devices—resistors, capacitors, inductors—canbe picked off a shelf and placed on a real board muchas their symbolic analogs appear in a basic schematic.Likewise, while voltage sources have no direct 2-terminalanalog, a voltage source can be easily built with an offthe-shelf linear regulator.
上傳時間: 2013-11-24
上傳用戶:simonpeng
HIGH SPEED 8051 μC CORE - Pipe-lined Instruction Architecture; Executes 70% of Instructions in 1 or 2 System Clocks - Up to 25MIPS Throughput with 25MHz System Clock - 22 Vectored Interrupt Sources MEMORY - 4352 Bytes Internal Data RAM (256 + 4k) - 64k Bytes In-System Programmable FLASH Program Memory - External Parallel Data Memory Interface – up to 5Mbytes/sec DIGITAL PERIPHERALS - 64 Port I/O; All are 5V tolerant - Hardware SMBusTM (I2CTM Compatible), SPITM, and Two UART Serial Ports Available Concurrently - Programmable 16-bit Counter/Timer Array with 5 Capture/Compare Modules - 5 General Purpose 16-bit Counter/Timers - Dedicated Watch-Dog Timer; Bi-directional Reset CLOCK SOURCES - Internal Programmable Oscillator: 2-to-16MHz - External Oscillator: Crystal, RC, C, or Clock - real-time Clock Mode using Timer 3 or PCA SUPPLY VOLTAGE ........................ 2.7V to 3.6V - Typical Operating Current: 10mA @ 25MHz - Multiple Power Saving Sleep and Shutdown Modes 100-Pin TQFP (64-Pin Version Available) Temperature Range: –40°C to +85°C
標簽: C8051F020
上傳時間: 2013-10-12
上傳用戶:lalalal