CY8CKIT-025

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Please continue to use the ordering part numbers listed in the datasheet for ordering. www.infineon.com CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide Doc. # 001-65791 Rev. *K Cypress Semiconductor 198 Champion Court San Jose, CA 95134-1709 Phone (USA): 800.858.1810 Phone (Intnl): 408.943.2600 www.cypress.com Copyrights Copyrights © Cypress Semiconductor Corporation, 2011–2017. This document is the property of Cypress Semiconductor Corporation and its subsidiaries, including Spansion LLC ("Cypress"). This document, including any software or firmware included or referenced in this document ("Software"), is owned by Cypress under the intellectual property laws and treaties of the United States and other countries worldwide. Cypress reserves all rights under such laws and treaties and does not, except as specifically stated in this paragraph, grant any license under its patents, copyrights, trademarks, or other intellectual property rights. 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You shall indemnify and hold Cypress harmless from and against all claims, costs, damages, and other liabilities, including claims for personal injury or death, arising from or related to any Unintended Uses of Cypress products. Cypress, the Cypress logo, Spansion, the Spansion logo, and combinations thereof, PSoC, CapSense, EZ-USB, F-RAM, and Traveo are trademarks or registered trademarks of Cypress in the United States and other countries. For a more complete list of Cypress trademarks, visit cypress.com. Other names and brands may be claimed as property of their respective owners. CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 2 Contents Safety Information 1. Introduction 1.1 1.2 1.3 1.4 1.5 5 7 Kit Contents .................................................................................................................9 PSoC Creator™.........................................................................................................11 Getting Started...........................................................................................................11 Additional Learning Resources..................................................................................11 1.4.1 Beginner Resources.......................................................................................11 1.4.2 Engineers Looking for More ...........................................................................11 1.4.3 Learn from Peers ...........................................................................................11 1.4.4 More Code Examples.....................................................................................12 1.4.5 Technical Support...........................................................................................13 Document Conventions .............................................................................................14 2. Software Installation 15 3. Kit Operation 18 3.1 3.2 3.3 3.4 Kit Overview...............................................................................................................18 Kit Connections..........................................................................................................18 Temperature Sensors ................................................................................................21 3.3.1 Thermocouple ................................................................................................21 3.3.2 Thermistor ......................................................................................................21 3.3.3 RTD................................................................................................................22 3.3.4 Diode..............................................................................................................22 Prototype Boards .......................................................................................................23 4. Hardware 4.1 4.2 4.3 4.4 4.5 24 System Block Diagram and Theory of System Operation .........................................24 Thermocouple............................................................................................................24 Thermistor..................................................................................................................25 RTD ...........................................................................................................................26 Diode .........................................................................................................................28 CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 3 Contents 5. Example Projects 5.1 5.2 5.3 5.4 A. Appendix A.1 A.2 A.3 A.4 30 Overview....................................................................................................................30 5.1.1 Migrating Projects to use with CY8CKIT-050 and CY8CKIT-010 ...................31 Tempsense ................................................................................................................32 5.2.1 Project Description .........................................................................................32 5.2.2 Project Operation ...........................................................................................33 5.2.3 Project Details ................................................................................................40 Sequenced ADC ........................................................................................................52 5.3.1 Project Description .........................................................................................52 5.3.2 Project Operation ...........................................................................................52 5.3.3 Project Details ................................................................................................58 Thermal Management................................................................................................68 5.4.1 Project Description .........................................................................................68 5.4.2 Project Operation ...........................................................................................70 5.4.3 Project Details ................................................................................................75 83 Schematic ..................................................................................................................83 Board Layout .............................................................................................................84 A.2.1 PDC-09802 Top .............................................................................................84 A.2.2 PDC-09802 Bottom ........................................................................................84 Bill of Materials (BOM) ...............................................................................................85 Regulatory Compliance Information ..........................................................................85 Revision History CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 86 4 Safety Information Regulatory Compliance The CY8CKIT-025 is intended for use as a development platform for hardware or software in a laboratory environment. The board is an open system design, which does not include a shielded enclosure. This may cause interference to other electrical or electronic devices in close proximity. In a domestic environment, this product may cause radio interference. In this case, you may be required to take adequate prevention measures. Also, the board should not be used near any medical equipment or RF devices. Attaching additional wiring to this product or modifying the product operation from the factory default may affect its performance and cause interference with other apparatus in the immediate vicinity. If such interference is detected, suitable mitigating measures should be taken. The CY8CKIT-025 as shipped from the factory has been verified to meet with requirements of CE as a Class A product. The CY8CKIT-025 contains electrostatic discharge (ESD) sensitive devices. Electrostatic charges readily accumulate on the human body and any equipment, and can discharge without detection. Permanent damage may occur on devices subjected to high-energy discharges. Proper ESD precautions are recommended to avoid performance degradation or loss of functionality. Store unused CY8CKIT-025 boards in the protective shipping package. End-of-Life/Product Recycling This kit has an end-of-life cycle five years from the date of manufacturing mentioned on the back of the box. Contact your nearest recycler for discarding the kit. CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 5 Safety Information General Safety Instructions Electrostatic Discharge Protection ESD can damage boards and associated components. Cypress recommends that you perform procedures only at an ESD workstation. If one is not available, use appropriate ESD protection by wearing an antistatic wrist strap attached to chassis ground (any unpainted metal surface) on your board when handling parts. Handling Boards CY8CKIT-025 boards are sensitive to ESD. Hold the board only by its edges. After removing the board from its box, place it on a grounded, static free surface. Use a conductive foam pad if available. Do not slide board over any surface. CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 6 1. Introduction Thank you for your interest in PSoC solutions for temperature sensing. The CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit (EBK) together with the example projects provide complete solutions demonstrating PSoC-based temperature sensing. The CY8CKIT-025 board connects with the CY8CKIT-030 PSoC 3 Development Kit (DVK), CY8CKIT050 PSoC 5LP Development Kit, or the CY8CKIT-001 PSoC Development Kit. The kit supports temperature measurement using four temperature sensors: ■ ■ ■ ■ Thermocouple Thermistor Resistive Temperature Detector (RTD) Diode Note: The TempSense example project outputs one more temperature value read from the DS600 IC. This is used for cold junction compensation for the thermocouple and not intended as an option for the onboard temperature sensor. The four sensors have their own advantages and limitations. The choice of a sensor for an application depends on the cost, accuracy