MSPM0G1507: Can the difference between OPA0 IN0+ and OPA0 IN0- be acquired via ADC?

K.Z

Part Number: MSPM0G1507
Other Parts Discussed in Thread: SYSCONFIG, MSPM0G3507

Tool/software:

Hi All,

I want to acquire the difference between OPA0 IN0+ and OPA0 IN0- as an AD value using the MSPM0G1507.
Whether due to incorrect SysConfig settings or not, the acquired AD value comes out as 0xFFF.
Is this inherently impossible?

Setting NSEL to RTOP allows acquiring the voltage applied to the pin specified by PSEL as an ADC value, so I believe the ADC configuration is possible.

Looking at opa_general_purpose_rri_LP_MSPM0G3507_nortos_ticlang, it seems possible to output the difference to PA16.
Is it not possible to output it as an AD value?

1) I want to acquire the voltage difference applied to the OPA0 IN0+ (PA26) and OPA0 IN0- (PA27) terminals as an AD value.
DC 1.6V is applied to OPA0 IN0+, and DC 1.2V is applied to OPA0 IN0-.
With the following settings, the AD value appears to be underflowing and reads as 0xFFF.