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Preface

©

 2005 Microchip Technology Inc.

DS51594A-page 3

RECOMMENDED READING

This user's guide describes how to use Humidity Sensor PICtail™ Demo Board. Other 
useful documents are listed below  and are recommended as supplemental reference 
resources.

PICkit™ 2 Microcontroller Programmer User’s Guide (DS51553)

Contains instructions on how to use the PICkit 2 Microcontroller Programmer hardware 
and software.

PICkit™ 1 Flash Starter Kit User’s Guide (DS40051)

Contains instructions on how to use the PICkit 1 Flash Starter Kit hardware and 
software.

MPLAB

®

 ICD 2 In-Circuit Debugger User’s Guide (DS51331)

This user’s guide covers Microchip’s low cost, real-time debugger and programmer for 
selected PICmicro

®

 Microcontrollers (MCUs) and dsPIC

®

 Digital Signal Controllers 

(DSCs).

AN1016, “Detecting Small Capacitive Sensors Using the MCP6291 and 
PIC16F690 Devices” (DS01016)

Explains the functionality and design of this board’s circuit. Contains measurement 
results.

MCP6291/2/3/4/5 Data Sheet (DS21812)

Gives detailed information on the MCP6291/2/3/4/5 Op Amps.

PIC16F685/687/689/690 Data Sheet (DS41262)

Gives detailed information on the microcontroller used on the Humidity Sensor PICtail™ 
Demo Board.

PIC16C745/765 Data Sheet (DS41124)

Gives detailed information on the PICmicro microcontroller used on the PICkit 1 Flash 
Starter Kit.

The following document is available on the internet from the company listed, and is 
recommended as a supplemental reference resource.

Humirel, “Relative Humidity Sensor HS1100LF / HS1101LF,” Data Sheet, Rev. C, 
Sept. 2004.

Gives detailed information on Humirel’s (www.humirel.com) HS1101LF capacitive 
relative humidity sensor.

Summary of Contents for Humidity Sensor PICtail

Page 1: ...2005 Microchip Technology Inc DS51594A Humidity Sensor PICtail Demo Board User s Guide...

Page 2: ...e U S A All other trademarks mentioned herein are property of their respective companies 2005 Microchip Technology Incorporated Printed in the U S A All Rights Reserved Printed on recycled paper Note...

Page 3: ...Kit Contents 5 1 3 Humidity Sensor PICtail Demo Board 5 1 4 Associated Tools 7 1 5 Assembly Code Modules 8 Chapter 2 Setup and Installation 2 1 Introduction 9 2 2 Required Tools 9 2 3 Setting up the...

Page 4: ...n 19 A 2 Highlights 19 A 3 Demonstration Board Description 19 A 4 The Reduced Current Modification 20 A 5 Additional Comments 20 Appendix B Bill Of Materials BOM B 1 Humidity Sensor PICtail Demo Board...

Page 5: ...erify the set up Chapter 3 Operation This chapter discusses using the humidity sensor on the PCB and using the software PC Application Chapter 4 Modified Circuit Gives the modifications necessary to i...

Page 6: ...Bold characters A dialog button Click OK A tab Click the Power tab N Rnnnn A number in verilog format where N is the total number of digits R is the radix and n is a digit 4 b0010 2 hF1 Text in angle...

Page 7: ...ers MCUs and dsPIC Digital Signal Controllers DSCs AN1016 Detecting Small Capacitive Sensors Using the MCP6291 and PIC16F690 Devices DS01016 Explains the functionality and design of this board s circu...

Page 8: ...icrochip consultant program member listing Business of Microchip Product selector and ordering guides latest Microchip press releases listing of seminars and events listings of Microchip sales offices...

Page 9: ...d s functionality and to verify its accuracy 1 3 HUMIDITY SENSOR PICTAIL DEMO BOARD The circuit operation is detailed in AN1016 Detecting Small Capacitive Sensors Using the MCP6291 and PIC16F690 Devic...

Page 10: ...key points in the circuit using common lab equipment The test points are GND Is connected to ground plane and is for any lab equipment 5V Positive supply voltage at board edge it provides a means to p...

Page 11: ...connection to devices that program the on board PIC16F690 such as the MPLAB ICD 2 DV164005 and the PICkit 2 Microcontroller Programmer DV164120 1 4 4 PICkit 1 Flash Starter Kit The PICkit 1 Flash Star...

Page 12: ...d in 1 5 ASSEMBLY CODE MODULES The following assembly code modules for the PIC16F690 make up the Humidity Sensor project main inc contains I O port and global defines used throughout the project main...

