Sense & Control
User’s Manual
v01_01, 2019-08
TLE4997
Configuration and Calibration of Linear Hall Sensor
Page 1: ...Sense Control User s Manual v01_01 2019 08 TLE4997 Configuration and Calibration of Linear Hall Sensor ...
Page 2: ...ry terms and conditions and prices please contact the nearest Infineon Technologies Office www infineon com Warnings Due to technical requirements components may contain dangerous substances For information on the types in question please contact the nearest Infineon Technologies Office Infineon Technologies components may be used in life support devices or systems only with the express written ap...
Page 3: ...on Parameters 20 4 1 Magnetic Field Range R 20 4 2 Gain Setting G 20 4 3 Offset Setting OS 20 4 4 Low Pass Filter LP 21 4 5 DAC Input Interpolation Filter 22 4 6 Clamping CH CL 23 4 7 Temperature Compensation TL TQ TT 24 5 Calibration of TLE4997 Temperature Compensation 25 5 1 Integrated Temperature Polynomial 25 5 2 Application Sensitivity Polynomial 25 5 3 Determination of Sensitivity Polynomial...
Page 4: ... and output characteristic in the DSP and the influence of the relevant configuration parameters stored in the EEPROM The Hall signal is processed in the following sequence of steps 1 The analog Hall signal is converted by the Hall ADC which operates at the configured magnetic range setting 2 The digital value is filtered by a digital low pass filter which operates at a configurable filter frequen...
Page 5: ...the digital programming interface as described in Table 3 1 See datasheet of corresponding TLE4997 type for pinout Figure 3 1 Connection of TLE4997 to Programmer Table 3 1 Pin Functions for Programming Interface Pin Programming Function VDD Programming interface clock GND Ground OUT Programming interface data I O optional VDD I O 1 I O2 GND 47nF 47nF 47nF 47nF PROGRAMMER TLE 4997x out VDD GND TLE ...
Page 6: ...ent within 19ms after power up As an additional protection the device does not deactivate its output stage during this transmission using 21 clock pulses as shown in Figure 3 2 This means that the interface driver of the programmer needs to overrule the open drain output stage of the sensor during this initial transmission Figure 3 2 First Frame Transmission to the Sensor Attention Overruling Vout...
Page 7: ...00000 Leave programming mode1 1 not to be followed by any data frame 1H 000001 Single data readout from given address without increment sensor response one data frame 3H 000011 Data readout from given address with increment readout finishes when address xxx111B is reached 9H 001001 Single data write to given address without increment followed by one data frame BH 001011 Data write to given address...
Page 8: ...ation of the TLE4997 during programming All specified parameters refer to these operating conditions unless otherwise noted The specification for timings and electrical levels of the programming interface is shown in Table 3 4 The meaning of the timing parameters is illustrated in Figure 3 8 Table 3 3 Operating Range of the Programming Interface Parameter Symbol Values Unit Note Test Condition Min...
Page 9: ...ver especially during initial interface access to overwrite ratiometric device output VDD clock high time tCH 2 4 50 100 µs 5k 250kBit s VDD clock low time tCL 1 6 4 0 100 µs 5k 250kBit s Data in setup time tSU 1 5 2 0 µs to rising VDD Data in hold time tHLD 2 3 3 0 µs after rising VDD Data out settling time tSET 1 0 1 7 µs after rising VDD Time between frames tMIN 10 0 µs Buffer off delay tDEL 10...
Page 10: ...e value indicates a too long programming pulse duration or a too high programming voltage Table 3 5 gives the electrical and timing specifications of the programming pulse and the margin voltage check procedure Table 3 5 Electrical and Timing Specification of the Programming Pulse and Margin Voltage Parameter Symbol Values Unit Note Test Condition Min Typ Max OUT data input current IO 0 20 mA duri...
