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SMSC EMC2102 User's Manual

1. 12 Figure 5 6 Plotting from the ChipMan 12 FIGUIE 5 6 Plot Examples EA exe eed ooh te shod beeen TP e C dca qe De e doit de d ee bas 13 Figure 5 7 Plot WINGOWS IIIA ew Roo ed e 2 dioa painaa ORAS Oe Oe oa S 13 Figure 5 9 Plots for Proper Control Settings 14 Figure 5 10 Effects of Loading 15 Figure 5 11 Fan Control Parameters 16 Figure 5 12 Forced Kick Function 17 Figure 5 13 60 Spin Level Setting 18 Figure 5 14 Reduced Spin up Time 18 Figure 5 15 Default RampRate 20 Figure 5 16 Default Step Size with Different UPDATE Settings 21 Figure 5 17 Default UPDATE with Different Step Size Settings 21 Figure 5 18 Exceptionally Slow Rate 22 Figure 5 19 Update Time Modifications 23 Figure 5 20 Minimum Drive Setting 24 Figure 5 21 Valid Tach Count Setting 24
2. 36 6 2 1 General Setup n 36 6 2 2 Set the Correct LIMIT2K Value 37 6 2 3 Determine the Number of Poles and the Maximum Fan Speed 37 6 2 4 Determine the Minimum Startup Speed 37 6 2 5 Determine the StallSpeed 37 6 2 6 Determine the Minimum Valid TACH Speed 37 6 2 7 Determine the Spin up Levels rom60 andrpm75 38 Revision 0 2 09 17 07 USER MANUAL SMSC EMC2102 2 Fan Speed Control with the EMC2102 Device 6 2 8 Using the Tested Parameters SMSC EMC2102 USER MANUAL Revision 0 2 09 17 07 3 Fan Speed Control with the EMC2102 Device P SMST List of Figures Figure 4 1 EMC2102 Fan Control Evaluation System 7 Figure 4 2 EVB EMC2102 Board 7 Figure 5 1 ChipMan Message for First Operation 8 Figure 5 2 ChipMan Device Selection Window 9 Figure 5 3 Selecting the Device and Master Controller Type 10 Figure 5 4 ChipMan Operation Window 10 Figure 5 5 ChangingFanSpeed
3. Fan Driver Setting Configuration Status FAN Configuration FCONFIG SMBUS Add Registerisi to Plot Temperature Standard Format FAN Spin Up Configuration FSPIM SMBUS Temperature Offset Format FAN Step l FSTEP SMBUS Fan Settings FAN Minimum Drive FMIMDR SMBUS Valid TACH Count VTACH SMBUS ru TACH Target TTARG SMBUS TACH Reading FT ACH SMBUS Figure 5 6 Plotting from the ChipMan Revision 0 2 09 17 07 USER MANUAL SMSC EMC2102 12 Fan Speed Control with the EMC2102 Device E Rogistor value or NA E fan speod RPM Block Address Name yp Block Address Name Plot lin 5 Fan Orive HE A TACH i ee mre ee se PPP Pr aa time sec Peeper time ec Time per divisian in Time per divishon in o Figure 5 7 Plot Windows The two plots shown in Figure 5 8 Plot Examples are in sync If the scaled data is desired for analysis or archival the data may be stored in a semi colon separated text file from each of the plot windows Simply select File Export and enter a filename in the Save window Wl Register value Hex imme TACH Reading 58h ih i TACH Target 57h Ume sec time sec Time per divisioni Time per division 5s Figure 5 8 Plot Examples 5 2 Experiment 2 RPM Based Closed Loop Fan Control The experiment 2 is designed to gain familiarity with the closed loop RPM controller implemented in the EMC2102 This experiment will discuss the effects of gain
4. Fan Speed Control with the EMC2102 Device W Register value Hex DEAR E Fan speed RPM File Options view Control File Options View Control time sec time sec Time per division bs Time per division Iss Figure 5 10 Effects of Loading 5 2 4 Register Change Summary Table 5 1 Register Change Summary for Experiment 2 lists all register value changes from the default cmf load to accomplish the tests Table 5 1 Register Change Summary for Experiment 2 REGISTER DEFAULT NEW NAME ADDRESS VALUE VALUE COMMENT Fan 52h 4Bh CBh Enables the RPM based closed loop fan Configuration 0100 1011b 1100 1011b control Algorithm SMSC EMC2102 USER MANUAL Revision 0 2 09 17 07 15 Fan Speed Control with the EMC2102 Device P SMSE 5 3 Experiment 3 Spin up Configuration Options This experiment is designed to gain familiarity with the various spin up options available in the EMC2102 devices This experiment will discuss the effects of Spin Up Time and Spin Up Levels These parameters are important to ensure a valid start while minimizing the turn on overshoot for initial low RPM settings More examples regarding these two parameters can be found in Section 5 7 1 Repetitious Spin up Routine Caused by Incorrect Settings The CMF file for this experiment is the same as for Experiment 1 EMC2102 default cmf 5 3 1 Fan Control Parameters The spin up routine is a special algorithm that the EMC2102 uses t
5. spin up and minimum settings on the closed loop performance The cmf file for this experiment is EMC2102_RPM cmf 5 2 1 Getting Started For all these tests the Fan Drive Setting register 51h the TACH Target register 57h and the TACH Reading registers 58h are selected to plot As bits are switched in each of the tests the register name and address will be provided SMSC EMC2102 USER MANUAL Revision 0 2 09 17 07 13 P SMSE 5 2 2 5 2 3 Fan Speed Control with the EMC2102 Device Basic RPM Based Fan Control The EMC2102 defaults will enable closed loop operation Prior to other options examine the various parameters on ChipMan window page 3 Fan Settings The registers of most interest are the FAN Minimum Drive 55h and Valid Tach Count 56h The closed loop controller will not drive below the minimum drive value and will not respond to a TACH Target RPM speed less than the speed defined by the Valid Tach Count register Note The TACH reading is a reciprocal function of the fan speed i e a higher TACH reading value means a slower fan rpm speed Refer to 6 Appendix for more details Same as Experiment 1 select Fan Drive Setting 51h TACH Target 57h and TACH Reading 58h for plotting Start the plot windows in order to see the response and command a series of Tach Targets starting at 4500 RPM and going up in 500 RPM steps The plots in Figure 5 9 Plots for Proper Control Settings will be representat
6. 30 time sec Time per division CERE X Time per division is X Figure 5 28 Spin up Case 2 5 7 1 3 Case 3 Valid RPM lt Target RPM lt lt Spin up Level RPM In this case the target speed is only a little greater than the valid speed and both of them are much smaller than the spin up level speed rom60 or rom75 The theoretical plot of this situation is shown in Figure 5 29 Theoretical Plot of Case 3 Fan Speed RPM RPM for 100 Drive rpm60 or rpm75 Fan Speed J Target Speed Valid Speed opin Up Time Check TACH Figure 5 29 Theoretical Plot of Case 3 Since the fan speed at the end of spin up routine is higher than the minimum valid speed the EMC2102 should go to the normal operation after the spin up routine However because the large speed difference between the spin up level speed rpm60 or rpm75 and the target speed the closed loop controller will try to make a big adjustment of its output to reach the target speed With incorrect settings such as big output step or short update time this adjustment could easily cause an undershoot and make the fan speed below the valid rpm and than make the spin up routine restart SMSC EMC2102 USER MANUAL Revision 0 2 09 17 07 31 Fan Speed Control with the EMC2102 Device P SMSE Using the EVB EMC2102 to test this situation with rpm75 25650 rpm simply set the Valid TACH register 56h with 4500 rpm set the UPDATE 52h 2 0 100ms and start
