The input multiplexer controls which signals are routed to the positive and negative PGA inputs of the ADC2y channel in each sequence step. Configure the input multiplexer using the SEQ2y_STEPn_CH_P[3:0] and SEQ2y_STEPn_CH_N bits.

The input multiplexer allows the following inputs to be connected to the PGA:

• Any of the eight analog inputs, V0y to V7y, in single-ended measurement configuration when AGNDy is selected as the negative multiplexer channel.
• Any of the seven analog inputs, V0y to V6y, in single-ended measurement configuration when V7y is selected as the negative multiplexer channel and connected to AGNDy externally.
• Any of the seven analog inputs, V0y to V6y, in pseudo-differential measurement configuration when V7y is selected as the negative multiplexer channel. Connect a positive bias voltage to V7y in this case, either using an external bias voltage or the internal common-mode voltage of the VCMy buffer.
• Internal temperature sensor, TSy.
• Internal short to AGNDy. Use this setting for self-offset calibration of the ADC2y channel.
• DC test signal provided by the Test DAC of the other section.
• Attenuated signals of the various supply voltages (APWR, DPWR, AVDD, IOVDD, and DVDD).

Whenever a signal other than an analog input is selected as the positive multiplexer input, the analog inputs are disconnected from the PGA and AGNDy is selected automatically as the negative multiplexer input. Figure 9-7 illustrates a diagram of the ADC2A input multiplexer.

Figure 9-7 ADC2A Input Multiplexer