SBAU378A September 2021 – January 2022 ADS1148 , ADS1248
Figure 3-20 shows how to connect a 4-wire RTD using a high-side RREF configuration to J6.
Figure 3-20 also shows that for this RTD configuration, the RTD is connected to REFN1, RTD_A, RTD_B, and RTD_C. Additionally, jumpers JP5 and JP6 are connected whereas jumpers JP3 and JP4 are disconnected. Finally, the AIN1 pin on the ADS1x48 is configured to be a current source and the measurement is taken between AIN2 and AIN3. Table 3-5 summarizes the necessary connections and ADC configuration settings.