Page 11: ...ned value that corresponds to the raw Hall cell measurement value This value is in the range of 20000 OUT program slope rise 1 VO PROG t 2 V µs time to reach VO PROG shall not exceed 50 µs OUT program slope fall 1 VO PROG t 10 V µs time to reach 1v max shall not exceed 50 µs OUT write time tPROG WR 9 9 10 0 10 1 ms OUT erase time tPROG ER 79 2 80 0 80 8 ms 1 faster slope may lead to permanent dama...
Page 12: ... use ROMSIG has to be 1FH otherwise the DSP ROM is not valid and the device is defective DAC_SET This register contains a 12 bit unsigned decimal value When the DAC test bit is set the value of this register is used on the ratiometric output TEST The content of the test register is shown in Figure 3 12 All bits are 0 after reset All bits not described or used shall be kept at 0 Figure 3 12 Test Re...
Page 13: ...nal forward error correction FEC All parameters are unsigned integer values The reserved fields marked in white shall not be changed The functional description of the configuration and calibration parameters in the EEPROM map is given in Chapter 4 Parity Bits The parity Pc of each column including the precalibration ranges is even for even bit positions bit0 LSB bit2 bit4 bit14 and the parity PI f...
Page 14: ... out the EEPROM content to an array EEP_OLD store also for reference purpose and traceability In parallel Prepare the data that shall be programmed as an array EEP_NEW 5 Calculate the bits to be cleared from EEP_OLD to EEP_NEW as EEP_PROG array 6 Write the EEPROM content from the EEP_PROG array to the EEPROM registers 7 Send the EEPROM erase command Apply an erase programming pulse on the output p...
Page 15: ... CMD read cmd 0x01 adc 0x18 READ DATA CMD read cmd 0x01 adc 0x19 READ DATA 10x 16bit EEP_OLD Store this initial dataset allows later restore EEP_NEW Given by TC setup and or 2P algorithms etc User input TC setup algorithm or 2P calibration algorithm setup Create erase pattern for programming 2x 10x 16bit CMD bwrite cmd 0x0b adc 0x10 WR B DATA CMD write cmd 0x09 adc 0x18 WR DATA CMD write cmd 0x09 ...
Page 16: ...and 0BH Address 10H 2 Send the first 8 data words from the array to the EEPROM 3 Send a write command EEPROM data write Command 09H Address 18H 4 Send the 9th data word from the array to the EEPROM 5 Send a write command EEPROM data write Command 09H Address 19H 6 Send the 10th data word from the array to the EEPROM 3 6 4 Calculation of Bits to Erase The EEP_PROG array for the erase procedure is c...
Page 17: ... actual threshold voltages of each EEPROM cell can be identified by sweeping the applied VO MARG 3 6 7 DATA access example Following steps are required to readout other internal data like the calibrated temperature and Hall value as shown below in Table 3 15 This routines can also be used for an EEPROM access in that case also FECoff should be set to 1 Figure 3 15 Basic data access flow Flowchart ...
Page 18: ...tion 1 Switch on the device 2 Send an inital command status register readout 3 Read the status data check that the device is valid and the EEPROM content is valid 4 Set the test register DSP off 1 FEC off 1 REF off 1 see previous chapter 5 Send a write command for any EEPROM register Send the data words in 16bit format MSBs containing the parity may be kept 0 6 Set the test register FEC off 1 REF ...
Page 19: ...tent given by the DAC_SET register 5 Send a write command DAC_SET register Send the data word for the desired 12bit DAC value in 16bit format MSBs are 0 The output changes accordingly to the new DAC value in DAC_SET 6 After 10ms max output setup time measure Vout Repeat writing a new DAC value continue at step 5 until the response of all desired DAC values are measured 7 Check the status register ...
