LED显示屏的诞生，直接改变了整个世界，大屏幕的出现让我们感受到了绚丽的色彩，超大的屏幕，高清的画质。LED显示屏目前占据了户外80%的市场。LED显示屏的性能与LED驱动芯片息息相关。郑州LED显示屏的小编(bian)来为大家(jia)讲(jiang)解一下！

1、驱动芯片种类:

 LED驱(qu)动(dong)芯(xin)(xin)(xin)片(pian)(pian)(pian)(pian)(pian)可分为通用(yong)芯(xin)(xin)(xin)片(pian)(pian)(pian)(pian)(pian)和(he)专用(yong)芯(xin)(xin)(xin)片(pian)(pian)(pian)(pian)(pian)两种。所谓的(de)(de)(de)(de)(de)(de)通用(yong)芯(xin)(xin)(xin)片(pian)(pian)(pian)(pian)(pian)，其(qi)芯(xin)(xin)(xin)片(pian)(pian)(pian)(pian)(pian)本身并非(fei)专门为LED而(er)设计，而(er)是(shi)(shi)一些(xie)具有LED显(xian)(xian)示(shi)屏(ping)部分逻辑功能的(de)(de)(de)(de)(de)(de)逻辑芯(xin)(xin)(xin)片(pian)(pian)(pian)(pian)(pian)(如(ru)串-并移位寄存器)。而(er)专用(yong)芯(xin)(xin)(xin)片(pian)(pian)(pian)(pian)(pian)是(shi)(shi)指按照LED发光特性而(er)设计专门用(yong)于LED显(xian)(xian)示(shi)屏(ping)的(de)(de)(de)(de)(de)(de)驱(qu)动(dong)芯(xin)(xin)(xin)片(pian)(pian)(pian)(pian)(pian)。LED是(shi)(shi)电流特性器件(jian)，即在饱和(he)导通的(de)(de)(de)(de)(de)(de)前提下，其(qi)亮度随着电流的(de)(de)(de)(de)(de)(de)变(bian)化而(er)变(bian)化，而(er)不是(shi)(shi)靠(kao)调(diao)节其(qi)两端的(de)(de)(de)(de)(de)(de)电压而(er)变(bian)化。因此专用(yong)芯(xin)(xin)(xin)片(pian)(pian)(pian)(pian)(pian)一个最大的(de)(de)(de)(de)(de)(de)特点就是(shi)(shi)提供恒(heng)流源(yuan)。恒(heng)流源(yuan)可以保证(zheng)LED的(de)(de)(de)(de)(de)(de)稳定驱(qu)动(dong)，消除LED的(de)(de)(de)(de)(de)(de)闪烁(shuo)现(xian)象，是(shi)(shi)LED显(xian)(xian)示(shi)屏(ping)显(xian)(xian)示(shi)高(gao)品质画面的(de)(de)(de)(de)(de)(de)前提。有些(xie)专用(yong)芯(xin)(xin)(xin)片(pian)(pian)(pian)(pian)(pian)还针对不同行业(ye)的(de)(de)(de)(de)(de)(de)要求增加了一些(xie)特殊的(de)(de)(de)(de)(de)(de)功能，如(ru)亮度调(diao)节、错误检测等。郑州LED显(xian)(xian)示(shi)屏(ping)的(de)(de)(de)(de)(de)(de)小编(bian)将重(zhong)点介绍(shao)专用(yong)驱(qu)动(dong)芯(xin)(xin)(xin)片(pian)(pian)(pian)(pian)(pian)。

2、通用芯片

通(tong)用(yong)(yong)芯片一般(ban)用(yong)(yong)于(yu)LED显(xian)(xian)示(shi)屏(ping)的(de)(de)(de)低(di)档产品(pin)(pin)，如户内的(de)(de)(de)单色屏(ping)，双色屏(ping)等(deng)。最(zui)常用(yong)(yong)的(de)(de)(de)通(tong)用(yong)(yong)芯片是74HC595。74HC595具有8位锁存、串—并移位寄存器和三态输出。每路(lu)最(zui)大可(ke)输出35mA的(de)(de)(de)电流(非恒流)。一般(ban)的(de)(de)(de)IC厂家(jia)都可(ke)生(sheng)产此类芯片。显(xian)(xian)示(shi)屏(ping)行业(ye)中常用(yong)(yong)Motorola(Onsemi)，Philips及ST等(deng)厂家(jia)的(de)(de)(de)产品(pin)(pin)，其中Motorola的(de)(de)(de)产品(pin)(pin)性(xing)能较(jiao)好(hao)。

3、专用芯片

专用(yong)芯片具有输出电流大、恒流等(deng)特点，比较适用(yong)于电流大，画质要(yao)求高的场合，如户外全彩屏、室内(nei)全彩屏等(deng)。

专用芯片(pian)的关(guan)键性能参数(shu)(shu)有最(zui)大输(shu)出(chu)(chu)(chu)电流、恒流源(yuan)输(shu)出(chu)(chu)(chu)路数(shu)(shu)、电流输(shu)出(chu)(chu)(chu)误差(cha)(bit-bit,chip-chip)和数(shu)(shu)据移位时钟等。

