Bench measurements demonstrate that the I_LKG current is not continuously present on the INx pin. Instead, it is injected only when the internal MUX actively connects a specific INx channel to the ADC or comparator circuitry. This transient lasts for the duration of the configured sampling window—approximately T_adc when the channel is assigned to ADC mode, or approximately T_comp when assigned to comparator mode. Outside of these windows, the INx pin is electrically isolated from the internal ADC front-end.

Figure 3-1 and Figure 3-2 show oscilloscope captures of the INx pin voltage during the sampling window in ADC mode and comparator mode, respectively. In both cases, the wetting current is set to 0 mA, and the voltage excursion at the INx pin is caused entirely by the transient MUX-connection current charging the external and parasitic capacitance on the INx node. Critically, switching between ADC and comparator configuration changes only the pulse width of the observed voltage spike, not its amplitude, which confirms that this phenomenon is associated with the MUX and internal ADC circuitry rather than with any external wetting current source.