required, and temperature measurement range. Thermocouples measure temperatures in a wide range, from –250 °C to 2300 °C. However, the voltage change is not linear and takes more CPU cycles for temperature computation. Thermocouples require another temperature sensor, such as the thermistor, diode, or RTD, to measure the cold junction temperature. The DS600 IC or the thermistor can be used for cold junction compensation of the thermocouple. A thermistor, diode, or RTD cannot measure temperatures greater than 850 °C. Thermocouples have a very good response time. Thermistors have a highly nonlinear curve and take more CPU cycles for temperature computation. They measure temperature in the range –100 °C to 200 °C. Thermistors have a good response time and they are less expensive when compared to RTDs and thermocouples. RTDs have a linear and repeatable resistance variation with temperature, making it easier to compute temperature accurately. They measure temperature from –200 °C to 850 °C. RTDs are expensive due to their linearity and accuracy. RTDs have a lower response time compared to a thermistor or thermocouple. Diodes are the cheapest sensors for temperature measurement. They measure temperature in the range –50 °C to 150 °C. Accurate temperature measurement is difficult with a diode. Table 1-1 shows a comparison among the four sensors. CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 7 Introduction Table 1-1. Temperature Sensor Comparison Parameter RTD Thermocouple Thermistor Diode Temperature range –200 to +850 (°C) –250 to +2350 –100 to +300 –50 to +150 Sensitivity at 25 °C 0.387 Ω/°C 40 μV/°C (K-type) 416 Ω/°C 250 μV /°C Accuracy High Medium to High Medium Low Linearity Good Typical cost (US $) $3–$80 Fair Poor Good $3–$15 $0.2–$10 Device Selector). If the CY8CKIT-001 project is being updated to be used with the PSoC 5LP processor module, you must also change the CMOD pin mapping from P2_7 to pin 15_5. To print floating point variables on the LCD, set the ‘Use newlib-nano Float Formatting’ parameter to True under Project > Build Settings > Linker as shown in Figure 5-1 and change the Heap Size to 0x200 in the System tab in the .cydwr file as shown in Figure 5-2. Figure 5-1. Build Settings Figure 5-2. System Tab CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 31 Example Projects The following sections provide a detailed description of these example projects. 5.2 Tempsense This example project demonstrates high-precision, high-accuracy, multi-channel temperature sensing using PSoC. 5.2.1 Project Description This project displays the temperature measured using a thermocouple, IC sensor, thermistor, RTD, and two diodes. It also provides steps to calibrate the RTD, diode, and IC. The user interface of this example is controlled by two CapSense® buttons, a CapSense slider, two mechanical push buttons, and a character LCD. When the example project for CY8CKIT-030 is programmed, the LCD displays a welcome message for one second. It then displays the temperature from the thermocouple, which is the first item in the user selectable menu. CapSense buttons P5_5 and P5_6 act as the scroll down and scroll up menu buttons, respectively. A mechanical switch connected to P6_1 is used to proceed through various calibration steps. A CapSense slider is used to set the calibration temperature. The menu has the following items: ■ Thermocouple temperature display ■ IC temperature display ■ Thermistor temperature display ■ RTD temperature display ■ Diode1 temperature display ■ Diode2 temperature display ■ Simultaneous temperature display labels (see Figure 5-3) ■ Simultaneous temperature display from all 6 sensors (see Figure 5-4) ■ Calibrate RTD temperature ■ Calibrate Diode1 temperature ■ Calibrate Diode2 temperature ■ Calibrate IC sensor temperature In the simultaneous display, the first row displays the temperature of the thermocouple, IC, and thermistor. The second row displays the temperature of the RTD, diode 1, and diode2, as shown in Figure 5-4. Figure 5-3. Simultaneous Temperature Display Labels CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 32 Example Projects Figure 5-4. Simultaneous Temperature Display for All Six Sensors Thermocouple IC RTD Diode1 5.2.2 Project Operation 5.2.2.1 Hardware Connections Thermistor Diode2 The kit includes example projects for the CY8CKIT-001 DVK, CY8CKIT-030 DVK, and CY8CKIT-050 DVK hardware platforms. The pin mapping for CY8CKIT-030 and CY8CKIT-050 are identical; follow the instructions provided for CY8CKIT-030 PSoC 3 DVK for CY8CKIT-050 PSoC 5LP DVK as well. The main difference between the examples for the CY8CKIT-001 and CY8CKIT-030 platforms is the PSoC pin mapping. The project provided for the CY8CKIT-001 PSoC DVK can be used with both PSoC 3 and PSoC 5LP. See Migrating Projects to use with CY8CKIT-050 and CY8CKIT-010 on page 31 for more details. 5.2.2.1.1 CY8CKIT-030 PSoC DVK 1. Plug the PSoC Precision Analog Temperature Sensor EBK to port E of the CY8CKIT-030 DVK. 2. No jumper wires are required for the PSoC 3 DVK examples because the mechanical buttons are hard-wired to GPIOs. Ensure that the LCD included with the PSoC 3 DVK is attached. 3. Set VDDD and VDDA to 3.3 V using J10 and J11. 4. In the CY8CKIT-025 EBK, choose appropriate jumper settings for internal sensors; see the Kit Operation chapter on page 18. Note: When using the CY8CKIT-025 EBK with CY8CKIT-050 PSoC 5LP DVK, remove the jumpers from J43 and J44 on PSoC 5LP DVK. CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 33 Example Projects 5.2.2.1.2 CY8CKIT-001 PSoC DVK 1. Plug the PSoC Precision Analog Temperature Sensor EBK to port A of the CY8CKIT-001 DVK. 2. In the pin header/breadboard area of the CY8CKIT-001 base board, use jumper wires to make the following connections: a. SW1 to P1_7 b. SW2 to P0_7 3. Set the system to run at 3.3 V using SW3; set J6 VDD DIG and J7 VDD ANLG to VDD = 3.3 V. CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 34 Example Projects 4. Ensure that the LCD included with the PSoC DVK is attached and the LCD power jumper (J12) is in the ON position. 5. In the CY8CKIT-025 EBK, choose appropriate jumper settings for internal sensors; see the Kit Operation chapter on page 18. 5.2.2.2 Run Tempsense Example Firmware 5.2.2.2.1 CY8CKIT-030 PSoC 3 DVK The steps to run the example firmware on CY8CKIT-030 are: 1. Attach a USB cable from the PC to the PSoC 3 DVK program/debug USB port (use J1, the USB connector closest to the corner of the board). 2. Open the Tempsense_030_050 project using PSoC Creator and select Debug > Program to program the PSoC. 3. Detach the USB cable and connect hardware according to Hardware Connections on page 33. 4. Attach the USB cable again from the PC to the PSoC 3 DVK program/debug USB port (use J1). 5. Press the Reset (SW1) button on the PSoC 3 DVK to run the newly programmed firmware image. 6. On reset, the LCD displays a welcome message and the temperature reading from the thermocouple, which is the first item in the user selectable menu. SW2 can be used to toggle the cold junction compensation sensor between the IC (DS600) and thermistor. 7. Press CapSense button P5_5 to scroll down the menu and P5_6 to scroll up the menu. 8. Use SW2 to proceed through the calibration steps; see RTD Calibration on page 47. 9. Use SW3 to return to the previous step during calibration. 5.2.2.2.2 CY8CKIT-001 PSoC DVK The steps to run the example firmware on CY8CKIT-001 are: 1. Apply 12 VDC power to the PSoC DVK. 2. Attach the MiniProg3 device, first to a USB port on the PC and then to the PROG port on the CY8CKIT-009 PSoC 3/CY8CKIT-010 PSoC 5LP processor module. 3. Open the Tempsense_001 project using PSoC Creator and select Debug > Program to program the PSoC. 4. Disconnect power to the PSoC DVK and connect hardware according to Hardware Connections on page 33. 5. Power the PSoC DVK. 6. On reset, the LCD displays a welcome message and the temperature reading from the thermocouple, which is the first item in the user selectable menu. SW1 can be used to toggle the cold junction compensation sensor between the IC (DS600) and thermistor CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 35 Example Projects 7. Press CapSense button P0_5 to scroll down the menu and P0_6 to scroll up the menu. 8. Use SW1 to proceed through calibration steps; see RTD Calibration on page 47. 9. Use SW2 to return to the previous step during calibration. 5.2.2.3 Testing the Project For best results when testing temperature measurements, ensure that you have good thermal contact between the sensor and your reference thermometer. Also, make sure there is minimal air flow, which can result in temperature gradient. Sample test results are given in the following sections. 5.2.2.4 Expected Performance and Test Results This section explains the expected resolution and accuracy of the temperature displayed by all the sensors. 5.2.2.4.1 Accuracy The accuracy of the temperature displayed depends on the sensor and the signal chain. Sensor Each sensor has a tolerance, which is available in the datasheet provided by the sensor manufacturer. The tolerance indicates the error due to replacement of one sensor with another of the same part number. The tolerance of each onboard sensor is listed in Table 5-1. These numbers are from the respective sensor datasheets. Table 5-1. Temperature Sensor Tolerances Sensor Thermocouple 5SRTC-GG-K-20-36 Thermistor NCP18XH103F03RB RTD PTS080501B100RP100 Diode IC Tolerance Standard ASTM special limits of error 1.1 °C or 0.4%, whichever is higher 1% at 25 °C 1% B-value tolerance IEC Class B RTD (0.30 + 0.005T) °C – – Maximum Tolerance Error at 25 °C Maximum Tolerance Error at 100°C ± 1.1 °C ± 1.1 °C ± 0.4 °C ± 2 °C ± 0.43 °C ± 0.8 °C – ± 0.5 °C – ± 0.5 °C For diode, the ideality factor is the source of its tolerance. This number is generally not mentioned in the diode datasheet and must be determined experimentally. Diode ideality factor generally lies between 1 and 1.01. An ideality factor difference of 0.004 (using 1.008 instead of 1.004) causes an error of around 2 °C. See AN60590 - PSoC 3 and PSoC 5LP - Temperature Measurement with a Diode for more details on these calculations. Signal Chain Signal chain error includes the errors due to the ADC, IDAC, the calibration (reference) resistors and the measurement method. The resources used differ from sensor to sensor. The main sources of ADC error are its offset, gain error, and INL. Of these, the offset error is cancelled in all cases by correlated double sampling. ADC gain error is eliminated by using a precision reference resistor in thermistor and RTD. CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 36 Example Projects The main sources of IDAC error are its offset, gain error, and INL. The IDAC errors are completely removed by passing the IDAC current through a precise reference resistor and measuring the voltage across it. The reference resistor tolerance determines the error caused by it. A 0.1% reference resistance is used in both RTD and thermistor temperature measurements. The error component caused by the signal chain for each sensor is listed in Table 5-2. Table 5-2. Signal Chain Errors for PSoC 3 Sensor Thermocouple Thermistor RTD Diode Signal Chain Error Components ADC gain error, INL, cold junction IC sensor error (± 0.5 °C) ADC INL, reference resistor tolerance ADC INL, reference resistor tolerance ADC gain error, INL Typ/Max Error at 25 °C Max Error at 100 °C 0.1 / 2.1 2.2 0 / 0.05 0.1 / 0.5 0.3 / 2.6 0.6 0.9 3.8 Cypress application notes on each of the four sensors explain the signal chain errors in detail. 