7. 4 Register Change Summary for Experiment 7 REGISTER DEFAULT NEW NAME ADDRESS VALUE VALUE COMMENT Fan 52Bh BENE Disable RPM based fan control algorithm Configuration C8h CFh CFh Demonstrate UPDATE effect UPDATE effect Valid Tach ax ie LI orici MM from 2010 RPM to 5000 RPM to show Count the effect in closed loop SMSC EMC2102 USER MANUAL Revision 0 2 09 17 07 25 Fan Speed Control with the EMC2102 Device P SMSE 5 6 Experiment 6 Limits and Alerts This experiment is designed to gain familiarity with the control registers for generating fan related alarms and alerts associated with the EMC2102 The CMF file for this experiment is EMC2102 default cmf 5 6 1 General Setup For all these tests the Fan Drive Setting register 51h the TACH Target register 57h and the TACH Reading registers 58h are selected to plot As bits are switched in each of the tests the register name and address will be provided 5 6 2 Fan Spin and Stall Interrupts The Configuration Status page in the ChipMan application contains all the Interrupt configuration and status registers for the fan In this experiment the Fan Stall and Fan Spin status bits will be checked In order to see the status bits change the Interrupt Status 2 register 23h is plotted along with other registers listed above The Interrupt Mask register 24h should be set to 10h default for this set of experiments Start the plotting function within ChipMa
8. Fan speed RPM Legend Block Address Name HwM 57 TACH Target HwM 55 Valid TACH Count HwM 58 TACH Reading Plot line type 1324 20 time sec Time per division 2 n E Figure 5 25 Spin up Case 1 Fix 1 If the fan is already set to 75 level we will need to lower the valid speed function of 56h Valid TACH to a value below the rpm75 to fix the problem To test this situation set spin up level to 75 53h 2 1 set the Valid TACH Count 56h 6000 rpm and then start the fan 57h with 6500 rpm The spin up routine will run repeatealy Change the Valid TACH Count 56h to 5800 rpm the problem cannot be fixed since the valid speed is still higher than the fan speed rpm75 5650 rpm Set 56h 5580 rpm which is below 5650 rpm the rpm75 the system gets out of the spin up routine Figure 5 26 SMSC EMC2102 USER MANUA 29 L Revision 0 2 09 17 07 Fan Speed Control with the EMC2102 Device pa Register value Hex Register value Hex Legend EJ ll Fan speed RPM Fan speed RPM Legend EJ Block Address Name Plot line type Block Address Name Plot line type File Options View Control HWM 51 Fan Driver Setting File Options View Control HwM 57 TACH Target HwM 53 FAN Spin Up Configuration HWM 56 Valid TACH Count S000 HWM 58 TACH Reading 7500 Valid Speed 6000 rpm 6500 Fan Drive Setting 51h WA ai Trac MUS JN Perf m 5500 tt om Valid Speed 558
9. Figure 5 22 Fan SpinandStall 27 Figure 5 23 Fan Spin up Routine Restarted Repeatedly 28 Figure 5 24 Theoretical Plot of Case 1 29 Figure 5 25 Spin up Gase 1 FIX T sa uu cies 9 due dg oh Ou od 3d deem d dera ierta itat cured s 29 Figure 5 26 Spin up Case 1 FiK2 30 Figure 5 27 TheoreticalPlotofCase2 30 Figure 5 28 Spin up Case 2 31 Figure 5 29 Theoretical Plot of Case 3 31 Figure 5 30 Spin up Case 3 32 Figure 5 31 Spin up Routine Restarted During Normal Operation 32 Figure 5 32 TheoreticalPlotofCase4 33 Figure 5 33 Spin up GaSe 2454545245804 506 54666 6566604 ed Rode d WueOS a edd Rd dac ded d 33 Figure 5 34 Spin up Case 5 34 Figure 5 35 Spin up Case 5 Fik 34 Figure 6 1 A Typical 2 pole DC Fan 35 Figure 6 2 Output Signal of a2 pole Fan 35 Figure
10. Setup For all these tests the Fan Drive Setting register 51h and the TACH Reading registers 58h are selected to plot As bits are switched in each of the tests the register name and address will be provided 5 4 2 Controlling the Ramp Rate Controlling the ramp rate can improve the performance of the fan control loop by limiting the slew rate of the fan drive The EMC2102 uses the UPDATE bits in the FAN Configuration register 52h bits 2 0 to determine the time interval between two updates of the controller output and uses the FAN Step register 54h to determine the maximum allowed hexadecimal count STEP of the output Refer to Figure 5 11 Fan Control Parameters for more details These two parameters can only work in the RPM control mode When the RPM control function is disabled 52h 7 0 any change in the Fan Drive Setting register b1h will immediately change the output The plots in Figure 5 15 Default Ramp Rate illustrate the drive and response with the default UPDATE 400ms and default STEP SIZE Max 16 drive settings per update while changing the fan target speed from 4000 rpm to 6000rpm W Register value Hex lil Fan speed RPM File Options View Control File Options View Control time sec i time sec Time per division m Time per division Figure 5 15 Default Ramp Rate The ramping rate in this mode can be accelerated or slowed down depending on application and the values of register 52h UPDA
11. XML files conforming to XML Version 1 0 and Encoding utf 8 The data files for downloading values to the device are CMF files specific to the ChipMan application The CMF files may be located anywhere on the hard drive but the XML files MUST reside in the ChipMan directory typically located at C Program Files SMSC ChipMan Chips An XML file usually names with the device name that supports EMC2102 xml EMC2103 2 xml etc During the installation of the ChipMan application it is possible to specify a non default installation directory If this was done substitute the path provided at that installation for C Program Files to store the XML files in the proper location Connect the USB cable to an available USB port on the PC The other end mini B end of the USB cable should be connected to an EMC Evaluation Board The Find New Hardware wizard will pop up on the PC s screen for USB driver installation Follow the instructions on the screen to complete the installation process 5 1 2 Setting Up the ChipMan Once the ChipMan has been installed start the software by selecting Start gt Programs gt SMSC gt Chip Manager If this is the first operation the application will guide you to select a device as shown in Figure 5 1 below Chip Manager No SMSC device has been selected Would wou like bo select a device Figure 5 1 ChipMan Message for First Operation Answer Yes then the device selection menu as shown
12. changed to 01h Figure 5 18 Exceptionally Slow Rate Note the large scale of the Time per division in the figure SMSC EMC2102 USER MANUAL Revision 0 2 09 17 07 21 Fan Speed Control with the EMC2102 Device lil Register value Hex TAR ll Fan speed RPM File Options View Control File Options View Control time sec time sec Time per division EB Time per division 99 Figure 5 18 Exceptionally Slow Rate 5 4 3 Register Change Summary Table 5 3 Register Change Summary for Experiment 4 lists all register value changes from the default cmf load to accomplish the tests Table 5 3 Register Change Summary for Experiment 4 REGISTER DEFAULT NEW NAME ADDRESS VALUE VALUE COMMENT FAN Step T ih Oth Demonstrate RRC Demonstrate RRC longduration duration Fan CFh Demonstrate min WA AA eer and maz CFh UPDATE rates Configuration applied to RRC Revision 0 2 09 17 07 USER MANUAL SMSC EMC2102 22 Fan Speed Control with the EMC2102 Device E gt Smsc 5 5 Experiment 5 Optimizing RPM Control Response This experiment is designed to gain familiarity with the parameters that affect the closed loop controller implemented in the EMC2102 All these registers are located on the Fan Setting page in ChipMan This experiment will go through each register examining the effects of parametric changes on the closed loop controller in RPM mode 5 5 1 General Setup For all these tes
13. examine this feature set the minimum drive to COh and command an RPM setting of less than 5500 RPM The fan will start at about 5600 rpm 51h COh Set the target to 6000 rpm and the fan speed follows Drop the fan target speed from 6000 rpm to 4500 rpm the real fan speed will only drop to about 5560 rpm as shown in Figure 5 20 Minimum Drive Setting W Register value Hex lil Fan speed RPM File Options View Control le Options View Control Fan starts at 5 oe Minimum Drive 9000 Fan will not run below Minimum Drtive h 1000 time sec 03 00 time sec Time per division Time per division Figure 5 20 Minimum Drive Setting Likewise the Valid TACH Count register operation is simple to show Start the fan at 6000 RPM with all default setting and then set the Valid TACH register to 5000 RPM Enter a command of 4800 RPM and the fan will not respond as shown in Figure 5 21 Valid Tach Count Setting li Register value Hex CH B Ei Fan speed RPM File Options View Control File Options View Control time sec time sec Time per division De oo Time per division Rs Figure 5 21 Valid Tach Count Setting Revision 0 2 09 17 07 USER MANUAL SMSC EMC2102 24 Fan Speed Control with the EMC2102 Device E gt SMSE 5 5 4 Register Change Summary Table 5 4 Register Change Summary for Experiment 7 lists all register value changes from the default cmf load to accomplish the tests Table 5
