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CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *J 61
Example Projects
5.3.3.2 Component Configuration
As mentioned earlier, you need to take a total of 15 different ADC readings for the seven measure-
ments. Each of these readings requires different ADC configurations to achieve the maximum
dynamic range out of the ADC. For example, the 3.3 V and 5 V rail require the ADC to have a large
input voltage range. The same range yields imprecise results for the 20 mV input. To accommodate
these different sensors, four different ADC configurations are used. The ADC configurations are
switched in the ADC interrupt.
Table 5-12 shows the 15 ADC readings and their ADC voltage range.
Table 5-12. ADC Reading and Voltage Range
Measurement ADC Reading ADC Input Range
20 mV Input 20 mV Input ± 0.064 V
RTD
RTD ± 0.256 V
RTD CDS ± 0.256 V
Reference Resistor ± 0.256 V
Reference Resistor CDS ± 0.256 V
100 mV Input 100 mv Input ± 0.256 V
Diode
Voltage Across Diode Current 1 ± 1.024 V
Voltage Across Diode Current 2 ± 1.024 V
Reference Resistor Current1 ± 0.064 V
Reference Resistor Current2 ± 0.064 V
Reference Resistor CDS ± 0.064 V
DS600 IC Temp Sensor
DS600 Voltage ± 1.024 V
DS600 CDS ± 1.024 V
3.3 V Rail 3.3 V Rail ± 6.144 V
5 V Rail 5 V Rail ± 6.144 V