5.2.2.4.2 Resolution (peak to peak) The temperature measurement resolution is the minimum temperature increment possible. A 0.1 °C resolution is achieved on all sensors. A software IIR filter (see Sensor Output Filter on page 51) is applied on some sensors to achieve 0.1 °C resolution. The application notes associated with each sensor gives more details on how 0.1 °C resolution is achieved on each sensor. Generally, a small flicker is seen on the LCD temperature display. A small flicker of 0.2 °C on thermocouple readings, 0 °C on IC and thermistor, 0.1 °C on RTD, and 0.3 °C on diode at a very small rate has been observed in the example projects. It can be reduced by additional filtering at the cost of temperature settling time. The IIR filter can be changed in firmware, as shown in Sensor Output Filter on page 51. 5.2.2.4.3 Test Results This section shows the test results on the sample board. Wherever possible, measurement techniques are used to identify the signal chain performance of PSoC. Thermocouple Thermocouple input can be simulated by a millivolt source. This eliminates any error due to thermocouple tolerance and allows you to test the signal chain in the whole temperature range without a heat source. A millivolt source is fed to the thermocouple inputs and the cold junction temperature is forced to 0 °C in the example project. The temperature shown by PSoC is noted and the voltage input is measured using an accurate voltmeter; the temperature corresponding to that voltage is calculated using NIST tables. The expected results and actual results are listed in Table 5-3. Table 5-3. Thermocouple Test Results Simulated thermo-emf (mV) Voltage read by multimeter (mV) Expected temperature (°C) Obtained Temperature (°C) Error (°C) –5 –4.695 –141 –141.1 0.1 –4 –3.666 –103.7 –103.7 0 –3 –2.575 –69.6 –69.5 –0.1 –2 –1.741 –45.9 –45.7 –0.2 –1 –0.654 –16.77 –16.7 –0.1 0 0 0 0 0 CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 37 Example Projects Table 5-3. Thermocouple Test Results Simulated thermo-emf (mV) Voltage read by multimeter (mV) Expected temperature (°C) Obtained Temperature (°C) 1 2 0.666 16.7 16.7 0 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 Error (°C) 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. Table 5-4 shows the results. Table 5-4. Thermistor Test Results Resistance in ohms Expected Temperature (Multimeter Measurement) 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 RTD An RTD can be simulated by a potentiometer. By varying the potentiometer resistance, you can simulate 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. CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 38 Example Projects The resistance is also measured by an accurate multimeter and the expected temperature is calculated using Callender Van Dusen equation. Table 5-5 shows the results . Table 5-5. RTD Test Results Resistance in Ohms (Multimeter Measurement) Expected Temperature (°C) Measured Temperature (°C) Temp Measure Error (Signal Chain) (°C) 79.85 –51.1 –51.3 –0.20 100.06 0.2 0.2 0.00 110.76 27.6 27.7 0.10 120.25 52.2 52.1 –0.10 133 85.5 85.3 –0.20 138.5 100.0 100 0.00 150 130.4 130.3 –0.10 194.4 250.8 251 0.20 280.85 499.8 500 0.20 315.7 606.2 606.2 0.00 371.8 787.0 787.3 0.30 Diode Diode temperature accuracy is tested in a temperature forcing system by forcing a specific temperature and comparing the diode results with those of a standard thermometer. The standard microthermal thermocouple thermometer, with an accuracy of 1.3 °C (including thermocouple probe error), is used. Table 5-6 shows the results. Table 5-6. Diode Test Results Temperature Measured using Standard Thermometer Diode Measured Temperature (with PSoC) (°C) 0.8 1.2 0.4 6.2 5.6 –0.6 17 16.1 –0.9 22 21 –1 30 29.3 –0.7 75.3 74.7 –0.6 99.5 99.4 –0.1 Diode Temperature Error (°C) DS600 IC Sensor The IC sensor signal chain accuracy is tested by measuring the voltage output by the IC at various temperatures and calculating the expected temperature and comparing it to the temperature displayed by PSoC. Sample test results at a few temperature points are shown in Table 5-7. Table 5-7. IC Sensor Test Results IC Output Voltage (mV) 640.32 Expected Temperature (°C) Observed Temperature (°C) Error (°C) 20.4 20.4 0.0 660.34 23.5 23.5 0.0 702.22 30.0 30 0.0 733.73 34.8 34.8 0.0 CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 39 Example Projects 5.2.2.4.4 Simultaneous Temperature Display of all Six Sensors The sensor-to-sensor variation in temperature is 0.5 °C to 1.1 °C without calibration. The signal chain can add additional error. Remember the following thermal considerations to understand the temperature difference between the sensors in the simultaneous display of six temperatures. ■ The thermocouple measures the air temperature; the RTD and thermistor measure the board temperature; the IC measures the temperature of the exposed pad below it; and diodes are screwed on to the board although they hang in the air. ■ Because the thermocouple measures the air temperature, it is about a degree Celsius lower than the board at room temperature. Place the tip of the thermocouple on the board and you will see the thermocouple temperature rise by a degree. ■ Place the board in the sun; you will note that the temperature display shown by the onboard sensors slowly rise. In tropical regions, you can see the board temperature rise to greater than 50 °C, while the thermocouple temperature will be around 35 °C to 37 °C. ■ The IC sensor has a thermal pad underneath it. Ideally, it is expected to be isothermal with the cold junction. Ensuring an isothermal connection requires providing good thermal contact between the thermocouple cold junction and the exposed IC pad. If the thermal contact is not provided, having the cold junction IC very close to the cold junction terminals is sufficient. The temperature difference between the cold junction terminals and the IC pad will not be more than 0.5 °C. Most thermocouple applications do not demand high accuracy and it is sufficient to have the cold junction IC very close to the cold junction. The IC temperature is about 0.3 °C to 0.5 °C lower than the RTD and thermistor temperature because the exposed pad underneath the IC is connected to ground. This is an offset error. This offset error can be eliminated by performing an offset correction, as shown in IC Calibration on page 50. Apart from the above thermal considerations, the sensor and bias resistor tolerances should determine the sensor temperature. Typically, RTD and thermistor temperatures are within about 0.3 °C of each other; IC temperature and diode temperature is within about 0.5°C lower than the thermistor temperature; and thermocouple temperature is about 1 °C to 2 °C lower than the thermistor temperature. 5.2.2.4.5 CY8CKIT-001 PSoC DVK Thermistor Temperature The CY8CKIT-025 connects to the Port A connector on the CY8CKIT-001. Through this connection, the resistor/thermistor network connects to pin 5_0. On PSoC port pins 0_0, 0_1, 3_6, and 3_7 connect directly to the opamp output. Thus, there is no direct connection from an opamp to the thermistor/resistor network, which is connected to pin 5_0. Therefore, an unbuffered VDAC is used to supply the required voltage for the thermistor/resistor network. Due to internal routing this connection has some parasitic resistance, which causes a voltage drop. The ADC measures this voltage drop and compensates. However, thermistor measurement on CY8CKIT-001 may result in higher error up to 0.5 °C. For details on internal analog routing, see AN58827 - PSoC 3 and PSoC 5LP Internal Analog Routing Considerations. 5.2.3 Project Details 5.2.3.1 Project Schematic Figure 5-5 shows the PSoC Creator schematic of the project. An eight-channel ADC is used to sense the six sensors. The IDAC has four channels to provide excitation to the RTD and the diodes. Whenever IDAC channel 2 is connected, the IDAC output flows through the diode connected transistor Q1, Pin 3_7 and to ground. The ground connection is provided on the pin in firmware. PSoC's pin structure allows easy connection to the ground. CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 40 Example Projects Figure 5-5. PSoC Creator Top Design CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 41 Example Projects 5.2.3.2 Component Configuration 5.2.3.2.1 ADC Configuration Settings The ADC is configured in 20-bit mode for all sensors except the thermistor, where it is configured in 16-bit mode. Figure 5-6 shows the configuration used. Figure 5-6. ADC Configuration The ADC Buffer Mode is set to Level Shift because many of the voltages being read are near VSS; this setting yields better ADC results for signals near VSS. 5.2.3.2.2 IDAC Configuration The IDAC is configured in the 0 to 255 µA-range. The IDAC is used for RTD and diode temperature measurements. The IDAC data register value is modified in firmware, as required for each of these temperature measurements. CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 42 Example Projects Figure 5-7. IDAC Configuration 5.2.3.3 Firmware Description and Flowchart The temperature calculation flowchart for each sensor and the flowchart for calibrating RTD and diode are explained in this section. A single point calibration is provided for RTD and diode. 