CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *J
8
Introduction
Note
: The temperature sensor comparison chart does not include values for DS600 IC because it is
used for cold junction compensation for the thermocouple; it is not intended for use as an onboard
temperature sensor.
This kit includes three example projects, divided into project areas based on end applications. Each
project area contains examples for the CY8CKIT-030, CY8CKIT-050, and CY8CKIT-001
development kits. The CY8CKIT-030 DVK contains a PSoC 3 (8051 core) and the CY8CKIT-050
DVK contains a PSoC 5LP (ARM Cortex-M3); both support high-performance analog applications.
The CY8CKIT-001 DVK can be used to develop solutions for PSoC 1 (M8C proprietary core),
PSoC 3, or PSoC 5LP (ARM Cortex 3). The included example projects support PSoC 3 (8051) and
PSoC 5LP (ARM Cortex-M3).
The Tempsense example project provided with the kit supports most temperature sensing
applications. It provides a high-performance temperature sensing example by using the ADC in 20-
bit mode and implementing a high-precision linearization algorithm. It includes a resistance
temperature detector (RTD), thermocouple, thermistor, two temperature diodes, and an IC
temperature sensor. You can evaluate and compare sensor performance. Complete interface and
output signal correction solutions can be developed for each type of temperature sensor. With the
20-bit ADC of the PSoC, it is possible to obtain a 0.1-°C resolution easily with all four sensors. The
accuracy varies in each case depending on the method of measurement and the sensor used. See
the
for details.
The Sequenced ADC example project includes three temperatures (RTD, temperature diode, and IC
temperature sensor) as well as millivolt and voltage inputs. This project can be used for sensing
applications that require temperature measurement (such as RTD) as well as other types of voltage
output sensors. It can also be used for system monitoring applications requiring temperature (usually
Table 1-1. Temperature Sensor Comparison
Parameter
RTD
Thermocouple
Thermistor
Diode
Temperature range
(°C)
–200 to +850
–250 to +2350
–100 to +300
–50 to +150
Sensitivity at 25 °C 0.387
Ω
/°C
40
μ
V/°C (K-type)
416
Ω
/°C
250
μ
V /°C
Accuracy
High
Medium to High
Medium
Low
Linearity
Good
Fair
Poor
Good
Typical cost (US $) $3–$80
$3–$15
$0.2–$10
<$0.2
Typical distance of
sensing
Surface mount for
onboard temperature.
3- and 4-wire up to a
few hundred meters
<100 meters
Surface mount for
onboard temperature.
Leaded for <1 meter
Onboard temper-
ature
Resource require-
ment
Excitation current,
amplifier, ADC, refer-
ence resistor
Amplifier, ADC, volt-
age reference, and
another temperature
sensor for cold junc-
tion
Excitation current,
ADC, reference resis-
tor
Excitation cur-
rent, amplifier,
ADC
Response time
Slow
Fast
Fast
Slow
Computational
complexity (best
possible accuracy)
High
Very high
Very high
Medium
Cypress applica-
tion note
