I/O并行口直接驅動LED顯示1. 實驗任務 如圖13所示,利用AT89S51單片機的P0端口的P0.0-P0.7連接到一個共陰數碼管的a-h的筆段上,數碼管的公共端接地。在數碼
上傳時間: 2013-06-15
上傳用戶:kytqcool
LED顯示屏單元板芯片介紹 IC的管腳功能 IC芯片分別:74HC245、74HC595、74HC138、74HC04、4953。各IC管腳功能如下: A: 74HC245功能是放大及緩沖。各引腳如圖 20 和1接電源(+5V) 19腳和10腳接電源地(GND)
上傳時間: 2013-05-17
上傳用戶:小楊高1
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.
標簽: Overvoltage Protection Solutions Driver
上傳時間: 2013-10-14
上傳用戶:jiangfire
Abstract: There are differences between the operation of low-frequency AC transformers and electronic transformersthat supply current to MR16 lamps, and there are also differences in the current draw for MR16 halogen lamps andMR16 LED lamps. These contrasts typically prevent an MR16 LED lamp from operating with most electronictransformers. This article explains how a high-brightness (HB) LED driver optimized for MR16 lamps will allow LEDlamps to be compatible with most electronic transformers.A similar version of this article appeared on Display Plus, July 7, 2012 and in German in Elektronikpraxis, October 1,2012.
上傳時間: 2013-10-14
上傳用戶:playboys0
LED(發光二極管)作為一種新型光源,具有高效節能、綠色環保、使用壽命長等優點,代表著未來照明技術的發展方向。為了體現西藏藏傳佛教文化內涵,本文設計了以凌陽61 A單片機為核心控制器的具有藏語語音朗誦經文和轉經筒自動旋轉的LED臺燈。本文主要介紹了臺燈外觀設計、主電路設計及誦經主程序設計。
上傳時間: 2013-11-10
上傳用戶:tom_man2008
摘要:主要是研究機器人視覺中的LED光源控制器,即基于單片機的恒流源控制器。該恒流源以AT89S51為控制核心,采用了集成運放負反饋型的場效應管恒流源的基本結構。它的整體設計思路是運用負反饋原理,使整個閉環反饋系統處于動態的平衡中,從而達到穩定輸出電流的目的。出于對LED背光源和場效應管的保護,系統中添加了短路保護和過流保護電路。系統采用了12位的A/D 芯片MAX197和l2位的D/A 芯片MAX532,以完成單片機對輸出電流的實時檢測和實時控制。人機接口采用LED數碼管顯示器、獨立鍵盤、外接串口,控制界面直觀、簡潔,具有良好的人機交互性能。
上傳時間: 2013-11-21
上傳用戶:xcsx1945
Abstract: This application note details a step-by-step design process for the MAX16833 high-voltagehigh-brightness LED driver. This process can speed up prototyping and increase the chance for firstpass
上傳時間: 2013-10-09
上傳用戶:tianjinfan
A light-emitting diode (LED) is a semiconductor device that emits narrow-spectrum incoherent light when forward-biased.The color of the emitted light depends on the chemical composition of the semiconductor material used, and can benear-ultraviolet, visible or infrared. LEDs are more prevalent today than ever before, replacing traditional incandescent andfluorescent bulbs in many lighting applications. Incandescents use a heated filament, are subject to breakage and burnoutand operate at a luminous efficiency of 2% to 4%. Fluorescents are more efficient, at 7% to 12%, but require highdrive voltage and contain mercury, a toxic substance that may be eventually banned in certain countries. LEDs, however,produce light directly through electroluminescence, operate at low voltage and can deliver over 20% luminous efficiency.
上傳時間: 2013-11-07
上傳用戶:xiaoyuer
The makers of handheld medical, industrial and consumerdevices use a wide variety of high resolution, small tomedium sized color TFT LCD displays. The power supplydesigners for these displays must contend with shrinkingboard area, tight schedules, and variations in displaytypes and feature requirements. The LTC®3524 simplifi esthe designer’s job by combining a versatile, easily programmed,TFT LCD bias supply and white LED backlightdriver in a low profi le 4mm × 4mm QFN package.
上傳時間: 2013-10-26
上傳用戶:chens000
As environmental concerns over traditional lighting increaseand the price of LEDs decreases, high power LEDsare fast becoming a popular lighting solution for offl ineapplications. In order to meet the requirements of offl inelighting—such as high power factor, high effi ciency, isolationand TRIAC dimmer compatibility—prior LED driversused many external discrete components, resulting incumbersome solutions. The LT®3799 solves complexity,space and performance problems by integrating all therequired functions for offl ine LED lighting.
上傳時間: 2013-10-13
上傳用戶:dongqiangqiang