MLX90393ELW-ABA-014-SP

MLX90393 Triaxis® Magnetic Node Datasheet 1. Features and Benefits  Absolute Position Sensor IC featuring Triaxis® Hall Technology  Simple & Robust Magnetic Design  Miniature size for tiny assemblies  Selectable SPI and I2C bus protocols  Wide dynamic range (5-50mT) with on-thefly programmable gain  2.2V-3.6V supply for battery powered applications, down to 1.8V IO voltage  On board filter settings  On the fly programmable operating modes and sleep times for micro-power use  External and internal acquisition triggering modes  External interrupt pin when the field changes  On board temperature sensor 3. Description The MLX90393 brings the highest flexibility in the Triaxis portfolio's smallest packaged assembly. Additionally, the MLX90393 is designed for micropower applications, with programmable duty cycles in the range of 0.1% to 100% allowing for configurable power consumption based on system requirements. The MLX90393 magnetic field sensor can be reprogrammed to different modes and with different settings at run-time to fine-tune the performance and power consumed. The sensor offers a 16-bit output proportional to the magnetic flux density sensed along the X, Y, and Z axes using the Melexis proprietary Triaxis technology and offers a 16-bit temperature output signal. These digital values are available via I2C and SPI, where the MLX90393 is a slave on the bus. Multiple sensors can be connected to the same bus, by A0 and A1 hardwired connection (4x) but also through ordering codes with different SW address (4x). By selecting which axes are to be measured, the raw data can be used as input for further postprocessing, such as for joystick applications, rotary knobs, and more complex 3D position sensing applications. Unparalleled performance is achieved with this sensor, which is primarily targeting industrial and consumer applications. 2. Application Examples Non-contacting HMI applications with push-pull functionality    State Machine RAM Tria xis® VX VY VZ VT Control SPI/ I2C Interface ADC G EEPROM Temp Compensation Temp Sensor Home Security 3D closure detection  Accurate liquid level sensing  Factory automation position sensing  Magnetic fingerprint detection REVISION 007 – JAN 14, 2021 SDA/ MOSI SCL/ SCLK MISO MS/ CS Interrupt Trigger Oscillator Low Power Oscillator Wake-Up Joystick (gimbal or ball & socket)  3901090393 A1 Bias Rotary knobs & dials (Long stroke) Linear motion in one or two axes for levers & sliding switches A0 VDD_IO MUX  VDD Figure 1: General Block Diagram VSS MLX90393 Triaxis® Magnetic Node Datasheet Contents 1. Features and Benefits ............................................................................................................................... 1 2. Application Examples................................................................................................................................ 1 3. Description ............................................................................................................................................... 1 4. Ordering Information ............................................................................................................................... 5 5. Functional Diagram .................................................................................................................................. 6 5.1. QFN-16 Block Diagram ..................................................................................................................... 6 5.2. UTDFN-8 Block Diagram................................................................................................................... 6 6. Glossary of Terms ..................................................................................................................................... 7 7. QFN-16 Pinout .......................................................................................................................................... 8 8. UTDFN-8 Pinout ........................................................................................................................................ 9 9. Absolute Maximum Ratings .................................................................................................................... 10 10. General Electrical Specifications........................................................................................................... 11 11. Thermal Specification ........................................................................................................................... 12 12. Timing Specification ............................................................................................................................. 