14. step by step Monitor the rpm values in the TACH Reading register 58h a Using an oscilloscope to observe the fan s Tachometer signal a When invalid the TACH signal will become erratic with incorrect values usually much less TACH counts or very high rpm in register 58h s The TACH signal may be valid until the fan stalls If it happens the fan s stall speed could be used as the minimum valid TACH speed SMSC EMC2102 USER MANUAL Revision 0 2 09 17 07 37 E gt SMSE Fan Speed Control with the EMC2102 Device 6 2 7 Determine the Spin up Levels rpm60 and rpm75 a Drive the fan with 60 of the maximum output register 51h 99h and the rpm value in the TACH Reading register 58h will be the fan s rpm60 Drive the fan with 7596 of the maximum output register 51h BFh and the rpm value in the TACH Reading register 58h will be the fan s rpm75 6 2 8 Using the Tested Parameters All parameters discussed above will vary from fan to fan and with fan aging therefore some margins have to be added when selecting the fan control settings A minimum of 1096 of full fan speed is recommended for margins 6 2 8 1 Spin up LEVEL Register 53h 2 This parameter has to be set so that the corresponding fan speed is greater than Minimum Startup Speed Margin 6 2 8 2 Minimum Fan Speed To avoid stalling the fan speed a function of Fan Driver Setting 51h or a function of TACH Target 57h needs to be greater than Stall Speed Margin at all
15. the fan with 4700 rpm the spin up routine starts over and over Figure 5 30 Spin up Case 3 To fix this problem change the UPDATE 52h 2 0 back to 400 ms It will give the fan more time to reach the speed of the previous step and reduce the overshoot undershoot Another solution is to decrease the Fan Step settings which will force the controller to take smaller steps to achieve the target speed When the target speed is too close to the valid speed the problem will not only occur when the fan starts It may also cause problems in the normal operation after the spin up since the fan speed reading errors caused by fan load changes tachometer truncation errors circuit noises etc could drop it below the valid speed and cause a spin up routine restart Figure 5 31 Spin up Routine Restarted During Normal Operation W Register value Hex Register value Hex Legend EJ ll Fan speed RPM Fan speed RPM Legend EJ Fie Options View Control Hess Airce Pees File Options View Control Block Address Plot ine type Boek Ades Name L Petieiesli fe Options wew c TENE age HwM 56 Valid TACH Count 255 Hw 58 TACH Reading EE UPDATE 400 ms iT i UPDATE 100 ms 100 3 90 time sec time sec Time per division 2 s v Time per division 2 E Register value Hex Seles File Options View Control Options View Control c 1003360 time sec cj 40003360 time sec Time per division m Time
16. times 6 2 8 3 Valid TACH Count Speed Function of Register 56h The EMC2102 will not respond to any TACH Target 57h value that has a corresponding speed slower than Minimum Valid TACH Speed Margin unless the value is FFh which will stop the fan This ensures that the RPM control algorithm will not drive too low 6 2 8 4 Maximum Fan Speed Use the measured maximum fan speed minus margin as the Maximum Fan Speed Revision 0 2 09 17 07 USER MANUAL SMSC EMC2102 38
17. 0 rom x time sec 3000 4 60 time sec Time per division Eu Time per division Figure 5 26 Spin up Case 1 Fix 2 5 7 1 2 Case 2 Valid RPM lt lt Target RPM lt Spin up Level RPM In this case the target speed is smaller than the spin up level speed rpm60 or rpm75 and is much bigger than the valid speed The theoretical plot of this situation is shown in Figure 5 27 Theoretical Plot of Case 2 Since the fan speed at the end of spin up routine is always higher than the minimum valid speed the EMC2102 will go to the normal operation after the spin up routine Using the EVB EMC2102 to test this situation with rpm75 5650 rpm simply set the Valid TACH register 56h with 4500 rpm and start the fan with TACH Target 57h 5500 rpm Figure 5 28 Spin up Case 2 Fan Speed RPM RPM for 100 Drive rpm60 or rpm75 Fan Speed Target Speed Valid Speed Spin Up Time Check TACH Figure 5 27 Theoretical Plot of Case 2 Revision 0 2 09 17 07 USER MANUAL SMSC EMC2102 30 Fan Speed Control with the EMC2102 Device W Register value Hex Register value Hex Legend x L Fan speed RPM Fan speed RPM Legend EJ Ele Options View Control Block Address Name Plotline type Ele Options View Control Block Address Name Plot line type HwM 51 Fan Driver Setting HWM 57 TACH Target HwM 55 Valid TACH Count HWM 58 TACH Reading Fan Drive Setting 51h time sec 83
18. 2 EXT INT pwr SEL Wien d Tim MET uL BBCUK EM 2102 Sv Lii BL oss 77 e i kae TP7 TtPie HCR cdd R35 Cl U6 MEN exe eA P13 Aa Lt kcu uu i 8i x cL ALERT r il ABLE CH i L OPEN CH 3 PWR PWR THRM SHDN RES OK TRIP SEL w 9 P4 O Figure 4 2 EVB EMC2102 Board SMSC EMC2102 USER MANUAL Revision 0 2 09 17 07 7 Fan Speed Control with the EMC2102 Device E gt SMSE 5 Basic Operation Experiments In this chapter basic operation experiments will be provided to help users to get familiar with the system 5 1 Experiment 1 Manual Fan Control This experiment is designed to gain familiarity with both the EMC2102 device and the application software ChipMan The ChipMan application can be used to configure the EMC2102 device and to monitor the status of the device It includes tools to capture and plot data at rates up to 10Hz Additionally ChipMan can be used to review previously saved data 5 1 1 ChipMan Installation Install the ChipMan application and device driver on a PC by running Setup exe from the EMC2102 Evaluation System Software CD provided by SMSC A revision history and install uninstall notes may be found in the readme txt file on the disk ChipMan uses definition files and data files to identify the devices it supports to load specific values into registers and monitor plot or record the values of any register set in the device ChipMan definition files are
19. 6 3 Fan TACH Measurement With EMC2102 36 Revision 0 2 09 17 07 USER MANUAL SMSC EMC2102 4 Fan Speed Control with the EMC2102 Device List of Tables Table 5 1 Register Change Summary for Experiment 2 Table 5 2 Register Change Summary for Ekperiment3 19 Table 5 3 Register Change Summary for Ekperiment4 22 Table 5 4 Register Change Summary for Ekperiment7 25 SMSC EMC2102 USER MANUAL Revision 0 2 09 17 07 5 Fan Speed Control with the EMC2102 Device P SMSE 1 Overview SMSC has introduced a series of Environmental Monitoring and Control EMC devices with integrated fan control This fan controller family devices feature the advanced closed loop fan control technology developed by SMSC s engineering team This user manual provides detailed information about fan control features supported by one of those EMC devices EMC2102 with detailed hand on experiments for configuring the devices in real applications 2 Audience This user manual assumes that the reader is familiar with the functionality of the EMC2102 device and its evaluation board The goal of the user manual is to help users to evaluate the new EMC device using Chip Manager ChipMan software provided by SMSC This user manual also can be used as a reference material for other EMC devices which have fan control featu
