Hello NXP Team,
I am using the S32K312 controller and I would like to use the pin labelled ADC1_MA1 for reading a potentiometer voltage.
I understand that ADC1_MA1 is an ADC external multiplexer address output pin. However, I would like to confirm whether there is any possible configuration in SIUL2, ADC, or pin mux settings that allows this pin to be used as a normal ADC analog input.
My requirement is to connect a potentiometer wiper voltage, in the range of 0 V to 3.3 V, and read it through ADC1.
Could you please confirm:
- Is ADC1_MA1 physically connected to any ADC input channel/sample-and-hold circuit?
- Can this pin be configured as an ADC input through software?
- If it cannot be used as an ADC input, is there any recommended hardware workaround when the PCB is already designed with the potentiometer connected to this pin?
Thank you.
Best regards,
Esakki
Hi Esakki,
ADC1_MA1 is the ADC Mux Output, a digital pin, and its direction is output. The function of this pin is described in "S32K3 ADC Use of external channels".
The ADC1_MA1 pin has no Direct Signals and cannot be used as an ADC input. Only pins with an ADC listed in the Direct Signals section can be used as ADC inputs.
![PTB24 ADC1_MA[1] no Direct Signals.png](https://community.nxp.com/t5/image/serverpage/image-id/391873iB9C3CC1561A00096/image-size/large?v=v2&px=999 "PTB24 ADC1_MA[1] no Direct Signals.png")
![PTB24 ADC1_MA[1] ADC Mux Output.png](https://community.nxp.com/t5/image/serverpage/image-id/391874iFF7AD75F232C33FC/image-size/large?v=v2&px=999 "PTB24 ADC1_MA[1] ADC Mux Output.png")
Unfortunately, there are no other reliable solutions, and it is recommended to modify the hardware circuitry.
Best Regards,
Robin