13 13. Magnetic Specification ......................................................................................................................... 14 13.1. Noise vs Conversion Time ............................................................................................................ 16 14. Mode Selection..................................................................................................................................... 17 14.1. Burst mode ................................................................................................................................... 18 14.2. Single Measurement mode ......................................................................................................... 18 14.3. Wake-Up on Change mode.......................................................................................................... 19 15. Digital Specification .............................................................................................................................. 19 15.1. Command List .............................................................................................................................. 20 15.2. Status Byte ................................................................................................................................... 21 15.3. SPI Communication ...................................................................................................................... 22 15.3.1. Command implementation.................................................................................................... 22 15.3.2. SPI Timing Specification ......................................................................................................... 24 15.4. I2C Communication ...................................................................................................................... 24 15.4.1. Command Implementation.................................................................................................... 25 15.4.2. I2C Timing Specification ......................................................................................................... 27 16. Memory Map ........................................................................................................................................ 28 16.1. General Description ..................................................................................................................... 28 REVISION 007 – JAN 14, 2021 3901090393 Page 2 of 43 MLX90393 Triaxis® Magnetic Node Datasheet 16.2. Parameter Description ................................................................................................................. 30 16.2.1. ANA_RESERVED_LOW............................................................................................................ 31 16.2.2. BIST ......................................................................................................................................... 31 16.2.3. Z_Series .................................................................................................................................. 31 16.2.4. GAIN_SEL[2:0] ........................................................................................................................ 32 16.2.5. HALLCONF[3:0]....................................................................................................................... 33 16.2.6. TRIG_INT_SEL ......................................................................................................................... 33 16.2.7. COMM_MODE[1:0] ................................................................................................................ 33 16.2.8. WOC_DIFF .............................................................................................................................. 33 16.2.9. EXT_TRIG ................................................................................................................................ 34 16.2.10. TCMP_EN ............................................................................................................................. 34 16.2.11. BURST_SEL[3:0] .................................................................................................................... 34 16.2.12. OSR2[1:0] ............................................................................................................................. 34 16.2.13. RES_XYZ[5:0] ........................................................................................................................ 34 16.2.14. DIG_FILT[1:0] ....................................................................................................................... 