20. 8 GEO ER EI EE a CUN ER EC HOUR CUR PU PCR OR 1d 6 Z UA IAA E SANI T E E E T OTE E 6 3 References 6 4 The Evaluation System 6 5 Basic Operation Experiments 8 5 1 Experiment 1 Manual Fan Control 8 5 1 1 Chip Man Installation sac doxes aci etch en ah ah a riconosce UC S dise se ar t c Ie t 8 5 1 2 Setting Up the ChipMan 8 9 1 3 Plotting From ChipMan 12 5 2 Experiment 2 RPM Based Closed Loop Fan Control 13 5 2 1 GENN dagean gh te a a ine hee ead aa Ske ws ares Se eee ee 13 5 2 2 Basic RPM Based Fan Control 14 5 2 3 Effects of Loading 14 5 2 4 Register Change Summary 15 5 3 Experiment 3 Spin up Configuration Options 16 5 3 1 Fan Control Parameters 16 5 3 2 Getting Started 17 5 3 3 Forced Kick Function 17 5 3 4 SOU OG C CT 17 5 9 5 Sp
21. EDGES value in register 52h has to be modified or all speed readings displayed by ChipMan have to be re calculated using Equation 1 s The value in 58h also can be compared to the fan s tachometer output frequency obtained by an oscilloscope to verify its correctness Record the rpm values in the TACH Reading register 58h as the maximum fan speed s The maximum fan speed for the EVB EMC2102 on board DC fan is about 7000 rpm 6 2 4 Determine the Minimum Startup Speed s Set the device in Manual Mode 52h 7 0 a Write a value for example 80h to Fan Driver Setting register 51h lf the fan cannot start then increase the drive value until the fan start a If the fan starts at the first drive value then stop the fan 51h 0 and write a smaller value to register 51h Repeat the above steps until the minimum startup speed is determined Record the drive value in 51h and the fan speed in register 58h s The minimal start speed for the EVB EMC2102 on board DC fan is about 4500 rpm with output drive of 9Eh 6 2 5 Determine the Stall Speed s While the fan is running reduce the fan drive value in register 51h step by step until the fan stops s Write down the drive value in 51h and the fan speed in register 58h before the fan stops The stall speed for the EVB EMC2102 on board DC fan is about 3000 rpm 70h 6 2 6 Determine the Minimum Valid TACH Speed s While the fan is running in non RPM mode reduce the fan drive value in register 51h
22. RPM Drive Mode Rate Controls This parameter is independent of the TACH Reading updates which are controlled by the EDGES 1 0 parameter The plots in Figure 5 19 Update Time Modifications show the effect of UPDATE on the closed loop performance when starting the on board fan The numbers in unit of second in the left plot indicate the UPDATE value used for that sequence By experimenting with the different update times you can determine the most stable setting for the fan to be controlled E Register value Hex lil Fan speed RPM File Options View Control File Options View Control B000 72007 64007 0 1s 0 2s 0 4s 0 8s 1 6s 5600 4800H um 4000 HE a 3200H 2400H Invalid TACH signals E IE Ignored 2 TT 4 0 268 50 time sec 368 50 m 0 268 50 time le 368 50 Time per division Time per division 405 Figure 5 19 Update Time Modifications SMSC EMC2102 USER MANUAL Revision 0 2 09 17 07 23 Fan Speed Control with the EMC2102 Device P SMST 5 5 3 FAN Minimum Drive Register 55h and Valid TACH Count 56h These two registers assist the user in defining the operational environment for a given fan The Minimum Drive register is an absolute minimum value the RPM controller may drive to in an attempt to achieve low RPM settings The Valid Tach Count register is used to compare against the Tach Target register No value less than the Valid Tach Count will be accepted by the controller To
23. SIMSC SUCCESS BY DESIGN Fan Speed Control with the EMC2102 Device Copyright 2007 SMSC or its subsidiaries All rights reserved Circuit diagrams and other information relating to SMSC products are included as a means of illustrating typical applications Consequently complete information sufficient for construction purposes is not necessarily given Although the information has been checked and is believed to be accurate no responsibility is assumed for inaccuracies SMSC reserves the right to make changes to specifications and product descriptions at any time without notice Contact your local SMSC sales office to obtain the latest specifications before placing your product order The provision of this information does not convey to the purchaser of the described semiconductor devices any licenses under any patent rights or other intellectual property rights of SMSC or others All sales are expressly conditional on your agreement to the terms and conditions of the most recently dated version of SMSC s standard Terms of Sale Agreement dated before the date of your order the Terms of Sale Agreement The product may contain design defects or errors known as anomalies which may cause the product s functions to deviate from published specifications Anomaly sheets are available upon request SMSC products are not designed intended authorized or warranted for use in any life support or other application where product failure could cause or con
24. SPINUP TIME 2s and restart the fan with 5500 rpm Increasing Spin up time will make a longer 100 kick time and provide the fan with more power to speed up Figure 5 35 Spin up Case 5 Fix The problem also can be fixed by changing the spin up level from 60 to 75 if not done already as previously discussed Register value Hex Register value Hex Legend EJ E Fan speed RPM Fan speed RPM Legend ES File Options View Control Block Address Name Plot line type Block Address Name Plot line type HwM 51 Fan Driver Setting Elle Options View Control Hw 57 TACH Target HWM 565 Valid TACH Count HwM 58 TACH Reading p ed 4 Longer 100 kick provides more i driving power to speed up the fan 7 fll time sec zx 06 40 time sec Time per division 1 s Time per division 1 s x Figure 5 35 Spin up Case 5 Fix Revision 0 2 09 17 07 USER MANUAL SMSC EMC2102 34 Fan Speed Control with the EMC2102 Device P SMSE 6 Appendix 6 1 DC Fan Basics Poles Tach Meter Pulses and Edges An n pole fan has n pairs of North South magnetic poles which are generated by electromagnet coils At anytime only one pair of coils are driven and which coil pair gets driven is determined by a component called Hall Sensor The architecture of a typical 2 pole DC fan is shown in Figure 6 1 A Typical 2 pole DC Fan Protection Hall Sensor Figure 6 1 A Typical 2 pole DC Fan The output of t
25. TE and 54h STEP SIZE In the next experiment Figure 5 16 Default Step Size with Different UPDATE Settings the default STEP SIZE with different UPDATE 400 ms and 100 ms were used The 100 ms setting has the effect of speeding the loop up by a factor of 4 as that is the ratio between minimum 100ms and default 400ms UPDATE settings Revision 0 2 09 17 07 USER MANUAL SMSC EMC2102 20 Fan Speed Control with the EMC2102 Device a Register value Hex DE E Fan speed RPM DER Fie Options View Control File Options View Control LLL LL LL FI 7 time sec time sec Time per division Bs v Time per division 5s Figure 5 16 Default Step Size with Different UPDATE Settings In the next experiment Figure 5 17 Default UPDATE with Different Step Size Settings two different maximum step sizes 16 and 63 were used with the 63 STEP SIZE setting the output takes less steps updates from 4000 rpm to 7500 rpm because it gives the fan more power to follow the desired rpm settings lil Register value Hex Sel E Fan speed RPM DE File Options View Control File Options View Control id 3000 eee Ea NA time sec i l time sec Time per division Bs Time per division 5 3 Figure 5 17 Default UPDATE with Different Step Size Settings In the last experiment an extremely slow ramp rate is demonstrated The UPDATE was set to maximum 1600 ms and the STEP SIZE was