5.2.3.3.1 Thermocouple Figure 5-8 illustrates the steps involved in thermocouple temperature measurement. This flowchart involves conversion of voltage to temperature and vice versa. The conversion is done using thermocouple calculator component, which in turn uses the polynomial provided by NIST. The mathematical conversion results in an error less than 0.07 °C. The example project uses a K-type thermocouple. The component supports all thermocouple types and provides application programming interfaces (APIs) for voltage to temperature conversion and vice versa. IC (DS600) or thermistor can be used for cold junction compensation. CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 43 Example Projects Figure 5-8. Thermocouple Flowchart Start Read Vssa Ref voltage for correlated double sampling (CDS) Read cold junction (CJ) voltage Convert CJ voltage to CJ temperature Convert CJ temperature to CJ compensation voltage. Read hot junction voltage, perform CDS and filter Add hot junction voltage to CJ compensation voltage Convert voltage to temperature END CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 44 Example Projects 5.2.3.3.2 Thermistor Figure 5-9 shows the thermistor temperature calculation flowchart. Figure 5-9. Thermistor Flowchart Start Read Vssa Ref voltage for CDS Read voltage across thermistor reference resistor (Vref) and perform offset cancellation(CDS) Read voltage across thermistor (Vt) and perform offset cancellation(CDS) Calculate thermistor resistance from Vref and Vt Calculate temperature from the thermistor resistance END The flowchart involves conversion of thermistor resistance to temperature. This is done using the thermistor calculator component. The component supports both LUT and the Steinhart-Hart equation, and provides an API for converting resistance to temperature. CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 45 Example Projects 5.2.3.3.3 RTD Figure 5-10 shows the RTD temperature calculation flowchart. Figure 5-10. RTD Flowchart Start Set IDAC to source 128 uA current Read voltage across RTD sensor at zero current for CDS Connect IDAC current mux to calibration reference resistor and measure voltage V1 CDS and filter V2 Read voltage across calibration resistor zero current for CDS Measure RTD resistance from V2 and V1 CDS and filter V1 Calculate temperature from the RTD resistance Connect IDAC current mux channel to RTD and measure voltage V2 End 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. CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 46 Example Projects 5.2.3.3.4 Diode Figure 5-11. Diode Flowchart Start Connect IDAC current mux to calibration reference resistor Connect IDAC current mux channel to diode Get zero current offset voltage First measurement? No First measurement? No Yes Set IDAC current to 10 uA Set IDAC current to 100 uA Yes Set IDAC current to 10 uA CDS voltage and filter as Vref1 First measurement? Set IDAC current to 100 uA CDS voltage and filter as Vref1 No Calculate the current ratio Yes Get Vbe at 10 uA Get Vbe at 100 uA Calculate temperature from reference voltages and current ratio End Get voltage difference and filter the difference 5.2.3.3.5 RTD Calibration The RTD provided onboard confirms to IEC-70651 class B standards. A class-B RTD conforms to the following tolerance specifications. Tolerance = 0.30 + 0.005|t| This means replacing one RTD with another of the same part number causes a maximum error of 0.3 °C at 0 °C and 0.8 °C at 100 °C. Calibrating the RTD can help avoid this error. AN70698 describes the calibration details. The calibration steps for the RTD are as follows: 1. Scroll down to the Calibrate RTD (eighth) item in the menu using CapSense buttons. CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 47 Example Projects 2. Proceed through calibration steps using mechanical switch SW2 connected to P6[1] of CY8CKIT030 or SW1 connected to P1[7] of CY8CKIT-001. 3. The LCD displays "Set Temp:". Force the RTD temperature to a known measured value between 0 °C and 100 °C and enter that temperature using the CapSense slider and buttons. Use the CapSense slider for coarse temperature setting and the CapSense button for fine settings (P5_5/P0_5 to increment the temperature in 0.1 °C steps and P5_6/P0_6 to decrement the temperature in 0.1 °C). After the temperature is entered accurately, press the mechanical button SW2 (CY8CKIT-030) or SW1 (CY8CKIT-001) to calibrate. 4. The RTD calibration constant is calculated from the measured RTD resistance at the set temperature and the expected temperature value entered by the user. After calibration, the LCD displays the message "Calibrated". Press SW2 (CY8CKIT-030) or SW1(CY8CKIT-001) to go to the main menu temperature display. Figure 5-12. RTD Calibration Enter RTD Cal Enter calibration temperature using CapSense button and slider Set calibration temperature Calculate expected resistance (rCalc) at the given temperature Measure RTD resistance (rMeasured) at calibration temp1 RTD Cal constant = z rCalc/rMeasured Save the RTD calibration constants in EEPROM Go back to the main menu on next switch press Note: The calibration constant is used inside 'RTDRestoTemp' for calibration. On system reset, the calibration constant is initialized as ‘1’. After calibration, the constant is stored in EEPROM. This value can be used for power-on-reset calibration. This can be implemented by users and is not demonstrated in this project. CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 48 Example Projects 5.2.3.3.6 Diode Calibration Diode temperature measurement follows the equation:    V 1 – V 2 q T = ------  ------------------- k   I 1   ln  --I 2  Equation 9 Here  is the ideality factor of the diode, varied from diode to diode. The temperature variation resulting from the ideality factor variation can be calibrated out. As equation 9 shows, variation in  results in a scale error. Performing a scale correction eliminates this error. The procedure to perform scale calibration is as follows: 1. Scroll down to the Calibrate Diode1 (ninth) or Calibrate Diode2 (tenth) item in the menu using CapSense buttons. Proceed through the calibration steps using mechanical switch SW2 connected to P6[1] of CY8CKIT-030 or SW1 connected to P1[7] of CY8CKIT-001. 2. The LCD displays “Set Temp:". Force the diode1 temperature to a known measured value between 0 °C and 100 °C, and enter that temperature using the CapSense slider and buttons. Use the CapSense slider for coarse temperature setting and the CapSense button for fine settings (P5_5/P0_5 to increment the temperature in 0.1 °C steps and P5_6/P0_6 to decrement the temperature in 0.1 °C). After the temperature is entered accurately, press the switch SW2 in CY8CKIT-030 or SW1 in CY8CKIT-001 to calibrate. 3. The diode calibration constant is calculated from the measured temperature and the expected temperature value entered by the user. After calibration, the LCD displays the message "Calibrated". Press SW2 (CY8CKIT-030) or SW1 (CY8CKIT-001) to go to the main menu temperature display. Figure 5-13. Diode Calibration Start Enter the calibration temperature using CapSense button and slider Set calibration temperature (tIdeal) Measure diode temperature tMeasured) Diode Cal constant = tIdeal/tMeasured Save the diode calibration constants in EEPROM Go back to the main menu on next switch press CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 49 Example Projects Note: The calibration constant is used inside diode temperature measurement function for calibration. On system reset, the calibration constant is initialized as ‘1’. After calibration, the constants are stored in EEPROM. These values can be used for power-on-reset calibration. This can be implemented by users and is not demonstrated in this project. 5.2.3.3.7 IC Calibration DS600 IC is used for cold junction compensation. Ideally an isothermal connection should be provided between the cold junction sensor and cold junction terminals. If that is not possible, having the cold junction sensor very close to the cold junction terminals is sufficient as it is done on CY8CKIT025. This may result in a small temperature offset of around 0.5 °C. For high accuracy, a calibration routine, which performs a single point calibration, is provided to calibrate the temperature offset between the cold junction and the IC thermal pads. The calibration steps for the IC temperature measurement are as follows: 1. Scroll down to the Calibrate IC (eleventh) item in the menu using CapSense buttons. 2. Proceed through the calibration steps using mechanical switch SW2 connected to P6[1] of CY8CKIT-030 or SW1 connected to P1[7] of CY8CKIT-001. 3. The LCD displays "Set Temp:". Force the IC temperature to a known measured value between 0 °C and 100 °C and enter that temperature using the CapSense slider and buttons. Use the CapSense slider for coarse temperature setting and the CapSense button for fine settings (P5_5/P0_5 to increment the temperature in 0.1 °C steps and P5_6/P0_6 to decrement the temperature in 0.1 °C). After the temperature is entered accurately, press the mechanical button SW2 (CY8CKIT-030) or SW1 (CY8CKIT-001) to calibrate. 4. The IC calibration constant (Offset) is calculated as the difference in measured temperature and the expected temperature value entered by the user. After calibration, the LCD displays the message "Calibrated". Press SW2 (CY8CKIT-030) or SW1(CY8CKIT-001) to go back to main menu. Figure 5-14. IC Calibration Enter IC Cal Enter calibration temperature using CapSense button and slider Set calibration temperature (tCal) Measure IC temperature (tMeas) IC offset = tMeas - tCal Save the calibration constant in EEPROM Go back to the main menu on next switch press CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 50 Example Projects Note: The calibration constant is subtracted from the measured IC temperature inside 'MeasureColdJnSensorTemp' function, for offset calibration. On system reset, the calibration constant is initialized to ‘0’ and is set to the appropriate value after calibration. The calibration constant stored in EEPROM can be used for power-on-reset calibration. This can be implemented by users and is not demonstrated in this project. 