34 16.2.15. OSR[1:0] ............................................................................................................................... 34 16.2.16. SENS_TC_HT[7:0] ................................................................................................................. 34 16.2.17. SENS_TC_LT[7:0] .................................................................................................................. 35 16.2.18. OFFSET_i[15:0] ..................................................................................................................... 35 16.2.19. WOi_THRESHOLD[15:0] ....................................................................................................... 35 17. Recommended Application Diagram .................................................................................................... 36 1.1 I2C .................................................................................................................................................... 36 1.2 SPI .................................................................................................................................................... 36 18. Packaging Specification ........................................................................................................................ 37 18.1. QFN-16 ......................................................................................................................................... 37 18.1.1. Package dimensions and sensitive spot location .................................................................. 37 18.1.2. QFN-16 - Pinout and Marking ................................................................................................ 38 18.2. UDTFN-8 package......................................................................................................................... 39 18.2.1. Package dimensions and sensitive spot location .................................................................. 39 18.2.2. UTDFN-8 - Pinout and Marking.............................................................................................. 40 19. Standard Information ........................................................................................................................... 40 20. ESD Precautions.................................................................................................................................... 40 21. Revision History .................................................................................................................................... 41 REVISION 007 – JAN 14, 2021 3901090393 Page 3 of 43 MLX90393 Triaxis® Magnetic Node Datasheet 22. Contact ................................................................................................................................................. 42 23. Disclaimer ............................................................................................................................................. 43 REVISION 007 – JAN 14, 2021 3901090393 Page 4 of 43 MLX90393 Triaxis® Magnetic Node Datasheet 4. Ordering Information Product Temperature Package Option Code Packing Form Definition MLX90393 S (-20°C to 85°C) LW ABA-011 RE I2C address = 00011xx MLX90393 S (-20°C to 85°C) LW ABA-012 RE I2C address = 00100xx MLX90393 S (-20°C to 85°C) LW ABA-013 RE I2C address = 00101xx MLX90393 S (-20°C to 85°C) LW ABA-014 RE I2C address = 00110xx MLX90393 E (-40°C to 85°C) LW ABA-011 RE I2C address = 00011xx MLX90393 E (-40°C to 85°C) LW ABA-012 RE I2C address = 00100xx MLX90393 E (-40°C to 85°C) LW ABA-013 RE I2C address = 00101xx MLX90393 E (-40°C to 85°C) LW ABA-014 RE I2C address = 00110xx MLX90393 S (-20°C to 85°C) LQ ABA-011 RE I2C address = 0010000 Table 1: Product Ordering Codes Legend: Temperature Code: S: from -20°C to 85°C E: from -40°C to 85°C Package Code: “LW” for QFN-16 3x3x1mm package with wettable flanks “LQ” for UTDFN-8 2.5x2mm package Option Code: ABA-011: ABA-012: ABA-013: ABA-014: Different I2C addresses – 5 most significant bits. The 2 least significant bits of the address are defined by the external address pins A0 and A1. Packing Form: “RE for Reel” Ordering Example: “MLX90393-ELW-ABA-011-RE” MLX90393 Micropower magnetometer with I2C address 00011xx where the last two bits are defined by external address pins A0 and A1. In QFN package, temperature range -40°C to 85°C. Table 2: Product Ordering Code Example REVISION 007 – JAN 14, 2021 3901090393 Page 5 of 43 MLX90393 Triaxis® Magnetic Node Datasheet 5. Functional Diagram 5.1. QFN-16 Block Diagram 5.2. UTDFN-8 Block Diagram REVISION 007 – JAN 14, 2021 3901090393 Page 6 of 43 MLX90393 Triaxis® Magnetic Node Datasheet 6. Glossary of Terms Term Definition TC Temperature Coefficient (in ppm/°C) Gauss (G), Tesla (T) Units