26. e EMC2102 Device Fan speed RPM Legend ES Address Name gu Plot line type HwM 57 TACH Target HwM 58 TACH Reading Register value Hex Legend EJ Block Address Name Plot line type Hw 51 Fan Driver Setting E Fan speed RPM File E Register value Hex File Options View Control Options View Control time sec Time per division X time sec Time per division Figure 5 13 60 Spin Level Setting Note When a fan starts the first TACH count captured by the EMC2102 may not reflect the fan s speed correctly since the counting clock 82 768 kHz could only partially fill the counting window which will cause a higher speed reading Also for some fans the tachometer may not work immediately after the fan starts therefore some invalid TACH signals very short noisy pulses could be sent out at the beginning In either case the invalid TACH counts could be displayed on the ChipMan plots Figure 5 13 but will never be used to control the fan because the EMC2102 will not look at the TACH reading until the end of spin up routine 5 3 5 Spin Up Time The EMC2102 FAN Spin Up Configuration register 53h contains 2 bits to set the overall spin up time This parameter allows for tailoring of rapid and slow response fans Repeat the experiment in Section 5 3 3 with 500 ms SPINUP_TIME This will provide a quicker response with smaller overshoot as shown in Figure 5 14 Reduced Spin up Time In general s
27. e fan 5 EDGES 3 EDGES Fan Tach Signal 7 EDGES 32 768kHz J Clock n EDGE WINDOW lt gt TwiNDOW Figure 6 3 Fan TACH Measurement With EMC2102 ChipMan translates TACH counts to the RPM value and displays the fan speed For applications not using ChipMan software the following equation can be used to convert the TACH Reading values to the real RPM speeds where EDGES f 2h 4 EDGES 1 983040 GES number of edges set by register 52h 4 3 RPM Poles COUNT COUNT TACH Reading 58h value 1 Poles number of pole pairs in the DC fan m factor defined by LIMIT2K 52h 6 m 1 for 500 rpm and m 4 for 2000 rpm 6 2 Characterizing a DC Fan with EVB EMC2102 and ChipMan As a very important component in the closed loop the DC fan s characteristics have a great impact on the control system s performance Using the EVB EMC2102 and ChipMan software tool a 5V DC fan s characteristics can be easily tested In general the following parameters need to be characterized Minimu
28. evice Remote SMSC Device EMC2102 LPC Bus Settings SMBus Settings Slave Addresses Block Registers Slave Address 20 FF Select automatically Master Controller USB SMBus Bridge Simulation Mode Figure 5 2 ChipMan Device Selection Window SMSC EMC2102 USER MANUAL Revision 0 2 09 17 07 9 P SMST Select SMSC Device Device Remote Fan Speed Control with the EMC2102 Device Select SMSC Device Device Remote SMSC Device rucoqgp v SMSC Device EMC2102 v EMC2102 LPC Bus Settings SMBus Settings LPC Bus Settings SMBus Settings Slave Addresses Slave Address Slave Addresses Slave Address TA T 20 FF Select automatically Master Controller USB SMBus Bridge v Simulation Mode 20 FF Select automatically Master Controller USB SMBus Bridge 170 Controller Hub USB SMBus Bridae Simulation Mode tee Figure 5 3 Selecting the Device and Master Controller Type Chip Manager SMSC Confidential File View Options Control Help Bg EMC2102 Configurations Status Temperature Standard Format Temperature Offset Format Fan Settings Device ID Guick Help The purpose of this utility is to allow the user to view and edit SMSC device registers in the Windows environment To view a group of registers selectthe appropriate group in the left pane Ta editthe value of a register double cl
29. he hall sensor is also the TACH or Tachometer signal When the magnetic field around the Hall Sensor changes its direction the sensor s output level will follow the change to create a square wave signal as shown in Figure 6 2 Output Signal of a 2 pole Fan Assuming 2 pole fan is running at a speed of 6000 RPM it will rotate 100 revolutions per second With 2 pulses per revolution the TACH pulse signal frequency will be 200Hz Figure 6 2 Since a higher RPM will yield a higher TACH frequency or a shorter period between pulses the TACH signal can be used by the EMC devices to determine the speed of the fan Generally speaking we have TACH Pulse Frequency in HZ RPM 60 x st of Pole 1 complete fan revolution 2 pulses 5 edges Fan Tach Signal Figure 6 2 Output Signal of a 2 pole Fan EMC2102 uses a clock 32 768KHz for example to fill in a window between a programmable number of Tachometer edges A counter starts on a specific rising edge and keeps counting until it sees the set number of edges and then saves the counted pulse numbers into register 58h the TACH Reading register SMSC EMC2102 USER MANUAL Revision 0 2 09 17 07 35 Fan Speed Control with the EMC2102 Device E gt SMSE Note Although users can set the number of edges in register 52h to either 3 5 7 or 9 it is strongly recommended using the default value 5 while driving a 2 pole DC fan This equal to one complete fan revolution for a 2 pol
30. he tests in this section SMSC EMC2102 USER MANUAL Revision 0 2 09 17 07 27 Fan Speed Control with the EMC2102 Device P SMST 5 7 Experiment 7 Troubleshooting 5 7 1 Repetitious Spin up Routine Caused by Incorrect Settings At the end of spin up routine see Section 5 3 1 Fan Control Parameters the EMC2102 checks the TACH Reading register 58h If the value in this register is greater than the Valid TACH Count 56h which means the fan is running at a speed slower than the minimum valid speed the spin up routine will be restarted Figure 5 23 Fan Spin up Routine Restarted Repeatedly E Register value Hex mE Ell Fan speed RPM File Options View Control File Options Yiew Control 255 time sec 128 50 time sec Time per division SEEN Time per division pa Figure 5 23 Fan Spin up Routine Restarted Repeatedly Depending on the fan characters and EMC2102 settings there are several situations at the end of spin up routine which will be discussed Notes For ease of understanding all TACH values will be converted to RPM values in the following examples 5 7 1 1 Case 1 Spin up Lvel RPM Valid RPM Target RPM In this case the spin up level rpm rpm60 or rpm75 is smaller than both valid rpm function of 56h and target rpm function of 57h The theoretical plot of this situation is shown in Figure 5 24 Theoretical Plot of Case 1 Since the fan speed at the end of spin up routi
31. heir own configurations to CMF files through the pull down menu File gt Export Export As The CMF file used for the Experiment 1 is EMC2102 manual cmf To ensure the ChipMan application and the EMC2102 are communicating select File gt Import and then select the file emc2102 manual cmf This will import a configuration file to disable EMC2102 s RPM control function and then set a valid fan control output value The on board DC fan s speed will be reduced to about 5000 rpm at this time Select 3 Fan Settings in the ChipMan window by double clicking The window as shown in Figure 5 5 Changing Fan Speed will open Double click the last value of Fan Driver Setting register 51h and enter a new drive value should be greater than 9Ah for the on board DC fan The fan should respond and the TACH Reading register 58h should indicate an RPM reading It is recommended to set Autorefresh Registers option in ChipMan for all experiments in this user manual Select Options gt Autorefresh registers SMSC EMC2102 USER MANUAL Revision 0 2 09 17 07 11 Fan Speed Control with the EMC2102 Device P SMSE A Chip Manager SMSC Confidential File View Options Control Help uk Ss B EMCZ1 2 Register Mame Last Value Units e HWM Fan Driver Setting gw Rf Hex f 0 Configuration Status p 1 Temperature Standard Format f 2 Temperature Offset Format T 3 Fan Settings FAN Configuration RN Hex FAM Spin Up C
