Related Manuals for Infineon TLE4997
Summary of Contents for Infineon TLE4997
- Page 1 T L E 4 9 9 7 Configuration and Calibration of Linear Hall Sensor U s e r ’ s M a n u a l v01_01, 2019-08 S e n s e & C o n t r o l...
- Page 2 Infineon Technologies components may be used in life-support devices or systems only with the express written approval of Infineon Technologies, if a failure of such components can reasonably be expected to cause the failure of that life-support device or system or to affect the safety or effectiveness of that device or system. Life support devices or systems are intended to be implanted in the human body or to support and/or maintain and sustain and/or protect human life.
-
Page 3: Table Of Contents
Calibration of TLE4997 Temperature Compensation ........25... -
Page 4: Scope
User’s Manual Scope Scope This document is valid for all TLE4997 variants and derivates. It gives a detailed description of the configuration and calibration procedure, which is recommended to configure the TLE4997 for optimum accuracy in a sensing application. TLE4997 Signal Processing The TLE4997 uses a fully digital signal processing concept. -
Page 5: Tle4997 Programming
TLE4997 Programming Programmer Connection Figure 3-1 shows the connection of the TLE4997 to a programmer. The pins VDD and OUT of the sensor IC are used for the digital programming interface as described in Table 3-1 (See datasheet of corresponding TLE4997 type for pinout). -
Page 6: Programming Interface
TLE4997 User’s Manual TLE4997 Programming Programming Interface 3.2.1 Communication Scheme The digital programming interface uses specific frames, which can have one of the two following functions: • Command frames contain a specific task (e.g. read/write data, select EEPROM programming etc.) and a corresponding address •... -
Page 7: Command Frame
TLE4997 User’s Manual TLE4997 Programming In case of a wrong command or data frame, the interface is immediately locked and the device falls back to its normal application mode. The read access to the device is triggered by clock pulses on the supply line as shown Figure 3-4. -
Page 8: Data Frame
Interface Specification Table 3-3 specifies the operating conditions of the programming interface, which must be met in order to ensure correct operation of the TLE4997 during programming. All specified parameters refer to these operating conditions, unless otherwise noted. Table 3-3... - Page 9 TLE4997 User’s Manual TLE4997 Programming m in Vout init data read frame frame Figure 3-8 Frame Timing Table 3-4 Electrical and Timing Specification of the Programming Interface Parameter Symbol Values Unit Note / Test Condition Min. Typ. Max. clock high level...
- Page 10 TLE4997 User’s Manual TLE4997 Programming In order to permanently store a programmed parameter set to the EEPROM, the “EEPROM erase” and “EEPROM write” commands shall be sent, followed by a programming pulse. Figure 3-9 shows the timing of the programming pulse.
-
Page 11: Register Map
OUT erase time 79.2 80.0 80.8 PROG,ER 1) faster slope may lead to permanent damage of the EEPROM. Register Map Table 3-6 shows the internal registers of the TLE4997 (compare also Figure 2-1). Table 3-6 TLE4997 Register Map Address Symbol Function... - Page 12 TLE4997 User’s Manual TLE4997 Programming TADC This register contains a 15bit unsigned raw temperature value. STATUS The content of the status register is shown in Figure 3-11. Figure 3-11 Status Register • CRC ok has to be “1”, otherwise the DSP built-in self-test was failed and the device is defective •...