for the magnetic flux density − 1 mT = 10 G NC Not Connected PWM Pulse Width Modulation %DC Duty Cycle of the output signal i.e. TON /(TON + TOFF) ADC Analog-to-Digital Converter DAC Digital-to-Analog Converter LSb Least Significant Bit MSb Most Significant Bit DNL Differential Non-Linearity INL Integral Non-Linearity EMC Electro-Magnetic Compatibility REVISION 007 – JAN 14, 2021 3901090393 Page 7 of 43 MLX90393 Triaxis® Magnetic Node Datasheet 7. QFN-16 Pinout Pin Name # Type Primary Supply System Wiring Recommendation Secondary Reference To I2C 4-wire SPI 3-wire SPI Optional 1 INT I/O out N/A VDD_IO Optional Optional 2 SENB/CS I/O in MLX Test VDD_IO To VDD_IO Required Required 3 SCL/SCLK I/O in MLX Test VDD_IO Required Required Required 4 N/C -- -- -- -- -- 5 SDA/MOSI I/O bi MLX Test VDD_IO Required Required 6 MISO I/O out MLX Test VDD_IO Floating Required 7 INT/TRIG I/O bi N/A VDD_IO Optional Optional 8 VDD_IO Supply N/A Required Required Required 9 N/C -- -- -- -- -- -- 10 N/C -- -- -- -- -- -- 11 A1 I2C Address LSB MLX Test VDD To To GND VDD/GND To GND 12 A0 I2C Address LSB MLX Test VDD To To GND VDD/GND To GND 13 VSS Ground N/A 14 N/C -- -- 15 VDD Supply N/A 16 N/C -- -- -- -- -Short together Optional Required Required Required -- -- Required Required Required -- -- -- -- Table 3: Pinout Description It is recommended to connect the N/C pins (Not Connected) to Ground. REVISION 007 – JAN 14, 2021 3901090393 Page 8 of 43 MLX90393 Triaxis® Magnetic Node Datasheet 8. UTDFN-8 Pinout Pin # Name Type Primary Supply System Secondary Reference To 1 2 3 SCL/SCLK I/O in SDA/MOSI I/O bi MISO I/O out MLX Test MLX Test MLX Test VDD_IO VDD_IO VDD_IO 4 5 6 7 VDD_IO VSS VDD SENB/CS Supply Ground Supply I/O in N/A N/A N/A MLX Test VDD_IO 8 INT I/O out N/A VDD_IO Wiring Recommendation I2C 4-wire SPI 3-wire SPI Required Required Floating Required Required Required Short Required together Required Required Required To VDD_IO Optional Required Required Required Required Required Required Required Required Optional Optional Table 4: UTDFN-8 Pinout Description REVISION 007 – JAN 14, 2021 3901090393 Page 9 of 43 MLX90393 Triaxis® Magnetic Node Datasheet 9. Absolute Maximum Ratings Parameter Symbol Min. VDD_MAX Analog Supply Voltage Limits VDD_IO_MAX Typ. Max. Unit -0.3 4 V Digital IO Supply Limits -0.3 min(4, VDD+0.3) V TSTORAGE Storage (idle) temperature range -50 125 °C ESDHBM According to AEC-Q100-002 2.5 kV ESDCDM According to AEC-Q100-011-B (QFN) 750 V Table 5: Absolute Maximum Ratings Exceeding the absolute maximum ratings may cause permanent damage. conditions for extended periods may affect device reliability. REVISION 007 – JAN 14, 2021 3901090393 Exposure to absolute maximum-rated Page 10 of 43 MLX90393 Triaxis® Magnetic Node Datasheet 10. General Electrical Specifications Parameter Remark Min Nom Max Unit Analog Supply Voltage 2.2 3 3.6 V VDD_IO Digital IO Supply 1.65 1.8 VDD V VPOR_LH Power-on Reset threshold 1.42 1.55 V VDD (rising edge) VPOR_HL Power-on Reset threshold 1 1.31 V (falling edge) IDD,CONVXY Conversion Current XY-axis 2.29 3 mA IDD,CONVZ Conversion Current Z-axis 2.96 4 mA IDD,CONVT Conversion Current Temperature 1.60 2 mA Current during TCONV_END 1.5 1.75 mA 1.2 1.75 mA 1.2 1.75 mA 43 60 µA 2.4 5 µA IDD, CONV_END IDD_ACTIVE Current during TACTIVE IDD_IDLEtoSTBY Current during TSTBY IDD,STBY Standby Current(1) IDD,IDLE Idle Current(2) IDD,NOM Nominal Current (TXYZ, Datarate = 10Hz, OSR=OSR2=0, DIG_FILT=4) 1 100 µA Table 6: General Electrical Specifications 1 Standby current corresponds to the current consumed in the digital where only the low power oscillator is running. This standby current is present in burst mode, or whenever the IC is counting down to start a new conversion. 2 Idle current corresponds to the current drawn by the IC in idle mode where all operating functions are disabled except communications. REVISION 007 – JAN 14, 2021 3901090393 Page 11 of 43 MLX90393 Triaxis® Magnetic Node Datasheet 11. Thermal Specification The MLX90393 has an on-board temperature sensor which measures the temperature of the MLX90393 sensor. The temperature can be read out via the communication protocol in a digital format Parameter Symbol Min. Typ. Max. Unit TRES Temperature sensor resolution 45.2 LSB/°C T25 Temperature sensor output at 25°C 46244 LSB16u TLIN Temperature Linearity (3) +/-3 °C TOPERATING Operating temperature range [S code] -20 25 85 °C Operating temperature range [E code] -40 25 85 °C Table 7: Thermal Specifications 3 The linearity is defined as the best fit curve through the digital temperature outputs over the entire temperature range. It includes ADC non-linearity effects REVISION 007 – JAN 14, 2021 3901090393 Page 12 of 43 MLX90393 Triaxis® Magnetic Node Datasheet 12. Timing