32. ick the value in the Last Yalue column in the right upper pane Type in the desired value The register will be updated with the new value once the cursor leaves the edit window Read only registers are denoted by R in the RAY column and editing ofthese register values is disallawaed Some registers have bitfield definitions They are displayed in the lower right pana If the register is nat read only Le read write the value of each field can be edited by double clicking on the field value in the Last Value column af this pane Type in the desired value to update the bitis of the register The field may also be changed by making a selection fram the field s drop down list If a drap down listis available for this field a combo box style button will appear atthe right ofthe Translation column Clicking the button will allow you to select a setting for the bitfield from a drop down list The current values ofthe registers can be saved to an external text file by using the Expart feature The saved text file can also be read back to the device by using the Import feature Import only affects read write registers Double click the Last value column to edit the Register or Bit value EMC2102 Found Figure 5 4 ChipMan Operation Window Revision 0 2 09 17 07 USER MANUAL SMSC EMC2102 10 Fan Speed Control with the EMC2102 Device E gt SMSE Notes 1 The EVB EMC2102 needs to be configured using the USB SMBus Bridge
33. in Figure 5 2 ChipMan Device Selection Window will appear Click on the Pull Down menu at the top select EMC2102 as shown in Figure 5 3 Selecting the Device and Master Controller Type and click OK The ChipMan operation window will then appear as shown Revision 0 2 09 17 07 USER MANUAL SMSC EMC2102 8 Fan Speed Control with the EMC2102 Device P SMSE in Figure 5 4 ChipMan Operation Window Click on the HWM icon to show the different windows available The EMC2102 WatchDog will have timed out at this point and the on board DC fan will be running at 100 Note Starting the ChipMan application without the USB cable EVB connected to the PC an error message Supported company ID on device not found will pop up Plug in the USB cable and click on Abort another pop up window will ask if you want to select an SMSC device Click on Yes and then select the device as shown in Figure 5 3 In the same device selection window the user also has the options to chose the SMBus Slave Address Default is 7A for EVB EMC2102 use Select automatically is recommended the Master Controller type Default is USB SMBus Bridge see note 1 below and if the ChipMan needs to be configured to run in simulation mode In the simulation mode users can practice the software functions without connecting a USB cable EVB to the PC For more help with ChipMan select Help gt Contents for an html based help document Select SMSC Device D
34. in Up Time 18 5 3 6 Register Change Summary 19 5 4 Experiment 4 RPM Drive Mode Rate Controls 20 5 4 1 eiie m Orm 20 5 4 2 Controlling the Ramp Rate 20 5 4 3 Register Change Summary 22 5 5 Experiment 5 Optimizing RPM Control Response 23 5 5 1 Cela D ren 23 5 5 2 Fan Configuration Register 52h 23 0 5 9 FAN Minimum Drive Register 55h and Valid TACH Count 56h 24 5 5 4 Register Change Summary 25 5 6 Experiment 6 LimitsandAlertis 26 5 6 1 General SHUPA Bde deere ears 26 5 6 2 Fan Spin and StallInterrupts 26 5 6 3 Register Change Summary 27 5 7 Experiment 7 Troubleshooting 28 5 7 1 Repetitious Spin up Routine Caused by Incorrect Settings 28 6 APP CRT rrrP 35 6 1 DC Fan Basics Poles Tach Meter PulsesandEdges 35 6 2 Characterizing a DC Fan with EVB EMC21O02andChipMan
35. ive of the response generated lil Register value Hex File Options View Control p55 2404 2104 1804 Fan Driver Setting 51h TACH Reading 58h time sec time sec Time per division 10 s Time per division 10 s Y Figure 5 9 Plots for Proper Control Settings Using this basic setup it is possible to explore how well the fan is controlled using default values Effects of Loading The EMC2102 has the ability to overcome changes in fan current requirements for a given RPM setting due to aging a blocked vent dust etc This is because the controller does not rely on absolute drive settings but rather on driving the PID loop error to O i e driving the TACH reading to equal to the TACH target To illustrate this feature simply command an RPM setting 6000 RPM for this experiment and then use a piece of paper to cover the window of the fan This will reduce the air flow through the fan and decrease the wind resistance With the same Fan Drive Setting value 240d in register 51h set by devices RPM controller less wind resistance will make the fan running faster Once the PID controller inside the EMC2102 detects the difference between the TACH reading and the TACH target 6000 RPM it will adjust the output values down to 210d in this experiment to bring the fan speed back to the target as shown in Figure 5 10 Effects of Loading Revision 0 2 09 17 07 USER MANUAL SMSC EMC2102 14
36. m Startup Speed a Stall Speed s Minimum Valid TACH Speed Maximum Fan Speed Spin up Level i e rpom60 and rpm75 Refer to Section 5 3 1 Fan Control Parameters for more details 6 2 1 General Setup s Setup the system and make sure the hardware and software are working as discussed in Section 5 1 Experiment 1 Manual Fan Control s Unplug the on board DC fan from connector P1 Connect the DC fan to be tested to P1 refer to EVB EMC2102 User Manual for the DC fan connector pinouts Revision 0 2 09 17 07 USER MANUAL SMSC EMC2102 36 Fan Speed Control with the EMC2102 Device E gt smec Verify the device is in Manual Mode 52h 7 0 6 2 2 Set the Correct LIMIT2K Value Register 52h FAN Configuration bit 6 LIMIT2K is a fan dependent parameter as discussed in Section 5 5 2 Fan Configuration Register 52h When reading the TACH Reading register 58h ChipMan uses the default LIMIT2K value 2000 rpm to convert it to an rpm speed a If the RANGE is set to 500 rpm the TACH Reading value on the ChipMan display should be multiplied by 0 5 6 2 3 Determine the Number of Poles and the Maximum Fan Speed s Set the device in Manual Mode 52h 7 0 Start the fan with 100 output drive register 51h 255h EMC2102 assumes that it is driving a 2 pole fan by default If the fan speed in register 58h does not match the fan s maximum speed specified in its datasheet then it is not a 2 pole fan The
37. me per division lis x Figure 5 33 Spin up Case 4 SMSC EMC2102 USER MANUAL Revision 0 2 09 17 07 33 Fan Speed Control with the EMC2102 Device P SMST 5 7 1 5 Case 5 Correct RPM Relationships with a Slow Response DC Fan In this case the spin up routine is too short to make the fan reach a speed higher than the valid speed Since the EMC2102 cannot detect a valid TACH at the end of spin up routine it will try to restart the fan Depending on the fan it is possible that after several spin up cycles the fan can reach the valid speed and operate normally Using the EVB EMC2102 to test this situation with rpm60 4500 rpm simply set the SPINUP TIME 53h 1 0 250 ms Valid TACH 56h 4400 rpm and start the fan with TACH Target 57h 5500 rpm Multiple spin up routines will be observed Figure 5 34 Spin up Case 5 E Register value Hex Register value Hex Legend E ll Fan speed RPM Fan speed RPM Legend xj File Options View Control Block Address Name Plot line type s Block Address Name Plot line type m HwM 51 Fan Driver Setting Ele Options View Control HWM 57 TACH Target HwM 56 Valid TACH Count 6000 HwM 58 TACH Reading 5400 4800 4200 3600 3000 2400 1800 1200 600 f 100 54 80 time sec z 054 90 time sec Time per division 4 Time per division 1 s Figure 5 34 Spin up Case 5 To fix this problem stop the fan and set the
38. n and force the fan to stop spinning This will induce a Fan Stall condition The plot of the Status Register will show a peak of 1 count for the stall condition followed by peaks of 2 counts for each time the spin up routine is invoked as shown in Figure 5 22 Fan Spin and Stall In order to see the spikes mentioned above the max scale on the register 27h plot needs to be modified To do this simply double click the 255 at the top of the Y axis type a different maximum value 10 and enter And then double click the O at the bottom of the Y axis type a minimum value and enter The scale will be changed Revision 0 2 09 17 07 USER MANUAL SMSC EMC2102 26 Fan Speed Control with the EMC2102 Device P Smsc E Register value Hex aAA EE Fan speed RPM TAR File Options View Control File Options View Control H 25 ESAE ENS H 8000 A 240 TACH TEL 57h 200 210 Fan Drive li ud 6400 li ud 1 5600 1504 4800 1204 4000 3200 904 2400 4 60 1600 30 800 time sec d time 34 80 Time per division ps Time per division ERN TACH Reading 58h Ru ze E Register value Hex EAR File Options View Control H 140 1384 1364 Interrupt Status 2 1344 23h 1324 1304 1284 1264 1244 1224 z 120 time sec 34 90 Time per division 5 s Figure 5 22 Fan Spin and Stall 5 6 3 Register Change Summary All register values are default for t
