
3.5.3.6 Connecting a 3-Wire RTD Using Two IDACs and a High-Side R
REF
to J6 on the ADS1x48EVM
shows how to connect a 3-wire RTD using two IDACs and a high-side R
REF
configuration to J6.
REFP1
REFN1
AIN0
REFP1
REFN1
RTD_A
RTD_B
RTD_C
IEXC1
AIN3
AIN2
JP3
JP4
JP5
R
T
D
IEXC2
IEXC2
AIN1
IDA C
JP6
Figure 3-18. Connection Diagram for a 3-Wire RTD Using Two IDACs and a High-Side R
REF
also shows that for this RTD configuration, the RTD is connected to REFN1, RTD_A, and RTD_B.
Additionally, jumpers JP4, JP5, and JP6 are connected whereas jumper JP3 is disconnected. Finally, the
AIN1 pin on the ADS1x48 is configured to be a current source and is used in conjunction with the IEXC1
current source, while the measurement is taken between AIN0 and AIN2.
summarizes the necessary
connections and ADC configuration settings.
ADS1x48EVM Overview
24
ADS1x48EVM Evaluation Module
SBAU378A – SEPTEMBER 2021 – REVISED JANUARY 2022
Copyright © 2022 Texas Instruments Incorporated