-
Page 13: Eeprom Map
Reserved Reserved - do not modify Figure 3-13 EEPROM Map of TLE4997 (all types). The fields marked in red are configuration parameters for the sensor hardware. Those marked in yellow are used by the DSP algorithms for signal processing. The purple fields are used to determine the condition of the parameters by an external programming software (user defined) and the blue and cyan fields are parity bits for the corresponding lines and columns used by the internal forward error correction (FEC). -
Page 14: Programming Flow
TLE4997 User’s Manual TLE4997 Programming User Bits The two USER bits are free bits which can be used by the system integrator, for example to track calibration steps. Lock Bits LH and LL are lock bits (LH locked if '1', LL locked if '0'). If either LH, LL or both are set to locked state, the programming interface cannot be accessed anymore. - Page 15 TLE4997 User’s Manual TLE4997 Programming EEPROM programming = 5V INIT-CMD: cmd=0x01 adr=0x0F READ DATA ILLEGAL STATUS: 0xF93D or analyse 0xFB3D ? problem CMD (write): cmd=0x09 adr=0x21 DAT: 0x0640 (DSP, FEC, REF off) CMD (b read) cmd=0x03 adc=0x10 RD. B-DATA CMD (read) >...
-
Page 16: Setting The Test Register
TLE4997 User’s Manual TLE4997 Programming 3.6.1 Setting the TEST register The following steps are used to set the TEST register: 1. Send a write command (TEST register set: Command 09 , Adress: 21 2. Send a new data word for the register. -
Page 17: Margin Voltage Check
TLE4997 User’s Manual TLE4997 Programming 3.6.6 Margin Voltage Check The threshold voltage of EEPROM cells is dependent on the programming voltage and programming pulse length. For reliable programming the programming pulse has to be kept within the specification (Table 3-5) at the sensor interface. -
Page 18: Temporary Overwrite Of Eeprom Data
TLE4997 User’s Manual TLE4997 Programming – This readout might be looped for reading out also other parameters (like TCAL) 7. Check the status register again Note: This routine can be merged with other (exemplary shown) routines. In that case only one initial frame (the very first interface access) is required after power-on. -
Page 19: Dac Setup Example
TLE4997 User’s Manual TLE4997 Programming 3.6.9 DAC setup example To find the exact DAC value for a desired output voltage (e.g. to set up the clamping low/high registers with the best available accuracy), it is possible to set the DAC value directly and to measure the result on the output pin. -
Page 20: Configuration & Calibration Parameters
To obtain a flatter output curve, it is recommended to select a higher range setting. 2) In 100 mT range, a gain value of +1.0 corresponds to typically 40mV/mT. Infineon pre-calibrates the samples to 60mV/mT.. It is recommended to do a final 2-point calibration of each IC within the application. -
Page 21: Low-Pass Filter - Lp
= 5V generally V /4095 1) Infineon pre-calibrates the samples at zero field to typically 50% output value in 100 mT range. It is recommended to do a final 2-point calibration of each IC within the application. Low-Pass Filter - LP A configurable digital low-pass filter is implemented at the output of the Hall ADC. -
Page 22: Dac Input Interpolation Filter
TLE4997 User’s Manual Configuration & Calibration Parameters Frequency (Hz) Figure 4-1 DSP Input Filter (Magnitude Plot) Table 4-5 Low-Pass Filter Parameter Symbol Values Unit Note / Test Condition Min. Typ. Max. Corner frequency variation Δ – – DAC Input Interpolation Filter An interpolation filter is placed between the DSP and the output DAC. -
Page 23: Clamping - Ch, Cl
B is mapped to voltages between 0.8 V and 4.2 V. Error range Operating range Error range B (mT) Figure 4-3 Clamping Example Clamping - TLE4997 : Table 4-6 Clamping Parameter Symbol Values Unit Note / Test Condition Min. -
Page 24: Temperature Compensation - Tl, Tq & Tt
The magnetic field strength of a magnet depends on the temperature. This material constant is specific for the different magnet types. The temperature compensation parameters TL and TQ of the TLE4997 can be adapted to compensate this temperature dependency of the magnet in the application. The TT value is fixed and cannot be modified. -
Page 25: Calibration Of Tle4997 Temperature Compensation
Initially, the TLE4997 is pre-configured by Infineon to have a constant magnetic sensitivity over temperature. In case the TLE4997 is used to measure an absolute magnetic field, for example in a current sensing application, then no additional adaption of the temperature compensation by the user is required. - Page 26 ⋅ U I ⋅ (5.5) 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 S from a sensitivity measurement over temperature, the...