39. ne is always below the minimum valid speed a function of 56h the EMC2102 will think the fan is not running and will try to restart the fan with spin up routine over and over Using the EVB EMC2102 to test this situation with rpm60 4500 rpm simply set the Valid TACH register 56h with 4800 rpm and start the fan with TACH Target 57h 5000 rpm The repeating spin up routines can be observed Figure 5 25 Spin up Case 1 Fix 1 For rpm75 5650 rpm set 56h 6000 rpm and 57h 6500 rpm as shown in Figure 5 26 Spin up Case 1 Fix 2 There are mainly two ways to fix this problem If the spin up LEVEL in 53h is 6096 then change it to 75 as shown in Figure 5 25 Revision 0 2 09 17 07 USER MANUAL SMSC EMC2102 28 Fan Speed Control with the EMC2102 Device Fan Speed RPM RPM for 100 Drive P SMSE Wa aaa 4 Target Speed iniu an a errem Valid Speed rom60 orrpm75 Fan Speed 14 of Spin Up Time Spin Up Time Check TACH Figure 5 24 Theoretical Plot of Case 1 E Register value Hex File Options View Control HwM 51 HwM 53 time sec Register value Hex Legend xj Block Address Name Plot ine type Fan Driver Setting FAN Spin Up Configuration File om 5400 5100 4800 4500 4200 3900 3600 3300 3000 4304 20 Time per division D m lil Fan speed RPM Options View Control KI WI VAY
40. o boot up the fan In manual control open loop mode it is only invoked when starting from a 0 value in the FAN Drive Setting register 51h In the RPM control closed loop mode the spin up routine is invoked when the device is driving a stalled fan to a valid target speed i e the raw data value in register 57h TACH Target is smaller than the one in register 56h Valid TACH Count During the normal operation while the fan is running the spin up routine could also be invoked if the fan speed fell to below the valid fan speed i e the raw data value in register 58h TACH Reading is greater than the one in register 56h Valid TACH Count since the fan will be considered as stalled by the controller There are several parameters that control the fan s behavior during and after the spin up routine as shown in Figure 5 11 Fan Control Parameters When the spin up routine is operating the fan driver is set to full scale for one quarter of the total user defined spin up time For the remaining spin up time the fan driver output is set a user defined level 60 or 75 of full drive After the spin up routine has finished the RPM algorithm controls the fan speed to the TACH targets At this point if the EMC2102 cannot detect a valid fan speed the hexadecimal value in the TACH Reading register is higher than the Valid TACH Count register setting which means the fan speed is below the valid speed it will try to restart the fan Fan D
41. oltage for Ya of the time set by the SPINUP TIMET 1 0 bits in register 53h The plots in Figure 5 12 Forced Kick Function illustrate this function with a spin up time of 2 0 sec while the TACH Target register 57h is changed from 0 rpm to 5200 rpm Selecting a different Time per Division value in the pull down menu in the center bottom of the plotting window to make the 10096 kick pulse can be viewed This scale change affects both playback and real time mode The rate at which data is recorded is unaffected by changing this parameter E Register value Hex Register value Hex Legend EJ E Fan speed RPM Fan speed RPM Legend E File Options View Control Block Adtess Namo 1 Plot line type File Options View Control Block Address Name Plot line type B H Fan Driver Setting HWM 5 TACH Target HwM 58 TACH Readi f 25 eading Normal Fan Drive for 5200 rpm time sec time sec Time per division E Time per division X Figure 5 12 Forced Kick Function 5 3 4 Spin Up Level Depending on the application the value of LEVEL spin up level bit 1 in register 53h may need to be adjusted to achieve the best fan control result The plots in Figure 5 13 60 Spin Level Setting show the same experiment as Section 5 3 3 Forced Kick Function with a 60 spin up level Note the a smaller overshoot at the lower LEVEL setting SMSC EMC2102 USER MANUAL Revision 0 2 09 17 07 17 Fan Speed Control with th
42. onfiguration 53 Ry bi Hex FAM Step 54 Ru 10 Hex FAN Minimum Drive 55 RW B Hex 4 Device ID Valid TACH Count 56 RW 2010 RPM SPEOBER TACH Target 57 RAW 4510 RPM TACH Reading 58 R 4390 RPM A Bit Field Name Bitis Last value Translation Double click Ehe Last value column to edit the Register or Bit value write 4500 to offset O57 OK Figure 5 5 Changing Fan Speed 5 1 3 Plotting From ChipMan The ChipMan software has the ability to plot register values in real time up to 10Hz continuous rate To select a register to plot highlight its name or value and right click A menu with a single entry Add register to Plot will appear Figure 5 6 Plotting from the ChipMan Click the entry then a plot window should appear with a legend on top When additional registers with the same data type are selected they are added to the existing plot window In the experiment shown in Figure 5 7 Plot Windows Drive Setting TACH Target and TACH Reading were selected Note both the Tach registers are being plotted on the same graph The last step is to start the plots All plots can be started simultaneously by selecting the Control pulldown from the main application window and then Plot gt start all plots Individual plots may be paused at any time without loss of captured data on the other plot windows Chip Manager SMSC Confidential File View Options Control Help i kon T Big EMC2102 Register Name Last Isis tei Bus z Tape
43. per division 5 Figure 5 31 Spin up Routine Restarted During Normal Operation Revision 0 2 09 17 07 USER MANUAL SMSC EMC2102 32 Fan Speed Control with the EMC2102 Device P SMST 5 7 1 4 Case 4 4 Valid RPM Spin up Level RPM rpm60 or rpm75 Target RPM In this case the spin up level speed rpm60 or rpm75 is greater than the valid speed and smaller than the target speed as shown in Figure 5 32 Theoretical Plot of Case 4 At the end of spin up routine the closed loop control will drive the fan up to reach the target therefore the fan speed will never be lower than the valid speed The EMC2102 will go to the normal operation after the spin up routine Using the EVB EMC2102 to test this situation with rpm60 4500 rpm simply set the Valid TACH register 56h with 3500 rpm and start the fan with TACH Target 57h 5000 rpm Figure 5 33 Spin up Case 4 Fan Speed RPM RPM for 10096 Drive rpm60 or rpm75 Fan Speed Valid Speed Spin Up Time Check TACH Figure 5 32 Theoretical Plot of Case 4 Register value Hex Register value Hex Legend EJ E Fan speed RPM Fan speed RPM Legend E3 File Options View Control Block Address Name Plot line type z i Block Address Name Flot line type HWM 51 Fan Driver Setting File Options View Contro HWM 57 TACH Target HWM 56 Valid TACH Count HwM 58 TACH Reading c 1005530 time sec time sec Time per division 1 Ti
