MAX543雙極性

1、MAX543雙極性MAX543測(cè)試報(bào)告一.MAX543簡(jiǎn)介MAX543是一片12位的電流輸出乘法的數(shù)模轉(zhuǎn)換器。它包括一個(gè)R2R類型的DAC，一個(gè)串行轉(zhuǎn)并行的寄存器，一個(gè)DAC寄存器和控制邏輯。并且轉(zhuǎn)換速率高，功耗低。三線的串行總線易與微處理器接口。二.測(cè)試的電路圖該電路屬于雙級(jí)性輸出硬件電路管腳分配三.功能特點(diǎn)四.引腳介紹五.工作時(shí)序1.2工作流程首先將LOAD端置高，SCLK，SRI清零，等待數(shù)據(jù)的輸入。當(dāng)最高位到SRI時(shí)，把SCLK置高，數(shù)據(jù)被移入串轉(zhuǎn)并寄存器（即脈沖的上升沿）。再將SCLK 清零等待下一位數(shù)據(jù)。重復(fù)12次，令LOAD 為低。開始轉(zhuǎn)換，相應(yīng)的IOUT輸出電流3.源程序用查表

2、的方法，顯示正弦波;12位串行DA，高八位存R1,低四位存R2中spi接口為p3.0,p3.1,p3.2clk equ p3.1sri equ p3.0load equ p3.2org 00hajmp startorg 30hstart:mov r7,#0；查表begin:acall init；初始化寄存器acall init_；初始化DAacall init_da；轉(zhuǎn)換輸出ajmp begininit:mov dptr,#tablemov a,r7movc a,A+dptrmov r1,amov r2,#0ffhmov r3,#8mov r4,#4retinit_:setb load；初始化

3、DAclr sriclr clkretinit_da:acall mobileacall delayacall _adretmobile:；將數(shù)據(jù)移入寄存器clr cloop:mov a,r1rlc amov sri,cmov r1,a;acall delaysetb clkacall delayclr clkacall delaydjnz r3,loopinc r7clr cloopl:mov a,r2rlc amov sri,cmov r2,a;acall delaysetb clkacall delayclr clkacall delaydjnz r4,looplret_ad:clr l

4、oadacall delayretdelay:mov r6,#10h；延時(shí)d1:djnz r6,d1retTABLE:DB 128, 131, 134, 137, 140, 144, 147, 150, 153, 156, 159, 162, 165, 168, 171, 174 DB 177, 180, 182, 185, 188, 191, 194, 196, 199, 201, 204, 206, 209, 211, 214, 216 DB 218, 220, 222, 224, 226, 228, 230, 232, 234, 236, 237, 239, 240, 242, 243,

5、 244 DB 246, 247, 248, 249, 250, 251, 251, 252, 253, 253, 254, 254, 254, 255, 255, 255 DB 255, 255, 255, 254, 254, 254, 253, 253, 252, 252, 251, 250, 249, 248, 247, 246 DB 245, 244, 242, 241, 240, 238, 236, 235, 233, 231, 229, 227, 225, 223, 221, 219 DB 217, 215, 212, 210, 208, 205, 203, 200, 197, 1

6、95, 192, 189, 187, 184, 181, 178 DB 175, 172, 169, 167, 164, 160, 157, 154, 151, 148, 145, 142, 139, 136, 133, 130 DB 126, 123, 120, 117, 114, 111, 108, 105, 102, 99 , 96 , 92 , 89 , 87 , 84 , 81DB 78 , 75 , 72 , 69 , 67 , 64 , 61 , 59 , 56 , 53 , 51 , 48 , 46 , 44 , 41 , 39DB 37 , 35 , 33 , 31 , 29

7、 , 27 , 25 , 23 , 21 , 20 , 18 , 16 , 15 , 14 , 12 , 11DB 10 , 9 , 8 , 7 , 6 , 5 , 4 , 4 , 3 , 3 , 2 , 2 , 1 , 1 , 1 , 0 DB 0 , 1 , 1 , 1 , 2 , 2 , 3 , 3 , 4 , 5 , 5 , 6 , 7 , 8 , 9 , 10 DB 12 , 13 , 14 , 16 , 17 , 19 , 20 , 22 , 24 , 26 , 28 , 30 , 32 , 34 , 36 , 38DB 40 , 42 , 45 , 47 , 50 , 52 , 55 , 57 , 60 , 62 , 6