5.2.3.3.8 Noise Reduction and Offset Cancellation The accuracy of temperature reading displayed by a sensor depends on the ADC offset. Reducing ADC offset increases the temperature accuracy. Similarly, electronic noise affects the resolution measurement. A lower noise improves resolution. The techniques used in this example project to reduce offset and noise for all sensors are described in the following sections. Sensor Output Filter A software IIR filter is applied on the output voltage of the thermocouple, RTD, and diode sensors to eliminate noise. See application note, AN2099 - PSoC 1, PSoC 3, and PSoC 5LP - Single-Pole Infinite Impulse Response (IIR) Filters, for details. The filter (attenuation factor) applied depends on the noise on the output voltage of the sensor. The filter for a sensor is selected in such a way that the temperature resolution of the sensor is 0.1 °C. The function FilterSignal() in the code performs filtering. Applying a filter increases the temperature settling time. A filter with a low cut-off frequency takes a much larger time for the temperature to settle down. To avoid large settling times when the temperature changes drastically, an algorithm is used where the filter is applied only when required (when the temperature is closer to the final temperature). The filter attenuation factor can be changed in the filter.h file. For instance, to change the filter attenuation factor of the thermocouple from 4 to 5, go to filter.h and modify the following line of code. /* Filter coefficient for sensors */ #define TC_FILTER_COEFF_SHIFT 4 Note: A higher attenuation factor reduces LCD flicker, but increases the temperature settling time. Correlated Double Sampling (CDS) Correlated double sampling is a technique where the offset and low frequency noise is eliminated by subtracting a zero voltage reading from every voltage sample. See application note AN66444 for more details on correlated double sampling. The ADC multiplexer, Channel 7, is used to make zerovoltage measurements for the thermistor and the thermocouple. To make zero-voltage measurements for the RTD and the diodes, pass a zero current through the RTD, diode, or calibration resistor and measure the ADC output across the RTD/diode/calibration resistor. CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 51 Example Projects 5.3 Sequenced ADC This project demonstrates PSoC's ability to sense multiple inputs such as temperature sensor inputs, power rails, and generic analog inputs at a specific sample rate where the 50- or 60-Hz noise is eliminated. 5.3.1 Project Description This project uses the RTD, IC temperature sensor, and diode temperature sensor from the CY8CKIT-025 DVK. This example also measures a 20 mV full scale input, 100 mV full scale input, 3.3 V rail, and 5 V rail. The 20 mV and 100 mV measurements require external stimulus. You can uses a low noise voltage source or analog output sensors such as a pressure sensor or a load cell to provide 0–20 mV and 0–100 mV inputs. The 5 V and 3.3 V signals can be derived from CY8CKIT030 or CY8CKIT-001. The project user interface is controlled by the CapSense buttons and character LCD. When the example project is programmed on CY8CKIT-030, the LCD displays the measurement from the RTD. Pressing CapSense button P5_5 successively displays measurements from the subsequent temperature sensors and voltage inputs. These measurements are in the following order: diode temperature, IC temperature, 3.3 V rail, 5 V rail, 20 mV full scale input, and 100 mV full scale input. P5_6 can be used to cycle through the measurements in reverse order. In the previous example, readings are only taken when the LCD displays that particular measurement. However, in this project, ADC readings are taken continuously at repeated intervals. This allows filtering of ADC readings to remove specific frequencies of interest, such as 50- or 60-Hz hum. Furthermore, this project configures the delta-sigma ADC for 16-bit resolution instead of the maximum 20-bit resolution. This allows faster ADC conversion times and measurement update rates. 5.3.2 Project Operation 5.3.2.1 Hardware Connections The kit includes example projects for the CY8CKIT-001 DVK, CY8CKIT-030 DVK, and CY8CKIT-050 DVK hardware platforms. The pin mapping for CY8CKIT-030 and CY8CKIT-050 are identical; follow the instructions provided for CY8CKIT-030 PSoC 3 DVK for CY8CKIT-050 PSoC 5LP DVK as well. The main difference between the examples for the CY8CKIT-001 and CY8CKIT-030 platforms is the PSoC pin mapping. The project provided for the CY8CKIT-001 PSoC DVK can be used with both PSoC 3 and PSoC 5LP. See Migrating Projects to use with CY8CKIT-050 and CY8CKIT-010 on page 31 for more details. CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 52 Example Projects 5.3.2.1.1 CY8CKIT-030 PSoC DVK 1. Plug the PSoC Precision Analog Temperature Sensor EBK to port E of the CY8CKIT-030 DVK. 2. Connect 3.3 V on port D to P5_0 on port D 3. The variable resistor (VR) is used for the 5 V input. Turning VR changes the voltage input to PSoC from 0 to VDDA. On the CY8CKIT-030, the VR is directly tied to P6_5. Ensure that the VR is turned to output 5 V. The VR is used to make sure that 5 V is not accidentally driven on the pin if the system is set for 3.3 V. 4. Connect a 20 mV full scale differential signal from a voltage to source P5_2 (+) and P5_3 (–). You can also use an analog output pressure sensor or load cell to give 0-20 mV input. 5. Connect a 100 mV full scale differential signal from a voltage to source P1_6 (+) and P1_7 (–). You can also use an analog output pressure sensor or load cell to give 0-100 mV input. 6. Ensure that the LCD included with the CY8CKIT-030 DVK is attached to the LCD header. Note: For testing purpose an external voltage source can be created by using 1.5 V AA battery and resistor divider. Upper arm of the resistor divider can be 15 K resistor while bottom arm can be 1 K potentiometer. CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 53 Example Projects 7. Set VDDD and VDDA to 5 V using J10 and J11. 8. In the CY8KIT-025 EBK, choose appropriate jumper settings for internal sensors; see the Kit Operation chapter on page 18. 5.3.2.1.2 CY8CKIT-001 PSoC DVK 1. Plug the PSoC Precision Analog Temperature Sensor EBK to port A of the CY8CKIT-001 DVK. 2. In the pin header/breadboard area of the CY8CKIT-001 base board, use jumper wires to make the following connections: a. VR to P0_7. The VR is used as the 5 V input. Ensure that the VR is turned to output 5 V. The VR makes sure that 5 V is not accidentally driven on the pin if the system is set for 3.3 V. b. 3.3 V to P1_2 CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 54 Example Projects 3. Connect a 20 mV full scale differential signal to P0_0 (+) and P0_1 (–). 4. Connect a 100 mV full scale differential signal to P1_6 (+) and P1_7 (–). 5. Set the system to run at 5 V using SW 3; set J7 VDD DIG and J6 VDD ANLG to VDD = 5 V. 6. Ensure that the LCD included with the CY8CKIT-001 PSoC DVK is attached and the LCD power jumper (J12) is in the ON position. 7. In the CY8CKIT-025 EBK, choose appropriate jumper settings for internal sensors; see the Kit Operation chapter on page 18. 5.3.2.2 Run Sequenced ADC Example Firmware 5.3.2.2.1 CY8CKIT-030 PSoC 3 DVK The steps to run the example firmware on CY8CKIT-030 are: 1. Attach a USB cable from the PC to the PSoC 3 DVK program/debug USB port (use J1, the USB connector closest to the corner of the board). 2. Open the SequencedADC_030_050 project using PSoC Creator and select Debug > Program to program the PSoC. 3. Detach the USB cable and connect hardware according to Hardware Connections on page 52. 4. Plug at 12 V wall-wart into the J4 barrel jack connector. 5. Press the Reset (SW1) button on the PSoC 3 DVK to run the newly programmed firmware image. 6. On reset, the LCD displays the RTD temperature, which is the first item in the user selectable menu. 7. Press CapSense button P5_5 to scroll up the menu and P5_6 to scroll down the menu. CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 55 Example Projects Note: In the firmware, voltage displayed on the LCD for the 5-V rail is truncated to two digits after the decimal point. Therefore, when the potentiometer is turned to the 0V position, if the ADC result is negative due to negative offset error, you will see ‘–0.00’ on the LCD. Increase the number of digits after the decimal point to be displayed on the LCD by increasing the floating point qualifier in the line number 105 of the display.c file. 5.3.2.2.2 CY8CKIT-001 PSoC DVK The steps to run the example firmware on CY8CKIT-001 are: 1. Apply 12 VDC power to the PSoC DVK. 2. Attach the MiniProg3 device, first to a USB port on the PC and then to the PROG port on the CY8CKIT-009 PSoC 3/CY8CKIT-010 PSoC 5LP processor module. 3. Open the SequenceADC_001 project using PSoC Creator and select Debug > Program to program the PSoC. 4. Disconnect power to the PSoC DVK and connect hardware according to Hardware Connections on page 33. 5. Power the PSoC DVK. 6. On reset, the LCD displays a welcome message and then the RTD temperature, which is the first item in the user selectable menu. 7. Press CapSense button P0_5 to scroll up the menu and P0_6 to scroll down the menu. Note: The diode temperature in CY8CKIT-001 is slightly lower than the actual temperature. This is because CY8CKIT-001 is a general-purpose board and is not optimized for analog routing. 5.3.2.3 Testing the Project For best results when testing the temperature measurements, ensure that you have good thermal contact between the sensor (RTD, diode, or IC sensor) and your reference thermometer. 5.3.2.4 Expected Performance and Test Results This section provides details about the expected performance of the temperature, voltage, and power rail measurements. The output expected from the temperature sensors are similar to those described in the previous example project, except for minor differences, such as use of 16-bit ADC for all measurements. It is recommended to see Expected Performance and Test Results on page 36 before reading this section. The focus of this example is to show multiplexing multiple input sources, that is, voltages, temperatures, and power rails. The section Expected Performance and Test Results on page 36 details the tolerance specification of each temperature sensor and the expected temperature performance from the sensors. Following are typical expected results for each measurement observed on a sample board. 