44. pin up time should be tailored for the fan type being used or the effect may be undesirable E Register value Hex File Options View Control time sec Time per division 500 ms lil Fan speed RPM File Options View Control time sec Time per division 500 ms X Figure 5 14 Reduced Spin up Time Revision 0 2 09 17 07 USER MANUAL SMSC EMC2102 18 Fan Speed Control with the EMC2102 Device E gt SMSE 5 3 6 Register Change Summary Table 5 2 Register Change Summary for Experiment 3 lists all register value changes from the default cmf load to accomplish the tests Table 5 2 Register Change Summary for Experiment 3 REGISTER DEFAULT NEW NAME ADDRESS VALUE VALUE COMMENT FAN Spin Up 53h Oth Oh SPINUP TIME of 2 0 sec Configuration 00000001 b 0h Change the LEVEL from 60 to 75 SMSC EMC2102 USER MANUAL Revision 0 2 09 17 07 19 Fan Speed Control with the EMC2102 Device P SMSE 5 4 Experiment 4 RPM Drive Mode Rate Controls This experiment is designed to gain familiarity with the rate control options available in the EMC2102 devices This experiment will discuss the effects of Maximum Fan Step and Update rate that can be used to control the ramp rate of a fan The two parameters ensure the fan reaches the desired drive in a reasonable time with no oscillations The CMF file for this experiment is the same as for Experiment 1 EMC1202 default cmf 5 4 1 General
45. res 3 References The following documents should be referenced when using this user manual s EMC2102 Device Datasheet s EVB EMC2102 Evaluation Board User Manual m EVB EMC2102 Evaluation Board Schematics ChipMan Software User Manual 4 The Evaluation System The evaluation system used for this user manual has two major parts as shown in Figure 4 1 EMC2102 Fan Control Evaluation System m An EMC2102 evaluation board EVB EMC2102 with on board 5V DC fan Figure 4 2 s A PC with SMSC ChipMan software installed requiring XML file for EMC2102 device This user manual contains several groups of user experiments which cover most of the fan control features of the EMC2102 fan controller device All examples are based on the 2102 device evaluation board EVB EMC2102 and its software but the methods and the results will apply to other EMC2102 applications Revision 0 2 09 17 07 USER MANUAL SMSC EMC2102 6 Fan Speed Control with the EMC2102 Device E gt Smsc d USB Connector USB Cable PC w ChipMan Software C8051F320 USB to SMBus Bridge SMBus HW Thermal EMC2102 Shutdown Configuration 28 QFN Temperature Monitoring Circuit 32 768 kHz Oscillator Figure 4 1 EMC2102 Fan Control Evaluation System 2 SYS THRM PWR ALERT pgs RE SET SUDN7 TRID T S ip ien i se ibm D4 PUE USB BRI GE ACT 1 2 1 ro ao o IP a NOT Say uja T7 l R24 Gi K t C4 nk e Lala SER GN ITP
46. rive Setting b1h Use Normal Use Spin Up Algorithm Closed loop Algorithm 100 Spin Up Level 60 75 53h 2 Fan Step 54h 5 0 Algorithm controlled drive Prev Drive Update Time Spin Up Time 52h 2 0 53h 1 0 Check TACH Target Count TACH Target Changed Reached Figure 5 11 Fan Control Parameters The spin up LEVEL 60 or 75 defined by 53h 2 has corresponding Fan Driver Setting hexadecimal values register 51h which cab be calculated using FFh as 100 and 00h as 0 For Revision 0 2 09 17 07 USER MANUAL SMSC EMC2102 16 Fan Speed Control with the EMC2102 Device E gt SMSE the 60 drive the register 51h value is 153d or 99h and for 75 it is 191d or BFh Those two drive settings will run a DC fan at two different speeds and we will call them rpm60 and rpm75 Depending on the fan the speed for the same drive setting will vary All data and plot examples in this document were taken using an EVB EMC2102 board with the on board DC fan This fan has an rpm60 of 4500 rpm and an rpm75 of 5650 rpm 5 3 2 Getting Started For all these tests the Fan Drive Setting register 51h the TACH Target register 57h and the TACH Reading registers 58h are selected to plot As bits are switched in each of the tests the register name and address will be provided 5 3 3 Forced Kick Function The EMC2102 has a forced 100 kick at turn on This feature drives the fan at maximum v
47. to work properly If in the device selection window the Master Controller type is set to I O Controller Hub then the Supported company ID on device not found message will pop up again 2 Disconnecting the USB cable and reconnecting it without restarting the ChipMan may cause register reading errors all zeros This problem can be cleared by re selecting the EMC2102 device through the device selection window Options gt Select Device 3 The SMBus Slave Address could vary depending on the device If a correct XML file is installed the ChipMan should be able to select the correct slave address automatically Refer to the device datasheet for more details about the SMBus protocol and its configurations 4 The SMSC ChipMan application allows viewing and changing register values for a variety of devices The ChipMan software only needs to be installed once to support all of these devices The list of supported devices may be found in the pulldown menu under Options gt Select Device The next step will be to load the CMF file Simply select File at the top of the window and Import from the pull down menu A pop up window will let the user to locate the right CMF Select the appropriate file and click open The CMF file will then load up the values into the EMC2102 device SMSC provides all CMF files for the operation experiments introduced in this user manual to help customers to evaluate the EMC2102 device Customers can also export t
48. tribute to personal injury or severe property damage Any and all such uses without prior written approval of an Officer of SMSC and further testing and or modification will be fully at the risk of the customer Copies of this document or other SMSC literature as well as the Terms of Sale Agreement may be obtained by visiting SMSC s website at http www smsc com SMSC is a registered trademark of Standard Microsystems Corporation SMSC Product names and company names are the trademarks of their respective holders SMSC DISCLAIMS AND EXCLUDES ANY AND ALL WARRANTIES INCLUDING WITHOUT LIMITATION ANY AND ALL IMPLIED WARRANTIES OF MERCHANTABILITY FITNESS FOR A PARTICULAR PURPOSE TITLE AND AGAINST INFRINGEMENT AND THE LIKE AND ANY AND ALL WARRANTIES ARISING FROM ANY COURSE OF DEALING OR USAGE OF TRADE IN NO EVENT SHALL SMSC BE LIABLE FOR ANY DIRECT INCIDENTAL INDIRECT SPECIAL PUNITIVE OR CONSEQUENTIAL DAMAGES OR FOR LOST DATA PROFITS SAVINGS OR REVENUES OF ANY KIND REGARDLESS OF THE FORM OF ACTION WHETHER BASED ON CONTRACT TORT NEGLIGENCE OF SMSC OR OTHERS STRICT LIABILITY BREACH OF WARRANTY OR OTHERWISE WHETHER OR NOT ANY REMEDY OF BUYER IS HELD TO HAVE FAILED OF ITS ESSENTIAL PURPOSE AND WHETHER OR NOT SMSC HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES SMSC EMC2102 USER MANUAL Revision 0 2 09 17 07 P SMSE Fan Speed Control with the EMC2102 Device Table of Contents 1 OV OR VIO 3 126393 37189 3 920 93 972
49. ts the Fan Drive Setting register 51h the TACH Target register 57h and the TACH Reading registers 58h are selected to plot As bits are switched in each of the tests the register name and address will be provided 5 5 2 Fan Configuration Register 52h The Fan Configuration Register stores the basic operation parameters of the closed loop controller The EN bit turns on the RPM controller and locks out manual updates to the Fan Drive Setting register 51h The next two parameters LIMIT2K and EDGES 1 0 both in register 52h describe the fan itself The EDGES 1 0 tell the controller how many tach edges to examine to determine the fan speed The LIMIT2K parameter tells the RPM controller how to interpret the TACH Target register 57h The value of this parameter provides an operating range for the fan by specifying the minimum rpm the 500 rpm setting is for low speed fans and the 2000 rpm setting is typical for notebook and desktop fans high speed fans Please refer to Section 6 1 DC Fan Basics Poles Tach Meter Pulses and Edges for more details about the TACH edges and ranges For all experiments in this suite the default values have been used This keeps the scaling of those values fixed allowing the ChipMan application to appropriately scale the counts to RPM values The UPDATE 2 0 parameter controls the speed at which the RPM controller updates the output drive as already been discussed in Section 5 4 Experiment 4

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