4、最大输出电流

目前主流恒(heng)流源芯片(pian)的(de)(de)最(zui)大(da)输出(chu)电(dian)(dian)流多定(ding)(ding)义(yi)为单(dan)路最(zui)大(da)输出(chu)电(dian)(dian)流，一般在90mA左右。恒(heng)流是专用(yong)芯片(pian)的(de)(de)最(zui)根本特(te)性，也是得到高画质(zhi)的(de)(de)基础。而每(mei)个(ge)通道同时(shi)输出(chu)恒(heng)定(ding)(ding)电(dian)(dian)流的(de)(de)最(zui)大(da)值(即最(zui)大(da)恒(heng)定(ding)(ding)输出(chu)电(dian)(dian)流)对显示屏更有意义(yi)，因为在白(bai)平(ping)衡状态下，要求(qiu)每(mei)一路都同时(shi)输出(chu)恒(heng)流电(dian)(dian)流。一般最(zui)大(da)恒(heng)流输出(chu)电(dian)(dian)流小于允许最(zui)大(da)输出(chu)电(dian)(dian)流。

5、恒流源输出路数

恒流(liu)源(yuan)(yuan)输出路数主(zhu)要有8(8位源(yuan)(yuan))和16(16位源(yuan)(yuan))两种(zhong)规格，现在16位源(yuan)(yuan)基本上占主(zhu)流(liu)：如TLC5921，TB62706/TB62726，MBl5026/MBl5016等。16位源(yuan)(yuan)芯片(pian)主(zhu)要优势在于(yu)(yu)减少(shao)了芯片(pian)尺寸，便于(yu)(yu)LED驱动板(PCB)布线，特别是对于(yu)(yu)点间距较(jiao)小(xiao)的(de)PCB更是有利。

6、电流输出误差

电(dian)(dian)(dian)(dian)流(liu)输出(chu)误(wu)(wu)(wu)差(cha)(cha)分(fen)为两种，一(yi)种是(shi)位间(jian)(jian)电(dian)(dian)(dian)(dian)流(liu)误(wu)(wu)(wu)差(cha)(cha)，即同(tong)一(yi)个(ge)芯(xin)片(pian)(pian)每路(lu)输出(chu)之间(jian)(jian)的(de)(de)误(wu)(wu)(wu)差(cha)(cha);另(ling)一(yi)种是(shi)片(pian)(pian)间(jian)(jian)电(dian)(dian)(dian)(dian)流(liu)误(wu)(wu)(wu)差(cha)(cha)，即不同(tong)芯(xin)片(pian)(pian)之间(jian)(jian)输出(chu)电(dian)(dian)(dian)(dian)流(liu)的(de)(de)误(wu)(wu)(wu)差(cha)(cha)。电(dian)(dian)(dian)(dian)流(liu)输出(chu)误(wu)(wu)(wu)差(cha)(cha)是(shi)个(ge)很(hen)关键的(de)(de)参数，对显示屏(ping)(ping)的(de)(de)均匀性(xing)影响很(hen)大。郑州LED显示屏(ping)(ping)的(de)(de)小编(bian)提醒大家误(wu)(wu)(wu)差(cha)(cha)越(yue)大，LED显示屏(ping)(ping)的(de)(de)均匀性(xing)越(yue)差(cha)(cha)，很(hen)难使屏(ping)(ping)体(ti)达到白平衡。目前主(zhu)流(liu)恒(heng)流(liu)源芯(xin)片(pian)(pian)的(de)(de)位间(jian)(jian)电(dian)(dian)(dian)(dian)流(liu)误(wu)(wu)(wu)差(cha)(cha)一(yi)般小于(yu)土6%，片(pian)(pian)间(jian)(jian)电(dian)(dian)(dian)(dian)流(liu)误(wu)(wu)(wu)差(cha)(cha)小于(yu)-+15%o

7、数据移位时钟

LED显(xian)(xian)(xian)示(shi)(shi)(shi)屏(ping)驱动芯片(pian)的(de)(de)(de)基本功(gong)能中都包含串行移(yi)(yi)位寄(ji)存器(qi)的(de)(de)(de)功(gong)能，以便(bian)于实现显(xian)(xian)(xian)示(shi)(shi)(shi)数(shu)据(ju)(ju)(ju)的(de)(de)(de)级联与传(chuan)输(shu)，构建大(da)尺寸多显(xian)(xian)(xian)示(shi)(shi)(shi)点的(de)(de)(de)LED显(xian)(xian)(xian)示(shi)(shi)(shi)屏(ping)。数(shu)据(ju)(ju)(ju)移(yi)(yi)位时钟决定了显(xian)(xian)(xian)示(shi)(shi)(shi)数(shu)据(ju)(ju)(ju)的(de)(de)(de)传(chuan)输(shu)速(su)度，对显(xian)(xian)(xian)示(shi)(shi)(shi)屏(ping)显(xian)(xian)(xian)示(shi)(shi)(shi)数(shu)据(ju)(ju)(ju)的(de)(de)(de)更(geng)新速(su)率(lv)起到(dao)至关重要的(de)(de)(de)作用。郑州LED显(xian)(xian)(xian)示(shi)(shi)(shi)屏(ping)的(de)(de)(de)小编(bian)提醒大(da)家(jia)作为大(da)尺寸显(xian)(xian)(xian)示(shi)(shi)(shi)器(qi)件，显(xian)(xian)(xian)示(shi)(shi)(shi)刷(shua)新率(lv)应该在(zai)85Hz以上(shang)，才能保(bao)证稳(wen)定的(de)(de)(de)画(hua)面(mian)(无扫(sao)描(miao)闪烁感)。较高(gao)的(de)(de)(de)数(shu)据(ju)(ju)(ju)移(yi)(yi)位时钟是显(xian)(xian)(xian)示(shi)(shi)(shi)屏(ping)获取高(gao)刷(shua)新率(lv)画(hua)面(mian)的(de)(de)(de)基础。目前(qian)主流恒流源(yuan)芯片(pian)移(yi)(yi)位时钟频率(lv)一(yi)般都在(zai)15MHz以上(shang)。