5.3.2.4.1 Voltage (20 mV) Input A voltage source is used to provide inputs from –20 mV to +20 mV and the output displayed by PSoC is compared to a multimeter output. The 20 mV reading should typically be within ± 40 µV of the actual value. The ADC gain error is the main factor driving this error and the PSoC 3 ADC with a maximum gain error of 0.2% keeps the measurement inaccuracy to < 40 µV. 5.3.2.4.2 100 mV Input A voltage source is used to provide inputs from –100 mV to +100 mV and the output displayed by PSoC is compared to a multimeter output. CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 56 Example Projects The 10 mV reading should typically be within ± 200 µV of the actual value. The ADC gain error is the main factor driving this error and PSoC 3 ADC with a maximum gain error of 0.2 percent keeps the measurement inaccuracy to = # of Slots? Y Current Slot = 0 ADC Reconfiguration Process N Save Invalid Flag from last reading Next ADC Config Different? Does Current Slot = HW Counter N Reset HW Counter Set Invalid Flag Y N Set Next Invalid Flag Y Stop ADC Reconfigure It Restart ADC Clear next Invalid Increment Next Slot Next Slot >= # of Slots? Clear Next Invalid Flag Y ADC Config Valid? Get ADC Reading Result N Does Current Slot = HW Counter Y N Set Next Invalid Flag Next Slot = 0 Y N Configure IDAC Range, Value and Mux for Next Slot Configure ADCMux for Next Slot Filter Readings See AN2099 for Detail Store ADC reading and status in Ping Pong Buffer ADC Reconfiguration Process The SlotCounter is used to count ADC EOCs. This hardware counter is compared with the current slot value in the ADC ISR. If they do not match, then the measurement is flagged as invalid. This is CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 65 Example Projects done after the ADC reconfiguration to ensure that reconfiguration completed before the next ADC SOC is triggered. 5.3.3.3.2 Fixed Point Math This project does not use floating point math when calculating the measurement results. This is done to reduce processor overhead when converting ADC readings into measurement values. Therefore, scaling is used to calculate the final measurement value. For ease of use, the values are converted to float when displayed on the LCD. The following sections describe each measurement and how its readings are converted into measurement values. 20 mV and 100 mV Input For 20 mV and 100 mV reading, ADC_COUNTS_PER_VOLT is used to convert the ADC counts to volts. Because integer math is used, dividing the ADC counts by this constant results in a precision of only 1 V, which is not adequate to measure a 20 mV or 100 mV full scale input. To fix this, the ADC counts for these readings are scaled up by 10000 and divided by ADC_COUNTS_PER_VOLT. The result is in ten-thousandths of a volt. 3.3 V Rail and 5 V Rail For the 3.3 V and 5 V reading, ADC_COUNTS_PER_VOLT is used to convert the ADC counts to volts. Because integer math is used, dividing the ADC counts by this constant results in a precision of only 1 V, which is not adequate to measure a 3.3 V or 5 V rail. To fix this, the ADC counts for these readings are scaled up by 1000 and then divided by ADC_COUNTS_PER_VOLT. The result is in thousandths of a volt. RTD and DS600 To avoid floating point math, the conversion from ADC readings to temperature uses integer math. To preserve precision, the readings are scaled up. Thus the final result of the temperature measurements is in hundredths of a degree C. For more information on the conversion, see the inline code comments in the associated project. Diode The diode temperature measurement uses floating point math. This is because the natural log of the current ratio is taken. Not using floating point math with this measurement results in poor accuracy and stability of the diode measurement. 5.3.3.3.3 Filter A software IIR filter is applied on all ADC readings to eliminate noise. See application note AN2099 for details on the software IIR filter. The filter (attenuation factor) applied depends on the noise on the voltage output of the sensor. Applying a filter increases the measurement settling time. A very low cut-off filter requires a much larger time for the measurement to settle down. To avoid large settling times when the input changes drastically, an algorithm is used where the filter is applied only when required (when the measurement is closer to the final measurement). The filter attenuation factor can be changed in the Init_Buffers routine in Readings.c. For example, to change the filter attenuation factor of 3.3 V from 8 to 16, go to Readings.c and modify the following line of code. Filter_CoeffBuf[READ_RAIL3V3]=8; to Filter_CoeffBuf[READ_RAIL3V3]=16; Note that a higher attenuation factor reduces LCD flicker, but increases temperature settling time. CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 66 Example Projects 5.3.3.3.4 Correlated Double Sampling (CDS) Correlated double sampling is a technique where the offset and low frequency noise is eliminated by subtracting a zero voltage reading from every voltage sample. See application notes AN2226 and AN66444 for more details on correlated double sampling. The ADCMux, Channel 8, is used to make zero-voltage measurement for the DS600. To make zero-voltage measurement for the RTD and diode, pass a zero current through the RTD, diode, or calibration resistor and measure the ADC output across the RTD/diode/calibration resistor. 5.3.3.3.5 Calibration For this project, user calibration is not available for the temperature sensors. The 3.3 V and 5 V measurements are adjusted by a calibration factor. This is because the ADC configuration (±6.144 V ADC input range) used to read the 3.3 V and 5 V rail is not factory calibrated. To achieve this calibration factor, a voltage is read with one of the factory calibrated ADC ranges (ADC configuration 1 – ±1.024 V range); that same value is read with the non-factory calibrated range. The ratio of these two readings is then used to adjust the 3.3 V and 5 V measurements. This calibration is done before the main code loop. CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 67 Example Projects 5.4 Thermal Management This project demonstrates fan speed control using analog temperature sensors. 5.4.1 Project Description The thermal management project controls the fan speed based on the temperatures measured by the temperature sensors. This project uses the CY8CKIT-036 Thermal Management (TME) EBK in addition to the CY8CKIT-025 EBK. The example project controls two fans based on their zone temperatures. The concept of a thermal zone and the sensors used in a specific zone are explained in Project Details on page 75. On reset, the LCD displays Zone 1 Summary. Press switch SW2 to cycle through the three menu items: ■ Zone 1 Summary: Temperature algorithm used to compute zone temperature, desired fan speed, and actual fan speed ■ Zone 2 Summary: Temperature algorithm used to compute zone temperature, desired fan speed, and actual fan speed ■ Temperature Sensor Summary: The temperatures of the individual temperature sensors in each zone and the zone temperatures Figure 5-21. Thermal Management EBK 5.4.1.1 Thermal Management EBK Description The Thermal Management (TME) EBK contains two four-wire, 12 V brushless DC fans with connectors to support an additional two fans for designers who need to prototype with their own specific fan models. Six temperature sensors (four different kinds) are also installed on the kit: ■ TMP175 I2C digital temperature sensor ■ Two TMP05 PWM output digital temperature sensors ■ DS18S20 "One Wire" digital temperature sensor ■ Two MMBT3094 temperature diodes. CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 68 Example Projects This combination of hardware elements enables designers to rapidly prototype thermal management solutions in a variety of configurations. The TME EBK also provides an I2C/SMBus/PMBus compatible header to support systems that require communication with a host controller. This functionality is implemented in a single PSoC 3. The TME EBK routes the input/output signals for thermal management to a PSoC 3 mounted on a development kit platform such as the CY8CKIT-001 or CY8CKIT-030. PSoC 3 is not mounted on the TME EBK. The CY8CKIT-036 TME EBK has three example projects that demonstrate firmware-based fan control, hardware-based closed-loop fan control, and a thermal management system. A detailed explanation of the TME EBK and the firmware examples that are provided with the kit are available at www.cypress.com/go/CY8CKIT-036. 5.4.1.2 Using TME EBK with CY8CKIT-025 You can control the fans in the TME EBK using the temperature sensors in the CY8CKIT-025 EBK. The TME EBK has only one analog temperature sensor, which is the diode-based temperature sensor. To illustrate the analog temperature sensing capabilities of PSoC 3 better, the CY8CKIT-025 EBK is combined with the TME EBK to demonstrate thermal management using different analog temperature sensors such as diode and RTD. Figure 5-22 shows the CY8CKIT-036 TME EBK and CY8CKIT-025 EBK connected to the CY8CKIT030 PSoC 3 DVK. The CY8CKIT-025 EBK is connected to port E and the CY8CKIT-036 TME EBK is connected to port D. The same setup and connections can be used when using CY8CKIT-050. Figure 5-23 shows the CY8CKIT-036 TME EBK and CY8CKIT-025 EBK connected to the CY8CKIT001 PSoC DVK. The CY8CKIT-025 EBK is connected to port A and the CY8CKIT-036 TME EBK is connected to port B. The same setup and connections can be used when using CY8CKIT-010. Figure 5-22. TME EBK and CY8CKIT-025 EBK Connected to CY8CKIT-030 PSoC 3 DVK CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 69 Example Projects Figure 5-23. TME EBK and CY8CKIT-025 EBK Connected to CY8CKIT-001 PSoC 1 DVK 5.4.2 Project Operation 5.4.2.1 Hardware Connections The CY8CKIT-025 kit includes example projects for the CY8CKIT-001 DVK, CY8CKIT-030 DVK, and CY8CKIT-050 DVK hardware platforms. The pin mapping for CY8CKIT-030 and CY8CKIT-050 are identical; follow the instructions provided for CY8CKIT-030 PSoC 3 DVK for CY8CKIT-050 PSoC 5LP DVK as well except that PSoC 5LP device CY8C5868AXI-LP035 should be selected (Project > Device selector). The main difference between the examples for the CY8CKIT-001 and CY8CKIT-030 platforms is the PSoC pin mapping. 5.4.2.1.1 CY8CKIT-030 PSoC 3 DVK 1. No jumper wires are required for the PSoC 3 DVK examples because the buttons and potentiometer are hardwired to GPIOs. Ensure that the LCD included with the PSoC 3 DVK is attached. 