32.1.2 Channel Selection
The ADPCH register determines which channel is connected to the Sample-and-Hold circuit for conversion. When switching channels, it is recommended to have some acquisition time (ADACQ register) before starting the next conversion. Refer to 32.2 ADC Operation for more information.
The channel selections are available using the PCH bits in the ADPCH register.
Important: To reduce the chance of measurement error, it is
recommended to discharge the Sample-and-Hold capacitor when switching between ADC channels
by starting a conversion on a channel connected to VSS and terminating the
conversion after the acquisition time has elapsed. If the ADC does not have a dedicated
VSS input chnnel, the VSS selection through the DAC output channel
can be used. If the DAC is in use, a free input channel can be connected to VSS,
and can be used in place of the DAC.