MEMS (sensors)

We embed LIS3MDLTR on our board that we produce, because this has high sensitivity: 6842 LSB/gauss. This corresponds to 0.146 mgauss/LSB, if I convert correctly. The other products has significanltly lower sensitivity: 1.5 mgauss/LSB. What are you proposing to replace the LIS3MDLTR once it is discontinued?https://www.mouser.com/PCN/STMicroelectronics_15054_1.pdfRegards

Dear ST/Forum,We are using the LPS22HBTR pressure-temperature sensor in some PCB assemblies.Due to some cleanliness requirements of the experiment, I need to be able to clean the PCB this device is attached to but due to the very fine holes in the lid to allow pressure to be measured, and your warnings in data to "not clean in solvent" etc, we are after some advice. I have purchased some liquid masking compound used in electronics assembly and propose to paint this onto the top of the device before cleaning and then peel it off after cleaning. Have you seen this done before and is it likely to cause a problem? I would prefer not to break a device trying this as replacing them on PCBs is difficult due to the geometry.The masking compound is called Techspray WonderMASK P, Peelable Solder Mask Product# 2211. Data attachedThanks in advanceDuncan

Thank you for solving my problem. Please forgive my poor English.I am using lsm6dsl sensor. When I use FIFO to read LSM6DSL, the data is correct at the beginning, but later there will be data errors. configuration :XL_ODR_208HzGY_ODR_208HzFIFO_208Hz2g, 2000dpsXL_ANA_BW_400HzLOW_NOISE_LP_ODR_DIV_100BDU EnableAfter my machine is turned on, I will run lsm6dsl_freq_reset first to ensure that my LSM6DSL is at 208Hz, but I will not turn on the FIFO. I will execute lsm6dsl_fifo_set through the serial port to turn on the FIFO. You can refer to the file I uploaded      #define PATTERN_LEN ((3 + 3 + 3) * 2) #define LSM_DATA_PACKAGE_NUM (10) void lsm6dsl_fifo_set(void) { uint8_t temp = 0xAA; lsm6dsl_int1_route_t int_1_reg;

Are there any plans to have a video tutorial on the biosensor eval board?  (ST1VAFE3BX)? I connected it to MEMS Studio via the MKI109V3.  I'm experimenting with the "Features Demo" but it's not behaving as I expect.  Perhaps there's documentation about what I should be expecting in the MEMS Studio somewhere that I'm missing? 

I am using Mems-Studio for my FSM project. I am testing the state machine, and everything is working fine; I can see interrupts. However, in the debug tab, when debug mode is enabled, the table does not compile, and I cannot observe the program's behavior. I used LSB data as shown in the examples for unico gui  

Dear ST/Forum,Preamble:We are using the LPS22HBTR pressure-temperature sensor in some PCB assemblies.The data sheet indicates a pressure reading range with defined accuracy from 260 to 1260hPA/millibar and an absolute maximum overpressure value of 2MPa (20000mbar).We are using the sensor in a vacuum application, where we expect them to not be exposed to vacuum unless there is a leak in part of the assembly. From the data sheet, we have noted there is no minimum safe pressure defined but we naturally expect the pressure readings to be at least inaccurate below 260mbar as it falls outside of the range quoted as "accurate". However we note that readings are given that seem at least sensible down to about 1mbar and then when the pressure goes lower, the sensors starts to read 4096.159874325 or similar, with the digits to the right still decreasing. Lower still and 4096 changes to 4095. We have not continued to note the readings at thes

We are currently trying to run experiments with the ILPS22QS sensor. According to the datasheet, when setting the SWRESET bit in the CTRL2 register to 1, it should self-clear when the reset is finished - but this never happens. The bit stays 1, and this also effects the official driver located at https://github.com/STMicroelectronics/STMems_Standard_C_drivers/tree/master/ilps22qs_STdC - it just runs in an infinite loop, waiting for the bit to clear.I have written my own small application to verify this.We use a Raspberry Pi as the I2C host. Does this has anything to do with it, or is the datasheet not up-to-date?

Hi, I use the ISM330DLC to measure the tilting of an excavator arm (similar to an inclinometer). I have observed that some ISM330DLC accelerometer sensors exhibit misalignment in their Z-axis measurements. For example, while the X and Y axes produce values ranging from -1000 to 1000 mg, the Z-axis measurements range from -500 to 1500 mg.To compensate for this misalignment, I apply an offset variable. However, the issue is that some sensors initially show good alignment when tested in my office, but after being installed on excavators, they develop misalignment over time, similar to what I described above.My questions are:What could be causing this misalignment to appear over time?What steps can I take to prevent this from happening?Thanks

I'm trying to add an LIS2MDL (STEVAL-MKI181V1) magnetometer to my LSM6DSV32X's (STEVAL-MKI240KA) sensor hub. I can't get the LSM6DSV32X to properly identify the LIS2MDL, and I'm not sure if it's a hardware- or firmware-related problem. My current hardware configuration is:SCx on MKI240KA tied to SCL on MKI181V1SDx on MKI240KA tied to SDA on MKI181V1INT2 on MKI240KA tied to DRDY on MKI181V1Jumpers on MKI240KA shifted to SCx/SDx positionsCS on MKI181V1 tied to VddFor context I'm using Zephyr RTOS, but the initialization sequence for the LSM6DSV32X should be the same, especially since it fails right at the beginning when attempting to identify slaves. From the LA output, it looks like the LSM6DSV32X is trying to communicate with the external sensor but it can't sufficiently drive its SCx/SDx pins?