2. Set VDDD and VDDA to 3.3 V using J10 and J11. CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 70 Example Projects Figure 5-24. CY8CKIT-030 PSoC 3 DVK Power Jumpers 3. Ensure that POT_PWR is enabled by installing a jumper on J30. Figure 5-25. CY8CKIT-030 PSoC 3 DVK Potentiometer Power CAUTION: The TME EBK plugged into port D of the CY8CKIT-030 DVK uses the SWD/JTAG programming pins for fan control as well. Due to this pin sharing, the TME EBK should not be attached to the CY8CKIT-030 DVK while programming the PSoC 3 device using MiniProg3 or DVKProg3 programmer. After the programming is complete, remove the programmer from the programming header on the PSoC 3 DVK and then attach the TME EBK to port D. Due to pin sharing, debugging the project is also not possible because it uses the same programming pins. 5.4.2.1.2 CY8CKIT-001 PSoC DVK 1. In the pin header/breadboard area of the PSoC DVK base board, use jumper wires to make the following connections: ❐ VR to P1_2 ❐ SW1 to P2_7 Figure 5-26. CY8CKIT-001 PSoC DVK Breadboard CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 71 Example Projects 2. Set the system to run at 3.3 V using SW3 and set J6 VDD DIG and J7 VDD ANLG to VDD = 3.3 V. Figure 5-27. CY8CKIT-001 PSoC DVK Power Jumpers 3. Ensure that the LCD included with the PSoC DVK is attached and that the LCD power jumper (J12) is in the ON position. Figure 5-28. CY8CKIT-001 PSoC DVK LCD Power Jumper 4. Ensure that the VR_PWR jumper (J11) is installed. Figure 5-29. CY8CKIT-001 PSoC DVK VR_POWER Jumper CAUTION: The TME EBK plugged into port B of the CY8CKIT-001 DVK uses the SWD/JTAG programming pins for fan control as well. Due to this pin sharing, the TME EBK should not be attached to the PSoC DVK while programming the PSoC 3 device on the DVK using MiniProg3 programmer. After the programming is complete, remove MiniProg3 from the programming header on the PSoC DVK and then attach the TME EBK to port B. Due to pin sharing, debugging the project is also not possible because it uses the same programming pins. CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 72 Example Projects 5.4.2.1.3 CY8CKIT-025 PSoC Precision Analog Temperature Sensor EBK 1. Make sure the RTD jumper J6 is on; on jumpers J8 and J9, short 1-2 with wires so that the onboard RTD is used for temperature measurements. Figure 5-30. CY8CKIT-025 RTD Jumper 2. Connect the diodes, as shown in Figure 5-31. Figure 5-31. CY8CKIT-025 Diodes 5.4.2.1.4 CY8CKIT-036 Thermal Management EBK 1. Connect the fans to headers fan 3 and fan 4, as shown in Figure 5-32. Note that the fans are connected to headers 1 and 2 by default. Figure 5-32. Thermal Management EBK Fans 2. Configure jumper J9 to power the thermal management EBK using an external power supply, as shown in Figure 5-33. CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 73 Example Projects Figure 5-33. External Power Supply Connected 5.4.2.2 Run Thermal Management System Firmware 5.4.2.2.1 CY8CKIT-030 PSoC 3 DVK The steps to run the example firmware on CY8CKIT-030 are: 1. Make the hardware connections on the CY8CKIT-030 DVK, as explained in 5.4.2.1.1 CY8CKIT030 PSoC 3 DVK. 2. Attach a USB cable from the PC to the PSoC 3 DVK program/debug USB port (use J1, the USB connector closest to the corner of the board). Ensure that the TME EBK is not attached to the PSoC 3 DVK before attaching the USB cable for programming. 3. Open the ThermalManagementSystem_030_050 project using PSoC Creator and select Debug > Program to program the PSoC. 4. Detach the USB cable; if the DVK is powered by external power supply, disconnect power supply to the DVK as well. 5. Connect the CY8CKIT-025 EBK and TME EBK to the DVK, as shown in Figure 5-22. 6. Power the PSoC 3 DVK and the TME EBK, as shown in Figure 5-22. 7. Press the Reset (SW1) button on the PSoC 3 DVK to run the newly programmed firmware image. 8. On reset, the LCD displays a welcome message and starts with the Zone 1 temperature reading and the corresponding temperature calculation algorithm. The desired and actual fan speeds corresponding to that zone are also displayed. 9. Use the push button SW2 to view the different zone characteristics. 5.4.2.2.2 CY8CKIT-001 PSoC DVK The steps to run the example firmware on CY8CKIT-001 are: 1. Make the hardware connections on the CY8CKIT-001 DVK, as explained in 5.4.2.1.2 CY8CKIT001 PSoC DVK. 2. Apply 12 VDC power to the PSoC DVK. 3. Attach the MiniProg3 device, first to a USB port on the PC and then to the PROG port on the CY8CKIT-009 PSoC 3/CY8CKIT-010 PSoC 5LP processor module. Ensure that the TME EBK is not attached to the PSoC 3 DVK before attaching the USB cable for programming. CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 74 Example Projects 4. Open the ThermalManagementSystem_001 project using PSoC Creator and select Debug > Program to program PSoC 3. 5. Detach the MiniProg3 and remove power supply to the PSoC DVK. 6. Connect the CY8CKIT-025 EBK and TME EBK to the PSoC DVK, as shown in Figure 5-23. 7. Power the PSoC DVK and TME EBK, as shown in Figure 5-23. 8. Press the Reset (SW4) button on the PSoC 3 DVK to run the newly programmed firmware image. 9. On reset, the LCD displays a welcome message and starts with the Zone 1 temperature reading and the corresponding temperature calculation algorithm. The desired and actual fan speeds corresponding to that zone are also displayed. 10.Use the push button SW1 to view the different zone characteristics. 5.4.2.3 Testing the Project In this project, the fan temperature is controlled based on the temperature of the corresponding thermal zone. To test the closed loop speed control of Fan 3, vary the potentiometer on the DVK. This simulates the condition of changing the corresponding zone temperature in the project. The speed of Fan 3 is adjusted according to the temperature vs speed graph shown in Figure 5-34. To test the closed loop speed control of Fan 4, touch the RTD sensor on the CY8CKIT-025 EBK. This results in variations in the measured RTD temperature. The speed of Fan 4 is adjusted according to the temperature vs speed graph shown in Figure 5-35. On reset, the LCD displays the characteristics of Zone 1. These characteristics include the zone temperature, temperature calculation algorithm, desired fan speed, and the actual fan speed. The fan speeds will match the corresponding zone thermal profiles. Press the push button (SW1 on CY8CKIT-001 or SW2 on CY8CKIT-030) once to view the characteristics of Zone 2. Press the push button (SW1 on CY8CKIT-001 or SW2 on CY8CKIT-030) again to view the individual sensor temperatures for each zone and the weighted composite zone temperature. Pressing the button again will repeat this display sequence. 5.4.3 Project Details This project demonstrates how the temperature sensors in the CY8CKIT-025 EBK combined with the fans on the TME EBK can create a complete thermal management system. The example shows how to combine temperature readings from a number of temperature sensors in a variety of ways and use the composite temperature to set desired fan speeds according to a customizable transfer function. The thermal management example uses the concept of a "Thermal Zone", which describes how to : ■ combine multiple temperature sensor readings to form a composite zone temperature ■ map the zone temperature to a fan speed By this definition, each fan is controlled according to its own independent thermal zone. This example has two thermal zones because the TME EBK has only two fans installed. Algorithms currently implemented to combine multiple temperature sensors into a composite zone temperature include: straight average, weighted average, and maximum. In this example, the weighted method is used on both fans. A zone temperature-to-fan speed transfer function is then definable for each zone. Linear and table driven transfer functions are currently implemented. This example uses the table driven transfer function on both fans; that is, a look-up table maps the composite zone temperature-to-fan speed. This example is a simulation of a thermal management system. Zone 1, corresponding to Fan 3 in Figure 5-34 combines temperature measurements from two temperature sensors (potentiometer CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 75 Example Projects temperature emulator and RTD). The potentiometer temperature emulator allows easy demonstration of fan control over a wide simulated temperature range without the need for an environmental chamber to cycle through temperatures. In Zone 1, the temperature sensors are combined using a weighted average where the potentiometer is given 90 percent weight and the RTD is given 10 percent weight. Adjust the potentiometer (R20 on the CY8CKIT-001 DVK and R56 on the CY8CKIT-030 DVK) to vary the simulated temperature value in the approximate range of 15 °C to 100 °C. The Zone 1 speed transfer function is table driven and follows the profile shown in Figure 5-34. Figure 5-34. Thermal Management System Project - Zone1 Thermal Profile Zone 2, corresponding to Fan 4 in Figure 5-35, consists of two temperature sensors and a single fan. The Zone 2 speed transfer function is table driven and is shown in Figure 5-35. Note that the temperature range is very narrow and close to room temperature. This is to allow simple testing at room by touching a temperature sensor with a warm finger to cause a fan speed change. In Zone 2, the temperature sensors are combined using a weighted average where the RTD is given 90 percent of the weight and the diode is given 10 percent weight. In this example, the RTD temperature reading dominates the overall zone temperature calculation. Figure 5-35. Thermal Management System Project - Zone2 Thermal Profile CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 76 Example Projects 5.4.3.1 Project Schematic Figure 5-36 shows the PSoC Creator schematic of the project. Figure 5-36. PSoC Creator Schematic A four-channel ADC is used to measure the voltages across the RTD, diode, RTD/diode current calibration resistor, and potentiometer, which simulates an analog temperature sensor. IDAC is used to provide the excitation currents for the diode, RTD, and calibration resistor. The closed loop fan controller component senses and controls the fan speed. Application notes AN60590 and AN70698 provide detailed explanations on temperature measurement using diode and RTD, respectively. Application note AN66627 describes the fan controller operation in detail. 