Page 20: ...an be calculated by 4 2 Table 4 1 Range Setting Parameter R Range Nominal Range in mT1 1 Absolute accuracy of range values is not specified 3 Low 50 12 2 Setting R 2 is not used internally changed to R 1 Mid 100 0 High 200 Table 4 2 Gain Parameter Symbol Values Unit Note Test Condition Min Typ Max Gain range Gain 4 0 3 9998 1 2 1 For Gain values between 0 5 and 0 5 the numerical accuracy decreases...
Page 21: ...OM map in Figure 3 13 Therefore the bits have to be rearranged accordingly to obtain the desired configuration For example the LP filter setting 6 corresponds to the binary 011 in the LP filter register Table 4 3 Offset Parameter Symbol Values Unit Note Test Condition Min Typ Max Offset range1 1 Infineon pre calibrates the samples at zero field to typically 50 output value in 100 mT range It is re...
Page 22: ...ter determines the frequency behavior of theTLE4997 in case the DSP input filter is disabled input filter is disabled The update rate after interpolation filter is 256 kHz Figure 4 2 DAC Input Filter Magnitude Plot Table 4 5 Low Pass Filter Parameter Symbol Values Unit Note Test Condition Min Typ Max Corner frequency variation Δf 25 25 101 10 2 10 3 0 6 5 4 3 2 1 Magnitude dB Frequency Hz 101 102 ...
Page 23: ... and Bmax is mapped to voltages between 0 8 V and 4 2 V Figure 4 3 Clamping Example Clamping TLE4997 The clamping values are calculated by Clamping low voltage 4 3 Table 4 6 Clamping Parameter Symbol Values Unit Note Test Condition Min Typ Max Clamping low1 1 If clamping is set it must be within the allowed output range VCLL 0 99 98 VDD Clamping high1 VCLH 0 99 98 VDD Clamping quantization steps Δ...
Page 24: ...n Reference temperature T0 A linear part 1st order TC1 A quadratic part 2nd order TC2 The detailed procedure to derive the optimum TL and TQ parameters for a a given magnet characteristic is described in Chapter 5 Table 4 7 Temperature Compensation Parameter Symbol Values Unit Note Test Condition Min Typ Max 1st order coefficient TC1 TC1 1000 3000 ppm C 1 1 Relative range to Infineon TC1 temperatu...
Page 25: ...tion of the TLE4997 has to be adapted to the permanent magnet employed in the application 5 1 Integrated Temperature Polynomial The integrated temperature compensation of the TLE4997 uses a third order polynomial as shown in Equation 5 1 5 1 with 5 2 TJ is the junction temperature in C The coefficients TL TQ and TT are the linear quadratic and cubic temperature compensation coefficients respective...
Page 26: ...n that relates to the junction temperature TJ by Equation 5 5 5 5 Rth is the thermal resistance of the TLE4997 as specified in the data sheet U is the supply voltage and I is the supply current After determining the application sensitivity polynomial SApp from a sensitivity measurement over temperature the sensor parameters TLfinal and TQfinal for the final sensor configuration have to be adapted ...
Page 27: ...is typically sufficient to determine a reference polynomial for the application in general which is to be used for production It is typically not required to perform the described measurement over temperature for every individual sample Figure 5 2 Example Position Sensing Application With the described setup the following procedure is used to obtain the coefficients of the application sensitivity ...
Page 28: ...hm for Finding the Optimum Temperature Coefficient Set For an optimum temperature compensation in the application the set of coefficients TL and TQ have to be found that best fulfill the condition stated in Equation 5 6 To find this parameter set an error function ε T is defined in that is minimized in an iterative procedure 5 10 SDSPfinal TJ is the integrated temperature polynomial given by the c...
Page 29: ...ial linear temperature coefficient TC2 application sensitivity polynomial quadratic temperature coefficient Valid ranges are T0_user 50 80 TC1_user 0 001 0 0025 TC2_user 0 000004 0 000004 Last but not least we have the new setup values we initialize partly TL used as sweep variable needs no initialization TQ used as sweep variable needs no initialization Valid ranges are TL 0 511 TQ 0 255 Sensitiv...