-
Page 27: Determination Of Sensitivity Polynomial From Measurement
(Equation (5.3)) a measurement of the temperature behavior of the sensor output in the application is recommended. A basic example for a position sensing application using the TLE4997 and a moveable permanent magnet is shown in Figure 5-2. In a setup that uses a permanent magnet, the magnetic field has a temperature dependency due to the thermal reduction of the remanence. -
Page 28: Calculation Of Final Temperature Compensation Parameters
, it is necessary to adapt the temperature compensation paramters TL and TQ in the EEPROM such that the overall sensitivity of the TLE4997 shows the desired increase over temperature to compensate for the thermal reduction of the magnet’s remanence in the application. -
Page 29: Example Implementation Code For Temperature Calibration
TLE4997 User’s Manual Calibration of TLE4997 Temperature Compensation In a second step, the error function defined in Equation (5.10) is summed over the temperature range in finite equidistant steps T . For the computation, a step size of 10°C or less is recommended. Then, the parameters TL, TQ, and the constant C are varied until the residual ε... - Page 30 TLE4997 User’s Manual Calibration of TLE4997 Temperature Compensation Private Function epsilon(ByVal T) As Double epsilon = -1 + S_dsp(T) / (C * S_dsppre(T) * S_app(T)) End Function Iteration Loop The iteration loop looks through all TL and TQ values and check for the smallest rms error. It is done in two steps: First it looks for a rough optimum point with a coarse step size of 10 for both parameters.
- Page 31 TLE4997 User’s Manual Calibration of TLE4997 Temperature Compensation Rem --> Determine minimizing C by calculating average epsilon epsilon_sum = 0 C = 1 For T = T_min To T_max Step T_step epsilon_sum = epsilon_sum + epsilon(T) Next epsilon_mean = (epsilon_sum / n)
-
Page 32: Usage Of Infineon's Temperature Calibration Tool
(in °C) and AOUT (in V) values in the table fields marked in yellow (see Figure 5-4, upper left side). For the readout of this data, the Infineon TLE4997 Evaluation Kit can be used. 2. The tool automatically calculates the corresponding Sensitivity correction values S from the entered T... - Page 33 ( 0 to 31) final and TQ 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) [°C] Error (%) dsp,pre dsp,final dsp,pre...
-
Page 34: Calibration Of Tle4997 Output Characteristic
Pos 1 (B ~HCAL2 ~HCAL1 application movement range 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). ) HCAL ⋅ G 16384 –... -
Page 35: Two-Point Calibration Examples
Calibration with Application Readout Optimum accuracy of the TLE4997 can be achived by using a two-point calibration with readout of the HCAL registers in the application. The sensor´s output register HCAL is measured at the end points of the applications range of motion and derive the optimum offset and gain parameters from the desired VOUT values. -
Page 36: Calibration Without Application Readout
TLE4997 User’s Manual Calibration of TLE4997 Output Characteristic 6.2.2 Calibration without Application Readout In case a readout of the sensor before calibration is not desired, the sensor can be roughly calibrated just from a knowledge of the minimum and maximum magnetic flux values that occur in the application. In this case, the calibration cannot compensate any variation of parameters due to production spread of sensor IC or application module. - Page 37 2019-08 Page 35 Corrected Equation (6.3) Page 35 Corrected Equation (6.5) Page 35 Corrected offset value in the paragraph Trademarks of Infineon Technologies AG AURIX™, C166™, CanPAK™, CIPOS™, CIPURSE™, EconoPACK™, CoolMOS™, CoolSET™, CORECONTROL™, CROSSAVE™, DAVE™, DI-POL™, EasyPIM™, EconoBRIDGE™, EconoDUAL™, EconoPIM™, EconoPACK™, EiceDRIVER™, eupec™, FCOS™, HITFET™, HybridPACK™, I²RF™,...
- Page 38 . i n f i n e o n . c o m Published by Infineon Technologies AG...