Texas Instruments ADS1x48EVM, Руководство пользователя, Страница: 21 / 48

3.5.3.3 Connecting a 3-Wire RTD Using One IDAC and a Low-Side R
REF
to J6 on the ADS1x48EVM
Figure 3-15 shows how to connect a 3-wire RTD using one IDAC and a low-side R
REF
configuration to J6.
REFP1
REFN1
AIN0
REFP1
REFN1
R
T
D
RTD_A
RTD_B
RTD_C
IEXC1
AIN3
AIN2
JP3
JP4
JP5
IEXC2 IEXC2
AIN1
IDA C
JP6
Figure 3-15. Connection Diagram for a 3-Wire RTD Using One IDAC and a Low-Side R
REF
Figure 3-15 also shows that for this RTD configuration, the RTD is connected to REFP1, RTD_A, and RTD_B.
Additionally, jumpers JP3 and JP4 are connected whereas jumpers JP5 and JP6 are disconnected. Moreover,
the IEXC1 current source is enabled. Finally, this specific configuration requires two measurements for lead-
wire cancellation: the first is between AIN3 and AIN2, and the second is between AIN2 and AIN1.
Table 3-5
summarizes the necessary connections and ADC configuration settings.
www.ti.com ADS1x48EVM Overview
SBAU378A – SEPTEMBER 2021 – REVISED JANUARY 2022
Submit Document Feedback
ADS1x48EVM Evaluation Module 21
Copyright © 2022 Texas Instruments Incorporated