Specification The specifications are applicable at 25 Deg. C unless specified otherwise and for the complete supply range. Parameter Remark Min Nom Max Unit Main Oscillator & Derived Timings TSTBY Time from IDLE to STBY 176 220 264 µs TACTIVE Time from STBY to ACTIVE 288 360 432 µs TCONVM Single Magnetic axis conversion time(4) typical programming range 259 TCONVT Temperature conversion time typical programming range TCONV_END Time to end analog active mode TCONV_SMM Total conversion time in Single Measurement Mode 66627 𝑂𝑂𝑂𝑂𝑂𝑂 67 + 64 ∙ 2 259 80 𝐷𝐷𝐷𝐷𝐷𝐷_𝐹𝐹𝐹𝐹𝐹𝐹𝐹𝐹 ) ∙ (2 + 2 𝑂𝑂𝑂𝑂𝑂𝑂2 67 + 192 ∙ 2 100 1603 120 µs µs µs TSTBY + TACTIVE + m*TCONVM + TCONVT+ TCONV_END ms TCONV_BURST_NDLY Total conversion time in BURST with burst data rate =0 m*TCONVM + TCONVT+ TCONV_END ms TCONV_BURST_DLY Total conversion time in BURST with burst data rate > 0 TACTIVE + m*TCONVM + TCONVT+ TCONV_END ms TCONV_WOC_NDLY Total conversion time in WOC with burst data rate = 0 m*TCONVM + TCONVT+ TCONV_END ms TCONV_WOC_DLY Total conversion time in WOC with burst data rate > 0 TSTBY + TACTIVE + m*TCONVM + TCONVT+ TCONV_END ms TOSC_TRIM Trimming accuracy -5 +5 % TOSC_THD Thermal drift (full temperature range) -5 +5 % Low-power Oscillator & Derived Timings TINTERVAL TLPOSC_TRIM Time in between 2 conversions (Burst mode or Wake-Up on Change)(5) Trimming accuracy 0 1260 BURST_DATA_RATE * 20 -4 +4 ms % 4 This conversion time is defined as the time to acquire a single axis of the magnetic flux density. When measuring multiple axes they are obtained through time multiplexing. The conversion time is programmable through parameters OSR and DIG_FILT for magnetic values and OSR2 for the temperature value. The conversion sequence is TXYZ, opposite of the ZYXT argument of the command set. 5 The time TINTERVAL is defined as the time between the end of one set of measurements (any combination of TXYZ) and the start of the following same set of measurements in BURST and WOC mode. As a result of this, the maximum output data rate is not only a function of TINTERVAL but equals 1/(TCONV_BURSTWOC + TINTERVAL). REVISION 007 – JAN 14, 2021 3901090393 Page 13 of 43 MLX90393 Triaxis® Magnetic Node Datasheet Parameter TLPOSC_THD Remark Min Thermal drift (full temperature range) Nom -5 Max Unit +5 % 1.5 ms 250 us Startup TPOR Power-on-reset completion time 0.6 External Trigger TTRIG Trigger pulse width (active high) 0.01 Table 8: Timing Specifications 13. Magnetic Specification The specifications are applicable at 25 Deg. C unless otherwise specified and for the complete supply voltage range. Parameter Remark NADC ADC span NOUT Output span (taken from 19 by RESXYZ) BRANGE Min Nom Max 17.4 bits 16 bits RANGE from Table 17: Output range (function of RESXYZ) Unit mT Sensitivity table for given gain and resolution selection for HALLCONF=0xC / SENSii BSAT Magnetic saturation onset OFFS Deviation from expected 0mT output OFFSTHD Offset thermal drift, Delta from 25°C (6) SENSXX, SENSYY Programming range of magnetic resolution (µT/LSB) or sensitivity (LSB/mT) (7) [modifying GAIN_SEL and RESXYZ], cfr. Table SENSZZ 17: Sensitivity table for given gain and 50 mT 0 LSB < ±1000 LSB 3.220 0.161 µT/LSB 311 6211 LSB/mT 5.872 0.294 µT/LSB 6 The offset thermal drift is defined as the deviation at 0Gauss from the output with respect to the output at 25°C when sweeping the temperature. The highest gradient (µT/°C) typically occurs at 85°C. The spec value is based on characterization on limited sample size at GAIN_SEL=0x7 and RES_XYZ=0x00. 7 The total axis sensitivity is programmable to support different applications, but has no Automatic Gain control on-chip as do the other angular position sensors from Melexis. The highest gain corresponds to at least the minimum +/-4.8mT magnetic measurement range and the magnetic resolution defined by SENSii. REVISION 007 – JAN 14, 2021 3901090393 Page 14 of 43 MLX90393 Triaxis® Magnetic Node Datasheet Parameter Parameter Remark Min resolution selection for HALLCONF=0xC 170 Remark Min Nom Nom Max Unit 3406 LSB/mT Max Unit SENSXY, SENSYX Cross-axis sensitivity (X/Y-axis sensitivity to Y/X magnetic fields) < ±1 % SENSXZ, SENSYZ Cross-axis sensitivity (X/Y-axis sensitivity to Z magnetic field) < ±1 % SENSZX, SENSZY Cross-axis sensitivity (Z-axis sensitivity to X and Y magnetic fields) < ±1 % SENSTHD Sensitivity thermal drift -3 +3 % Delta from 25°C(8) Table 9: Magnetic Specifications 8 The sensitivity thermal drift is expressed as a band around the sensitivity at 25°C. It is applicable on wafer level trimming, but can be influenced by packaging (overmolding). REVISION 007 – JAN 14, 2021 3901090393 Page 15 of 43 MLX90393 Triaxis® Magnetic Node Datasheet 13.1. Noise vs Conversion Time The MLX90393 provides configurable filters to