一、概述

MAX7219/MAX7221是一種集成化的串行輸入/輸出共陰極顯示驅(qū)動(dòng)器,它連接微處理器與8位數(shù)字的7段數(shù)字LED顯示，也可以連接條線圖顯示器或者64個(gè)獨(dú)立的LED。其上包括一個(gè)片上的B型BCD編碼器、多路掃描回路，段字驅(qū)動(dòng)器，而且還有一個(gè)8*8的靜態(tài)RAM用來存儲(chǔ)每一個(gè)數(shù)據(jù)。

只有一個(gè)外部寄存器用來設(shè)置各個(gè)LED的段電流。MAX7221與SPI?、QSPI?以及 MICROWIRE?相兼容，同時(shí)它有限制回轉(zhuǎn)電流的段驅(qū)動(dòng)來減少EMI（電磁干擾）。一個(gè)方便的四線串行接口可以聯(lián)接所有通用的微處理器。

每個(gè)數(shù)據(jù)可以尋址在更新時(shí)不需要改寫所有的顯示。MAX7219/MAX7221同樣允許用戶對(duì)每一個(gè)數(shù)據(jù)選擇編碼或者不編碼。整個(gè)設(shè)備包含一個(gè)150μA的低功耗關(guān)閉模式，模擬和數(shù)字亮度控制，一個(gè)掃描限制寄存器允許用戶顯示1-8位數(shù)據(jù)，還有一個(gè)讓所有LED發(fā)光的檢測(cè)模式。在應(yīng)用時(shí)要求3V的操作電壓或segment blinking，可以查閱MAX6951數(shù)據(jù)資料。

二、應(yīng)用

條線圖顯示 儀表面板 工業(yè)控制 LED矩陣顯示

三、管腳配置

四、功能特點(diǎn)

1. 10MHz 連續(xù)串行口
2. 獨(dú)立的LED 段控制
3. 數(shù)字的譯碼與非譯碼選擇
4. 150μA 的低功耗關(guān)閉模式
5. 亮度的數(shù)字和模擬控制
6. 高電壓中斷顯示
7. 共陰極LED 顯示驅(qū)動(dòng)
8. 限制回轉(zhuǎn)電流的段驅(qū)動(dòng)來減少EMI（MAX7221）
9. SPI, QSPI, MICROWIRE串行接口（MAX7221）
10. 24 腳的DIP 和SO 封裝

五、分類信息

芯片 工作溫度范圍 管腳封裝

MAX7219CNG 0°C to +70°C 24 Narrow Plastic DIP

MAX7219CWG 0°C to +70°C 24 Wide SO

MAX7219C/D 0°C to +70°C Dice*

MAX7219ENG -40°C to +85°C 24 Narrow Plastic DIP

MAX7219EWG -40°C to +85°C 24 Wide SO

MAX7219ERG -40°C to +85°C 24 Narrow CERDIP

五、典型應(yīng)用電路

六、功能圖表

七、時(shí)序圖

MAX7219原理圖

MAX7219驅(qū)動(dòng)程序

#include 
#include 


#define uchar unsigned char
#define uint  unsigned int


//定義Max7219端口
sbit Max7219_pinCLK = P2^2;
sbit Max7219_pinCS  = P2^1;
sbit Max7219_pinDIN = P2^0;
uchar code disp1[38][8]={
{0x3C,0x42,0x42,0x42,0x42,0x42,0x42,0x3C},//0
{0x10,0x18,0x14,0x10,0x10,0x10,0x10,0x10},//1
{0x7E,0x2,0x2,0x7E,0x40,0x40,0x40,0x7E},//2
{0x3E,0x2,0x2,0x3E,0x2,0x2,0x3E,0x0},//3
{0x8,0x18,0x28,0x48,0xFE,0x8,0x8,0x8},//4
{0x3C,0x20,0x20,0x3C,0x4,0x4,0x3C,0x0},//5
{0x3C,0x20,0x20,0x3C,0x24,0x24,0x3C,0x0},//6
{0x3E,0x22,0x4,0x8,0x8,0x8,0x8,0x8},//7
{0x0,0x3E,0x22,0x22,0x3E,0x22,0x22,0x3E},//8
{0x3E,0x22,0x22,0x3E,0x2,0x2,0x2,0x3E},//9
{0x8,0x14,0x22,0x3E,0x22,0x22,0x22,0x22},//A
{0x3C,0x22,0x22,0x3E,0x22,0x22,0x3C,0x0},//B
{0x3C,0x40,0x40,0x40,0x40,0x40,0x3C,0x0},//C
{0x7C,0x42,0x42,0x42,0x42,0x42,0x7C,0x0},//D
{0x7C,0x40,0x40,0x7C,0x40,0x40,0x40,0x7C},//E
{0x7C,0x40,0x40,0x7C,0x40,0x40,0x40,0x40},//F
{0x3C,0x40,0x40,0x40,0x40,0x44,0x44,0x3C},//G
{0x44,0x44,0x44,0x7C,0x44,0x44,0x44,0x44},//H
{0x7C,0x10,0x10,0x10,0x10,0x10,0x10,0x7C},//I
{0x3C,0x8,0x8,0x8,0x8,0x8,0x48,0x30},//J
{0x0,0x24,0x28,0x30,0x20,0x30,0x28,0x24},//K
{0x40,0x40,0x40,0x40,0x40,0x40,0x40,0x7C},//L
{0x81,0xC3,0xA5,0x99,0x81,0x81,0x81,0x81},//M
{0x0,0x42,0x62,0x52,0x4A,0x46,0x42,0x0},//N
{0x3C,0x42,0x42,0x42,0x42,0x42,0x42,0x3C},//O
{0x3C,0x22,0x22,0x22,0x3C,0x20,0x20,0x20},//P
{0x1C,0x22,0x22,0x22,0x22,0x26,0x22,0x1D},//Q
{0x3C,0x22,0x22,0x22,0x3C,0x24,0x22,0x21},//R
{0x0,0x1E,0x20,0x20,0x3E,0x2,0x2,0x3C},//S
{0x0,0x3E,0x8,0x8,0x8,0x8,0x8,0x8},//T
{0x42,0x42,0x42,0x42,0x42,0x42,0x22,0x1C},//U
{0x42,0x42,0x42,0x42,0x42,0x42,0x24,0x18},//V
{0x0,0x49,0x49,0x49,0x49,0x2A,0x1C,0x0},//W
{0x0,0x41,0x22,0x14,0x8,0x14,0x22,0x41},//X
{0x41,0x22,0x14,0x8,0x8,0x8,0x8,0x8},//Y
{0x0,0x7F,0x2,0x4,0x8,0x10,0x20,0x7F},//Z
{0x8,0x7F,0x49,0x49,0x7F,0x8,0x8,0x8},//中
{0xFE,0xBA,0x92,0xBA,0x92,0x9A,0xBA,0xFE},//國(guó)
};
void Delay_xms(uint x)
{
 uint i,j;
 for(i=0;i