Tool/software:
Here are my PCB document and register configuration: #define ADS1220_CONFIG_REG0_PT1000 0x60 // AINP=AIN0, AINN=AIN1, PGA=1, PGA ON #define ADS1220_CONFIG_REG1_PT1000 0x04 // DR=20SPS, NORMAL MODE, CONTINUOUS CONVERSION #define ADS1220_CONFIG_REG2_PT1000 0x56 // EXTERNAL REFERENCE (REFP0, REFN0), 50Hz/60Hz REJECTION, IDAC=1000μA #define ADS1220_CONFIG_REG3_PT1000 0x70 // IDAC1=AIN2, IDAC2=AIN3 I used the formula Vref = 2 · I_IDAC1 · R_REF to calculate the reference voltage, and the result is 2V. However, when I measured both sides of R43 with a multimeter, the reading was 1.519V.
Despite this discrepancy, using the measured 1.519V as the reference voltage for ADC conversion yielded accurate results.
