CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *J
46
Example Projects
5.2.3.3.3
RTD
shows the RTD temperature calculation flowchart.
Figure 5-10. RTD Flowchart
The flowchart involves converting RTD resistance to temperature. The RTD calculator component is
used for this conversion. The RTD component chooses the correct polynomial order based on your
accuracy requirements.
Start
Set IDAC to source 128 uA
current
End
Connect IDAC current mux to
calibration reference resistor and
measure voltage V
1
Read voltage across
calibration resistor zero
current for CDS
CDS and filter V
1
Connect IDAC current mux
channel to RTD and
measure voltage V
2
Read voltage across RTD
sensor at zero current for CDS
CDS and filter V
2
Measure RTD resistance from V
2
and V
1
Calculate temperature from the
RTD resistance