CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *J
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Example Projects
Thermistor
A thermistor can be simulated by a potentiometer. By varying the potentiometer resistance, you can
simulate temperatures in the whole temperature range of the thermistor. A potentiometer resistance
is used to provide resistance in the whole thermistor temperature range; the thermistor temperature
measured by PSoC is noted. The resistance is also measured by an accurate multimeter and the
expected temperature is calculated using the Steinhart-Hart equation.
shows the results.
RTD
An RTD can be simulated by a potentiometer. By varying the potentiometer resistance, you can sim-
ulate the temperature in the whole temperature range of the RTD. A potentiometer is used to provide
resistances in the whole RTD temperature range; the RTD temperature measured by PSoC is noted.
1
0.666
16.7
16.7
0
2
1.754
43.46
43.4
0.1
3
2.58
63.5
63.5
0
4
3.663
89.5
89.4
0.1
5
4.712
114.9
114.9
0
10
9.582
235.9
235.8
0.1
20
19.58
475
475
0
30
28.76
691.2
691.1
0.1
40
39.54
955.75
955.8
–0.1
50
49.816
1227
1226.9
0.1
Table 5-4. Thermistor Test Results
Resistance in ohms
(Multimeter Measurement)
Expected Temperature
Measured Temperature
(°C)
Signal Chain Error
(°C)
99318.0
–27.6
–27.60
0.00
32593.0
–4.0
–4.1
–0.10
12135.0
19.9
19.9
0.00
10000.0
25.0
25
0.00
6951.0
35.0
35
0.00
4230.0
49.5
49.6
0.10
3021.0
60.0
60
0.00
2065.0
72.6
72.7
0.10
1260.0
90.2
90.2
0.00
977.6
99.9
99.9
0.00
800.8
107.8
107.8
0.00
549.5
123.5
123.6
0.10
419.3
135.6
135.5
–0.10
308.3
150.1
150
–0.10
270.0
156.6
156.5
–0.10
189.3
175.1
175
–0.10
122.7
199.7
199.5
–0.20
Table 5-3. Thermocouple Test Results
Simulated thermo-emf
(mV)
Voltage read by
multimeter (mV)
Expected
temperature (°C)
Obtained
Temperature (°C)
Error (°C)
