430f5418内部ad12采样不稳定,怎么办
求解。用430内部ad12采样信号,如果在输入短路感觉挺好的,为什么有信号输入就不稳定呢?我只能通过使用很多的采集做平均来弥补,速度太慢了。请求高手解答。
P6SEL |= 0xFF; // Enable A/D channel A0
P6DIR &= 0x00;
REFCTL0 |= REFMSTR + REFVSEL_2 + REFON;
/* Initialize ADC12_A */
ADC12CTL0 = ADC12ON+ADC12MSC+ADC12SHT0_2; // Turn on ADC12, set sampling time
ADC12CTL1 = ADC12SHP+ADC12CONSEQ_1; // Use sampling timer, single sequence
ADC12MCTL0 = ADC12SREF_1+ADC12INCH_0; // ref+=AVcc, channel = A0
ADC12MCTL1 = ADC12SREF_1+ADC12INCH_1; // ref+=AVcc, channel = A1
ADC12MCTL2 = ADC12SREF_1+ADC12INCH_2; // ref+=AVcc, channel = A1
ADC12MCTL3 = ADC12SREF_1+ADC12INCH_3; // ref+=AVcc, channel = A1
ADC12MCTL4 = ADC12SREF_1+ADC12INCH_4; // ref+=AVcc, channel = A1
ADC12MCTL5 = ADC12SREF_1+ADC12INCH_5; // ref+=AVcc, channel = A1
ADC12MCTL6 = ADC12SREF_1+ADC12INCH_6; // ref+=AVcc, channel = A1
ADC12MCTL7 = ADC12SREF_1+ADC12INCH_7+ADC12EOS; // ref+=AVcc, channel = A1
ADC12CTL0 |= ADC12ENC; // Enable conversions
delay_us(100); 电压参考是否稳定?电源的文波大小等等? 除了楼上说的以外,430单片机AD输入阻抗挺低的(好像是2k左右),如果所采集的信号输出阻抗不够低就会不准确 alengend 发表于 2013-6-11 18:55 static/image/common/back.gif
除了楼上说的以外,430单片机AD输入阻抗挺低的(好像是2k左右),如果所采集的信号输出阻抗不够低就会不准 ...
我运放放大信号后加了个1k的电阻过来,不知道如何?但是我这个电阻都有调整,不过没有明显效果。
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