adjust the tradeoff between current consumption, noise, and conversion time. See section 15.1.5 for details on selecting the conversion time by adjusting OSR and DIG_FILT. XY-axis Noise over Conversion Time (bundled per OSR setting) 60 Noise Stdev [mGauss] 50 40 OSR = 0 30 OSR = 1 OSR = 2 20 OSR = 3 10 0 1 10 100 Conversion Time [ms] Figure 2: XY axis RMS noise versus conversion time, expressed in mGauss for GAIN_SEL = 0x7 Z-axis Noise over Conversion Time (bundled per OSR setting) 90 80 Noise Stdev [mGauss] 70 60 50 OSR = 0 OSR = 1 40 OSR = 2 30 OSR = 3 20 10 0 1 10 100 Conversion Time [ms] Figure 3: Z axis RMS noise versus conversion time, expressed in mGauss for GAIN_SEL = 0x7 REVISION 007 – JAN 14, 2021 3901090393 Page 16 of 43 MLX90393 Triaxis® Magnetic Node Datasheet 14. Mode Selection The MLX90393 can operate in three modes. They are: Burst mode, Single Measurement mode, and WakeOn-Change mode.  Burst mode The ASIC will have a programmable data rate at which it will operate. This data rate implies autowakeup and sequencing of the ASIC, flagging that data is ready on a dedicated pin (INT/DRDY). The maximum data rate corresponds to continuous burst mode, and is a function of the chosen measurement axes. For non-continuous burst modes, the time during which the ASIC has a counter running but is not doing an actual conversion is called the Standby mode (STBY).  Single Measure mode The master will ask for data via the corresponding protocol (I2C or SPI), waking up the ASIC to make a single conversion, immediately followed by an automatic return to sleep mode (IDLE) until the next polling of the master. This polling can also be done by strobing the TRG pin instead, which has the same effect as sending a protocol command for a single measurement.  Wake-Up on Change This mode is similar to the burst mode in the sense that the device will be auto-sequencing, with the difference that the measured component(s) is/are compared with a reference and in case the difference is bigger than a user-defined threshold, the DRDY signal is set on the designated pin. The user can select which axes and/or temperature fall under this cyclic check, and which thresholds are allowed. The user can change the operating mode at all time through a specific command on the bus. The device waits in IDLE mode after power-up, but with a proper user command any mode can be set after power-up. Changing to Burst or WOC mode, coming from Single Measure mode, is always accompanied by a measurement first. The top-level state diagram indicating the different modes and some relevant timing is shown below in Figure 4. In the Measure state, the MDATA flag will define which components will be measured (ZYXT). The order of conversion is defined as TXYZ and cannot be modified by the user, only the combination of axes is a degree of freedom. Arrows indicated in grey are the direct result of an Exit command. The main difference between STANDBY and WOC_IDLE is that in STANDBY mode, all analog circuitry is ready to make a conversion, but this is accompanied by a larger current consumption than IDLE mode. For burst mode this extra current consumption is justified because the emphasis is more on accurate timing intervals, avoiding the delay of TSTBY before conversion and supporting an efficient continuous burst mode without standby overhead. It is the user’s responsibility to read back the measured data as the MLX90393 is a slave device on the bus. Even in burst mode and WOC mode when the MLX90393 is auto-sequencing, the master will be responsible for collecting the acquired sensor data. REVISION 007 – JAN 14, 2021 3901090393 Page 17 of 43 MLX90393 Triaxis® Magnetic Node Datasheet Startup Startup Idle Command received to start measurement Enable analog Idle typ.220µs NVRAM copy typ.360µs Active Measuring WOC STBY BM STBY BM/WOC, BDR=0 WOC, BDR>0 Ending active mode typ.100µs BM, BDR>0 SM, or EX received Figure 4: Top-level state diagram with indication of timings 14.1. Burst mode When the sensor is operating in burst mode, it will make conversions at specific time intervals. The programmability of the user is the following:  Burst speed (TINTERVAL) through parameter BURST_DATA_RATE  Conversion time (TCONV) through parameters OSR, OSR2 and DIG_FILT  Axes/Temperature (MDATA) through parameter BURST_SEL or via the command argument (ZYXT) Whenever the MLX90393 has made the selected conversions (based on MDATA), the DRDY signal will be set (active H) on the INT and/or INT/TRG pin to indicate that the data is ready for readback. It will remain high until the master has sent the command to read out at least one of the converted quantities (ZYXT). Should the master have failed to read out any of them by the time the sensor has made a new conversion, the INT/DRDY pin will be strobed low for 10us, and the next rising edge will indicate a new set of data is ready. 