Page 30: ...to find a refined optimum Rem Initialize temperature sweep parameters T_min 40 T_max 150 T_step 10 n Math Round T_max T_min T_step Rem Initialize variables to keep track of current optimum values epsilon_rms_opt 9999 TL_opt 0 TQ_opt 0 Rem Rem Sweep in two runs the coarse global and the fine local search For Rounds 1 To 2 Rem Rem Initialize sweep parameters Rem First round coarse second round fine ...
Page 31: ... 0 For T T_min To T_max Step T_step epsilon_sum epsilon_sum epsilon T 2 Next epsilon_rms Math Sqr epsilon_sum n Rem Rem Determine if new optimum parameters were found If epsilon_rms epsilon_rms_opt Then epsilon_rms_opt epsilon_rms TL_opt TL TQ_opt TQ End If Next Next Next Rem Rem Finally retrieve the best TL TQ values stored during the sweep TL_final TL_opt TQ_final TQ_opt After the iteration is c...
Page 32: ...his data the Infineon TLE4997 Evaluation Kit can be used 5 The tool calculates the TLfinal and TQfinal parameters out of the entered TLpre and TQpre values the fixed TT value and the TC1 and TC2 coefficients determined in steps 1 3 For that an automated script is used that implements the procedure explained in Chapter 5 4 The calculated values TLfinal and TQfinal appear in the corresponding table ...
Page 33: ... VB script TLpre 166 0 to 511 TC1user 6 41E 04 C 1 TLfinal 209 TQpre 162 0 to 255 TC2user 1 59E 06 C 2 TQfinal 175 TTpre 28 0 to 31 TTfinal 28 TLpre and TQpre shall be read from the sensor via the programming interface TT is fixed by Infineon to value 28 leaded package devices or 21 SMD devices i TJ i C Sdsp pre Sapp Sdsp final Sdsp pre Sapp Error 1 40 1 0944 0 9559 1 0487 1 0462 0 24 2 20 1 0453 ...
Page 34: ...are Figure 2 1 of the Hall measurement value is evaluated at two defined positions and the output offset and gain are adjusted accordingly This procedure is illustrated in Figure 6 1 Figure 6 1 Schematic of Two Point Calibration The value VDAC is calculated in the TLE4997 with the configured offset OS and gain G value according to Equation 6 1 6 1 For the two point calibration the following proced...
Page 35: ...n be read using the TLE4997 Evaluation Kit Example An example application has a linear movement range from x1 to x2 In both positions the register value HCAL is recorded In the application it is desired to have the output value VOUT1 0 25V 5 of the full 5V range at position x1 and VOUT2 4 75V 95 of full 5V range at position x2 The measured HCAL and desired VOUT values are shown in Table 6 1 Applyi...
Page 36: ...is 50 sensor read out The 100mT default range is well suited as both magnetic flux values are well within the allowed range The sensitivity needs to be set in that way that the magnetic flux change from B2 25mT to B1 75mT results in a voltage change from Vout2 0 5V to Vout1 4 5V So the required sensitivity is Vout1 Vout2 B1 B2 4 5 0 5 75 25 0 04 V mT 40mV mT As the default sensitivity is about 60m...
Page 37: ...lectrotechnique Internationale IrDA of Infrared Data Association Corporation ISO of INTERNATIONAL ORGANIZATION FOR STANDARDIZATION MATLAB of MathWorks Inc MAXIM of Maxim Integrated Products Inc MICROTEC NUCLEUS of Mentor Graphics Corporation MIPI of MIPI Alliance Inc MIPS of MIPS Technologies Inc USA muRata of MURATA MANUFACTURING CO MICROWAVE OFFICE MWO of Applied Wave Research Inc OmniVision of ...
Page 38: ...Published by Infineon Technologies AG w w w i n f i n e o n c o m ...