Page 13: ...2 0 2 or later The PICkit 1 Flash Starter Kit CD ROM DS40049 contains many of the necessary files The capacitance exe PC program comes with the Humidity Sensor PICtail Demo Board CD ROM Version v1 07...

Page 14: ...after it is plugged in The PIC16F690 comes with the 00084R1 hex file already programmed 2 3 3 Humidity Sensor PC Program 1 Run the installer program AN1016 install exe which places the executable fil...

Page 15: ...FIGURE 2 2 Board Connections for PICkit 2 Microcontroller Programmer 2 4 2 MPLAB ICD 2 An exploded view of how the MPLAB ICD 2 connects to the Humidity Sensor PICtail Demo Board is shown in Figure 2...

Page 16: ...Humidity Sensor PICtail Demo Board User s Guide DS51594A page 12 2005 Microchip Technology Inc NOTES...

Page 17: ...to the measurement resolution and capacitance values desired see Table 3 1 4 Allow sufficient time for the humidity sensor to respond to changes in the environment about 30 seconds for the HS1101LF TA...

Page 18: ...Humidity RH a Put the HS1101LF sensor in CSEN s socket on the board b Select the 0 1 pF count resolution on the board put shunt across JP1 c Click on the READ HUMIDITY button a resolution of 0 1 pF c...

Page 19: ...Many reputable companies provide humidity calibration equipment and or services There are two common approaches to calibrating these sensors 1 Put sensor in an atmosphere with well controlled RH 2 Use...

Page 20: ...Humidity Sensor PICtail Demo Board User s Guide DS51594A page 16 2005 Microchip Technology Inc NOTES...

Page 21: ...s performance 4 2 THE REDUCED CURRENT CIRCUIT 4 2 1 Modifications Figure 4 1 shows the Humidity Sensor PICtail Demo Board top silk screen Figure 4 1 also shows the locations of the resistors that need...

Page 22: ...Program The capacitance exe PC program displays measured capacitance values assuming the Humidity Sensor PICtail Demo Board has not been modified To correct the dis played values move the displayed d...

Page 23: ...1 sends a square wave at its pin 14 to the input of the integrator The integrator converts it to a triangle wave which is seen at the microcontroller s pin 15 There is a comparator internal to U1 whic...

Page 24: ...and Chapter 4 Modified Circuit A 5 ADDITIONAL COMMENTS The demonstration board includes test points for convenience on the bench The 5V and GND test points TP1 and TP2 connect to the board s supply vo...

Page 25: ...P1C RC6 AN8 SS RC7 AN9 SDO RB7 TX CK 20 19 18 17 16 15 14 13 12 11 RA0 AN0 C1IN ICSPDAT ULPWU RA1 AN1 C12IN VREF ICSPCLK RA2 AN2 T0CLKI INT C1OUT RC0 AN4 C2IN RC1 AN5 C12IN RC2 AN6 P1D RB4 AN10 SDI S...

Page 26: ...oard Schematic Continued RA3 RA1 RA0 P1 P2 ICSP NOTE All Resistors are 1 TP2 GND TP1 5V 5VA R5 100 5V C3 1 F C4 1 F RA5 RA4 RA3 RC5 RC4 RC3 RA0 RA1 RA2 RC0 RC1 RC2 5V GND 1 2 3 4 5 6 7 8 9 10 11 12 13...

Page 27: ...Schematic and Layouts 2005 Microchip Technology Inc DS51594A page 23 FIGURE A 3 Board Top Silk Screen FIGURE A 4 Board Top Metal Layer...

Page 28: ...Humidity Sensor PICtail Demo Board User s Guide DS51594A page 24 2005 Microchip Technology Inc FIGURE A 5 Board Bottom Metal Layer...

Page 29: ...used left open Note 1 1 R5 Chip Resistor 100 1 8W 1 0805 SMD Yageo America RC0805FR 07100RL 3 R2 R4 Chip Resistor 10 0 k 1 8W 1 0805 SMD Yageo America RC0805FR 0710KL 2 RCM1 RCM2 Chip Resistor 20 0 k...

Page 30: ...rcuit modifications discussed in application note AN1016 and Chapter 4 Modified Circuit TABLE B 3 BILL OF MATERIALS FOR REDUCED CURRENT MODIFICATIONS Qty Reference Description Manufacturer Part Number...

Page 31: ...Bill Of Materials BOM 2005 Microchip Technology Inc DS51594A page 27 NOTES...

Page 32: ...3 China Shenzhen Tel 86 755 8203 2660 Fax 86 755 8203 1760 China Shunde Tel 86 757 2839 5507 Fax 86 757 2839 5571 China Wuhan Tel 86 27 5980 5300 Fax 86 27 5980 5118 China Xian Tel 86 29 8833 7250 Fax...

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