14.2. Single Measurement mode Whenever the sensor is set to this mode (or after startup) the MLX90393 goes to the IDLE state where it awaits a command from the master to perform a certain acquisition. The duration of the acquisition will be REVISION 007 – JAN 14, 2021 3901090393 Page 18 of 43 MLX90393 Triaxis® Magnetic Node Datasheet the concatenation of the TSTBY, TACTIVE, m*TCONVM (with m # of axes) and TCONVT. The conversion time will effectively be programmable by the user (see burst mode), but is equally a function of the required axes/temperature to be measured. Upon reception of such a polling command from the master, the sensor will make the necessary acquisitions, and set the DRDY signal high to flag that the measurement has been performed and the master can read out the data on the bus at his convenience. The INT/DRDY will be cleared either when:  The master has issued a command to read out at least one of the measured components  The master issues an Exit (EX) command to cancel the measurement  The chip is reset, after POR (Power-on reset) or Reset command (RT) 14.3. Wake-Up on Change mode The Wake-Up on Change (WOC) functionality can be set by the master with as main purpose to only receive an interrupt when a certain threshold is crossed. The WOC mode will always compare a new burst value with a reference value to assess if the difference between both exceeds a user-defined threshold. The reference value is defined as one of the following:  The first measurement of WOC mode is stored as reference value once. This measurement at “t=0” is then the basis for comparison or,  The reference for acquisition(t) is always acquisition(t-1), in such a way that the INT signal will only be set if the derivative of any component exceeds a threshold. The in-application programmability is the same as for burst mode, but now the thresholds for setting the interrupt are also programmable by the user, as well as the reference, if the latter is data(t=0) or data(t-1). 15. Digital Specification The supported protocols are I2C and SPI. The SENB/CS pin is used to define the protocol to be used:  /CS = 0 for SPI, addressing the MLX90393 slave in SPI mode (3- and 4-wire), but releasing this line in between commands (no permanent addressing allowed)  /CS = 1 for I2C, addressing the MLX90393 slave when the correct address is transmitted over the bus (permanently kept high) REVISION 007 – JAN 14, 2021 3901090393 Page 19 of 43 MLX90393 Triaxis® Magnetic Node Datasheet To ensure the activity on the SPI bus cannot be accidentally interpreted as I2C protocol, programming bits are available in the memory of the MLX90393 to force the communication mode. It concerns the COMM_MODE[1:0] bits with the following effect: COMM_MODE[1] COMM_MODE[0] Description 0 X The mode in which the first valid command is transmitted to the MLX90393 defines the operating mode (SPI or I2C) for all its future commands, until a reset (hard or soft) is done. 1 0 SPI mode only 1 1 I2C mode only Table 10: Communication mode definition 15.1. Command List The MLX90393 only listens to a specific set of commands. Apart from the Reset command, all commands generate a status byte that can be read out. The table below indicates the 10 different commands that are (conditionally) accepted by the MLX90393. The MLX90393 will always acknowledge a command in I2C, even if the command is not a valid command. Interpreting the associated status byte is the method for verification of command acceptance. Command Set Command Name Symbol # CMD1 byte CMD2 byte CMD3 byte CMD4 byte Start Burst Mode SB 1 0001 zyxt N/A N/A N/A Start Wake-up on Change Mode SW 2 0010 zyxt N/A N/A N/A Start Single Measurement Mode SM 3 0011 zyxt N/A N/A N/A Read Measurement RM 4 0100 zyxt N/A N/A N/A Read Register RR 5 0101 0abc {A5…A0,0,0} N/A N/A Write Register WR 6 0110 0abc D15…D8 D7…D0 {A5…A0,0,0} Exit Mode EX 8 1000 0000 N/A N/A N/A Memory Recall HR D 1101 0000 N/A N/A N/A Memory Store HS E 1110 0000 N/A N/A N/A Reset RT F 1111 0000 N/A N/A N/A Table 11: Command List REVISION 007 – JAN 14, 2021 3901090393 Page 20 of 43 MLX90393 Triaxis® Magnetic Node Datasheet The argument for the volatile memory access commands (RR/WR) «abc» should be set to 0x0, in order to get normal read-out and write of the memory. The argument in all mode-starting commands (SB/SW/SM) is a nibble specifying the conversions to be performed by the sensor in the following order «zyxt». For example, if only Y axis and temperature are to be measured in Single Measurement mode the correct command to be transmitted is 0x35. The sequence of measurement execution on-chip is inverted to «TXYZ», so T will be measured before X, followed by Y and finally Z. By issuing an all-zero «zyxt» nibble, the BURST_SEL value from RAM will be used instead of the empty argument of the command. 