LPCXpresso845MAX use ADC_Seqa_Seqb example code have pulse on ADC2 pin

[ristchen]

Why LPCXpresso845MAX use ADC_Seqa_Seqb example code have pulse on ADC2(PIO14) pin when get ADC value?

[xiangjun_rong]

Hi, Chen,

I have checked the voltage spike on the PIO14/ADC2, I suppose this is a noise, the noise generally happens for the float input pins or high impedance input pin.

I suggest that you can connect a RC circuit for the ADC analog input channel. for example, this is a RC circuit, using 100 ohm and 2.2nF capacitor.

Does the noise take effect on the ADC sample?

BR

XiangJun Rong