Multiple Analog input problem in STM32L432KC

[JLiao]

Dear All,

I develop my project on the:

1. Nculeo-L432
2. mbed-os-5.13 and v5.12

I try do to use the polling and DMA to read the multiple analog input, from PA_0 and PA_1.

The DMA and Polling got the same result as below:

1. The PA_0 value is valid 0v - 3.3v (0 - FFFh) when PA_1 connect to GND.
2. The PA_0 value is invalid 0v - 3.3v ( 478h-BB8h) when PA_1 disconnect (floating).

Why PA_1 impact the PA_0 ?

If I try to read the PA_0 and VREFINT (without PA_1), and work well to read the PA_0 and VREFINT.

Can any one help me to solve this problem ?