15.2. Status Byte The status byte is the first byte transmitted by the MLX90393 in response to a command issued by the master. It is composed of a fixed combination of informative bits: bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 BURST_MODE WOC_MODE SM_MODE ERROR SED RS D1 D0 Table 12: Status Byte Definition  MODE bits These bits define in which mode the MLX90393 is currently set. Whenever a mode transition command is rejected, the first status byte after this command will have the expected mode bit cleared, which serves as an indication that the command has been rejected, next to the ERROR bit. The SM_MODE flag can be the result of an SM command or from raising the TRG pin when TRG mode is enabled in the volatile memory of the MLX90393.  ERROR bit This bit is set in case a command has been rejected or in case an uncorrectable error is detected in the memory, a so called ECC_ERROR. A single error in the memory can be corrected (see SED bit), two errors can be detected and will generate the ECC_ERROR. In such a case all commands but the RT (Reset) command will be rejected. The error bit is equally set when the master is reading back data while the DRDY flag is low.  SED bit The single error detection bit simply flags that a bit error in the non-volatile memory has been corrected. It is purely informative and has no impact on the operation of the MLX90393.  RS bit Whenever the MLX90393 gets out of a reset situation – both hard and soft reset – the RS flag is set to highlight this situation to the master in the first status byte that is read out. As soon as the first status byte is read, the flag is cleared until the next reset occurs.  D[1:0] bits These bits only have a meaning after the RR and RM commands, when data is expected as a response from the MLX90393. The number of response bytes correspond to 2*D[1:0] + 2, so the expected byte counts are either 2, 4, 6 or 8. For commands where no response is expected, the content of D[1:0] should be ignored. REVISION 007 – JAN 14, 2021 3901090393 Page 21 of 43 MLX90393 Triaxis® Magnetic Node Datasheet 15.3. SPI Communication The MLX90393 can handle SPI communication at a bitrate of 10Mhz. The SPI communication is implemented in a half-duplex way, showing high similarities with I2C communication, but addressing through the \CS (Chip Select) pin instead of through bus arbitration. The half-duplex nature is at the basis of the supported 3-wire SPI operation. SPI mode 3 is implemented: CPHA=1 (data changed on leading edge and captured on trailing edge, and CPOL=1 (high level is inactive state). The Chip Select line is active-low. The communication is also bundled in bytes, equally MSB first and MSByte first. A command can of course consist of more than 1 byte (refer to Table 10: Communication mode definition) as can the response be from the MLX90393 in the form of multiple bytes after the status byte (not shown in Figure 5: SPI communication example) /CS SCL 1 2 MOSI 3 4 5 6 7 8 1 3 4 5 6 7 8 X (4-wire SPI) or Z (3-wire SPI) COMMAND[7:0] MISO 2 Z (3 & 4-wire SPI) STATUS_BYTE[7:0] NADD ADD Figure 5: SPI communication example 15.3.1. Command implementation For the examples give, the below convention is used. xxx MOSI data (1 byte) xxx MISO data (1 byte) Figure 6: SPI convention 15.3.1.1. SB, SWOC, SM, EX, HR, HS All the commands follow the structure below. The reply from the MLX90393 is only the status byte. The example below is for a start of a burst mode with X and Y being measured. 0x16 0x00 xx Status Figure 7: SB command, XY After the HS command, wait at least 15ms before sending the next command to allow the IC to update the NVRAM correctly. REVISION 007 – JAN 14, 2021 3901090393 Page 22 of 43 MLX90393 Triaxis® Magnetic Node Datasheet 15.3.1.2. RT This command will (warm-)reset the IC. The status byte of the command following will indicate the reset event. It is recommended to perform an ‘EX’ command before issuing a ‘RT’ command. 0xF0 xx Figure 8: RT command 15.3.1.3. RM This command differs depending on the value for zyxt. The data is returned in the order Status-TXYZ, where the components which are set to zero are skipped. 0x4F 0x00 0x00 0x00 0x00 0x00 0x00 xx Status T [15:8] T [7:0] X [15:8] X [7:0] Y [15:8] 0x00 0x00 0x00 Y [7:0] Z [15:8] Z [7:0] Figure 9: RM command, XYZT 0x45 0x00 0x00 0x00 0x00 0x00 xx Status T [15:8] T [7:0] Y [15:8] Y [7:0] Figure 10: RM command, YT 15.3.1.4. RR Important in this command is that the register address to be read needs to be shifter left by two bits. To read register 0x12 for example, the MOSI byte becomes 0x48. 0x50 Register