5.4.3.2 Component Configuration Figure 5-37 and Figure 5-38 show the FanController component configuration. CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 77 Example Projects Figure 5-37. FanController Component Configuration - Basic Tab The Fan Control Method is chosen as hardware (UDB), which means that the fan speed is controlled using the hardware blocks inside PSoC without any CPU intervention. See the FanController component datasheet in PSoC Creator for details on the other parameters. Figure 5-38. FanController Component Configuration - Fans Tab This tab provides the option to choose the number of fans and the speed to RPM mapping of each fan. The individual fan parameters are configured, as shown in Figure 5-38. The configuration is done based on the datasheet specifications of the fans used on the TME EBK. CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 78 Example Projects Figure 5-39 shows the ADC configuration to measure the potentiometer voltage. The ±6.144 V voltage range is chosen because the potentiometer voltage can vary from 0 to VDDA. The Bypass Buffer option is selected for the Buffer Mode parameter to measure voltage near the supply rails. Figure 5-39. ADC Configuration for Potentiometer Voltage Measurement Figure 5-40 shows the ADC configuration to measure voltage across the sensors (diode and RTD). The Resolution parameter is set to 20 bits to perform high-resolution temperature measurements. Figure 5-40. ADC Configuration for Temperature Sensor Measurement CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 79 Example Projects Figure 5-41 shows the IDAC component configuration. The Polarity parameter of the IDAC is set to the current sourcing mode and the Speed parameter is set to High Speed to have a faster settling time for the IDAC output. Figure 5-41. IDAC Configuration 5.4.3.3 Firmware Description and Flowchart The thermal management system example consists of the main application and thermal manager. The main application is responsible for the user interface and for periodically calling the thermal manager. The application implementation is available in main.c and on the Test Application tab of the project schematic. The thermal manager implementation is available in ThermalManager.c and on the Thermal Manager tab of the project schematic. The main application must call ThermalManager_Start() to initialize the thermal manager. Then it must periodically call ServiceThermalManager() to run temperature and speed updates. In this example, this is done every 500 ms but can be changed by modifying #define THERMAL_UPDATE_MS_RATE in main.c. All the parameters that define the zone composite temperature sensor algorithm and the zone temperature-to-fan speed algorithm are defined in the beginning of ThermalManager.c. To modify these settings, refer to ThermalManager.h for the relevant keywords. The following flowchart shows the basic function of the thermal manager along with the APIs in ThermalManager.c that implement the main service loop. CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 80 Example Projects Figure 5-42. Thermal Manager Flowchart Start Initialize Components and Variables 500 ms Timer Expired? N Y Calculate Zone1 and Zone 2 Temperatures Calculate Fan 3 and Fan 4 Speeds based on Thermal Profiles Fan Speed Needs Change? N Y Set Desired Fan Speeds Launch Next Temperature Measurement Handle Button Presses and Update LCD In this example, the LCD displays status information about thermal management system across three screens. You can cycle through the status screens by pressing SW1 on the CY8CKIT-001 DVK or SW2 on the CY8CKIT-030 DVK. The three screens are: ■ Screen 1 - Zone 1 Summary This screen displays the current status of Zone 1. Line 1 displays the zone number, current composite zone temperature, and the zone temperature calculation algorithm used. Line 2 displays the desired fan speed and the actual fan speed for Zone 1. Figure 5-43. Zone 1 Summary Z 1 : T = 1 6 F 3 : 4 5 0 0 ■ WE I GH T E D A 3 : 4 5 1 5 Screen 2 - Zone 2 Summary This screen displays the current status of Zone 2. Line 1 displays the zone number, current composite zone temperature, and the zone temperature calculation algorithm used. Line 2 displays the desired fan speed and the actual fan speed for Zone 2. CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 81 Example Projects Figure 5-44. Zone 2 Summary Z 2 : T = 2 6 F 4 : 7 0 0 0 ■ WE I GH T E D A 4 : 7 0 6 2 Screen 3 - Temperature Sensors Summary This screen displays the current temperature sensor readings for all sensors in the system. Line 1 displays the Zone 1 temperature sensor values. The temperature on the extreme left is the zone's composite temperature followed by the temperatures of each contributing sensor. Line 2 displays the same information for Zone 2. Figure 5-45. Temperature Sensors Summary Z 1 : T = 7 9 Z 2 : T = 3 1 ( 8 5 , 2 5 ) ( 8 5 , 2 5 ) CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 82 A. Appendix A.1 Schematic J3 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 P3_7 P3_5 P3_3 P3_1 P0_7 P0_5 P0_3 P0_1 VSSA P4_7 P4_5 P4_3 P4_1 P12_2 P12_0 V3_3 Vin 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 2 P3_6 4 P3_4 6 P3_2 8 P3_0 10 RES11 12 P0_6 14 P0_4 16 P0_2 18 P0_0 20 RES10 22 P4_6 24 P4_4 26 P4_2 28 P4_0 30 RES9 32 P12_3 34 P12_1 36 Vadj 38 V5_0 40 1 2 P3_1 P3_6 P4_2 J8 P3_4 TP6 1 P4_0 NO LOAD VSSA TP5 1 1 NO LOAD 1 2 J6 + 1 2 3 4 5 6 7 8 P4_3 P3_7 R8 100E RTD1 PTS080501B100RP100 0.1% P4_5 1% TP4 1 J4 P4_4 1 J9 P4_1 1 2 1 NO LOAD Diode R7 20E 1% R10 20E 20x2_Header VSSA 1% VSSD VSSA Note: P0_2 and P0_3 is for co-related double sampling VSSA Note: CONNECT J6-1 and J6-2 FOR NORMAL OPERATION, DISCONNECT J6-1 and J6-2 FOR EXTERNAL RTD. CONNECT EXTERNAL RTD ACROSS J8 AND J9. From Expansion Connector of PSoC Development Kit and PSoC 3 Development Kit RTD V3_3 R6 330K R4 V3_3 1% 0E V3_3 DS600U+ U1 7 6 5 9 SO8 GND VDD CTG TO SD !TO Vth Vout 1 0402 8 1 2 3 P0_0 P0_5 R5 1.5k TH1 NCP18XH103F03RB 1 2 3 TP1 TP2 J5 TP3 1 2 PCC-SMP-K 1 2 P0_4 1 1 R3 0E 1 1 J2 RTD/Diode Calibration VSSA VSSA + J7 1% 2 1 2 P0_1 3 4 P0_6 Power Supply VSSA R9 10K CP 0.1% 120-09802-0 PDC-09802 VSSA VSSA Thermistor CYPRESS SEMICONDUCTOR © 2011 Title CY8CKIT-025 PSoC Precision Analog Temperature Sensor Expansion Board Kit Thermocouple Note: Place U1 close to Thermocouple Note: Place J5-2 TO J5-3 FOR NORMAL OPERATION, Place J5-2 TO J5-1 FOR EXTERNAL INPUT AT J7 Size A Date: Document Number REF-15102 Friday, April 01, 2011 Rev ** Sheet 1 of CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 1 83 Appendix A.2 Board Layout A.2.1 PDC-09802 Top A.2.2 PDC-09802 Bottom CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 84 Appendix A.3 Item Bill of Materials (BOM) Qty. Reference Value 1 Description Manufacturer Manufacturer Part Number PCB Cypress PDC-09802 Rev02 2 1 J3 40 Pin Header CONN HEADER .100 DUAL R/A 40POS Protectron Electromech P9104-40-12-1 3 1 J2 Thermocople Connector CONN OMEGA Thermocouple Type K OMEGA PCC-SMP-K-5 4 1 TH1 THERMISTOR THERMISTOR 10K OHM NTC 0603 NTC 10K OHM 1% Murata NCP18XH103F03RB 5 1 R9 10K, 0.1% RES 10K OHM 1/8W .1% 0805 SMD Panasonic - ECG 6 1 J4 8 PIN Connector CONN TERM BLOCK T/H 8POS 3.5MM Phoenix Contact 1984675 7 3 J7, J8, J9 2 Pin Jumper Terminal Blocks PT 1.5/2-3.5H 2POS HRZ 3.5mm SCREW Phoenix Contact 1984617 8 2 R7, R10 20E, 1% RES 20.0 OHM 1/8W 1% 0805 SMD Vishay/Dale CRCW080520R0FKEA TEMP SENSOR RTD 100 OHM 0805 Vishay/Beyschlag PTS080501B100RP100 ERA-6AEB103V 9 1 RTD1 TEMP SENSOR RTD 10 1 R8 100E, 0.1% RES 100 OHM 1/8W 0.1% 0805 SMD Panasonic - ECG ERA-6AEB101V 3M 961102-6404-AR 11 1 J6 2p_jumper CONN HEADER VERT SGL 2POS GOLD 12 2 R3, R4 0E Resistor RES 0.0 OHM 1/8W 0805 SMD Panasonic - ECG ERJ-6GEY0R00V IC SENSOR TEMP 8-USOP Maxim Integrated Products DS600U+ 13 1 U1 DS600U+ 14 1 R6 330K, 1% RES 330K OHM 1/8W 1% 0805 SMD Panasonic - ECG ERJ-6ENF3303V 15 1 R5 1.5K, 1% RES 1.50K OHM 1/8W 1% 0805 SMD Panasonic - ECG ERJ-6ENF1501V 16 1 J5 3p_jumper CONN HEADER VERT SGL 3POS GOLD 3M 961103-6404-AR No Load Components 17 1 TP1 RED TP TEST POINT PC MINI .040"D RED Keystone Electronics 5000 18 2 TP2, TP3 BLACK TP TEST POINT PC MINI .040"D RED Keystone Electronics 5001 19 3 TP4, TP5, TP6 PADS PADS Special Jumper Installation Instructions 20 1 J6 Install jumper Rectangular Connectors MINI JUMPER Kobiconn across pins 1 and 2 GF 13.5 CLOSE TYPE BLACK 151-8030-E 21 1 J5 Install jumper Rectangular Connectors MINI JUMPER Kobiconn across pins 3 and 2 GF 13.5 CLOSE TYPE BLACK 151-8030-E Install as per Assembly drawing 22 A.4 3 BUMPER CLEAR .500X.23" SQUARE Richco Plastic Co RBS-3R Regulatory Compliance Information The CY8CKIT-025 PSoC Precision Analog Temperature Sensor Expansion Board has been tested and verified to comply with the following electromagnetic compatibility (EMC) regulations. ■ EN 55022:2010 Class A - Emissions ■ EN 55024:2010 Class A - Immunity CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 85 Revision History Document Revision History Document Title: CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide Document Number: 001-65791 Revision ECN# Issue Date Origin of Change ** 3222188 04/11/11 PFZ *A 3455347 11/29/11 SASH Updated PSoC Creator version. *B 3561312 03/24/12 RKAD Updated existing project; added two new projects. *C 3639690 06/07/12 PFZ Updates to Additional Resources section. Updated images in the Example Projects chapter. *D 3737398 09/07/12 PFZ Document changes to reflect support for PSoC5 Description of Change Initial version of kit guide. Added the Safety section. *E 3954642 03/28/13 VRNK Updated images in the Code Examples chapter. Minor updates throughout the document. *F 3988373 04/26/13 VRNK Updated “CY8CKIT-001 PSoC DVK Thermistor Temperature” on page 40 and “CY8CKIT-030 PSoC DVK” on page 53. *G 4121210 09/12/13 SASH Updated images for PSoC Creator ECR. Added section 5.1.1 *H 4335470 04/07/14 RKAD Updated section 5.2.2.4.5. *I 5406476 08/17/16 SRDS Updated PSoC Creator version to PSoC Creator 3.3 CP3; updated related images. Updated PSoC Programmer version to 3.24.2. Added information about floating point variables in “Migrating Projects to use with CY8CKIT-050 and CY8CKIT-010” on page 31. Updated to new template. *J *K 5446907 5705955 09/23/2016 04/21/2017 SRDS / SAGA RKAD Updated Software Installation chapter on page 15: Updated Figure 2-2. Updated Figure 2-4. Updated to new template. Completing Sunset Review. CY8CKIT-025 PSoC® Precision Analog Temperature Sensor Expansion Board Kit Guide, Doc. # 001-65791 Rev. *K 86