Hello,I am writing a firmware with nrf52832 microcontroller and I have interfaced ST's LSM6DSL module. I am facing some issues regarding power consumption of LSM6DSL module. I have used 10K resistors with sda, scl, sdO and cs pins is this correct.I am initializing my module below are the commands : using the wake up interrupt with inactivity function enabled to power down gyroscope.uint32_t app_mpu_int_enable(void){uint32_t err_code;err_code = nrf_drv_mpu_write_single_register(LSM6DSL_ACC_GYRO_TAP_CFG1, 0xF0);if(err_code != NRF_SUCCESS) return err_code;err_code = nrf_drv_mpu_write_single_register(LSM6DSL_ACC_GYRO_WAKE_UP_DUR, 0x00);if(err_code != NRF_SUCCESS) return err_code;err_code = nrf_drv_mpu_write_single_register(LSM6DSL_ACC_GYRO_WAKE_UP_THS, 0x30);if(err_code != NRF_SUCCESS) return err_code;err_code = nrf_drv_mpu_write_single_register(LSM6DSL_ACC_GYRO_MD1_CFG, 0x20);if(err_code != NRF_S

Hello,my team is planning to use the gyroscope of the part LSM6DSOX in a health tracking device,and one of the engineers noticed that the readings from the Gyroscope often have measurements that go beyond ±2000dps (specified in the datasheet as Full Scale).When converting raw data to dps, based on the Angular rate sensitivity, 2000dps would correspond to around 2000dps/70mdps ≈ 28,571 (raw data). But there are raw data readings higher than 28,571.The datasheet does not cover results beyond ±2000dps.Is there any validity for readings beyond ±2000dps, to the point offor example using the given Angular rate sensitivity to convert raw data output of 32767 to ≈ 2,293dps (15% beyond Full Scale)?Or could there be any distortion involved, making readings beyond 2000dps invalid? Best Regards,

HiI managed to read both accelerometer and gyroscope ISM330DLC in "polling" mode with INT1 pin with 3330 output data rate, but my goal is to reach peak data rate (6660 samples / s) so I need to use FIFO and this is where my problems start, I dont know how to set FIFO properly, results in FIFO are intertwined. Could you show me a problem in my configuration? I have some success with enabling FIFO but I have no clue how to configure it to reach my goal which is reading acc ang gyro via primary SPI with max data rate (6660 Hz) and with lowest latency (low set fifo watermark) My code   /* Header of application modules */ #include <sensors-board-ap

HI, it seems to me that reading the LIS2MDL sensor only works correctly if I read first the X axis, then the Y axis, and finally the Z axis separately, each axis in a separate SPI transaction. My settings:- continuous measurement, output data rate set at maximum 100Hz- temperature compensation turned on- high resolution mode- low pass filter disabled, offset compensation disabled- i2c disabled, SPI 3-wire clocked 10MHz, BDU enabled- data ready interrupt on INT pin triggers enqueuing event into event queue, then main loop perform readout after some time (there are other higher priority tasks) My observations:1. Reading 8 bytes in one SPI transaction (from OUTX_L_REG 0x68 to TEMP_OUT_H_REG 0x6F)

MLC was working and suddenly stopped working , checked all the registers related to MLC and all the writes and read were happening properly.Even tested accelerometer data in the same state and it was also working fine.My device gets powered on using coin cell battery and after draining out the power , MLC started working (power dissipation in this scenario was much high than the normal scenario)

Hello everyone,I'm using the II2SDH accelerometer and want to collect the data whenever the Data Ready Interrupt is fired. I'm using the INT1 pin for that and this is my configuration: SPI_WriteByte(CTRL_REG1, 0x9f); // Low power mode, 5.376Hz data rate, XYZ Axis enable SPI_WriteByte(CTRL_REG2, 0x00); SPI_WriteByte(CTRL_REG3, 0x10); // INT1 on data ready SPI_WriteByte(CTRL_REG4, 0x00); SPI_WriteByte(CTRL_REG5, 0x00); SPI_WriteByte(CTRL_REG6, 0x00);The INT1 pin is configured as external interrupt mode on STM32, but the interrupt won't triggered. Is there any other ways to collect the data correctly? Otherwise my FFT calculation is incorrect.Any ideas how to fix the problem will be appreciated. Thanks.

I need to configure LIS3DH to generate FIFO full interrupt in INT1 pin. Once my MCU gets the hardware interrupt, it will read entire FIFO. And the loop should continue. Can anyone help me what are the correct steps to configure and read FIFO?Regards, 

I am using an adafruit stm32f405 feather, with the hal rather than arduino. I have I2c, and CDCworking now, and would like to add audio functionality with a mems mic.The I2s pins are available pins, but the clock cannot get to a low enough speed(1MHZ) through PLL.I thought about using divided master clock output ,and jumping to external source for I2s clock, but thesepins are not available. Can I use TIM3_CH2, jumped to an SPI clock input, and read the data using that periipheral.The data sheet for the mic says it can use I2s, SPI, DFSDM, and sai.  SPI is the only one that is both present, and available. I haven't seen any examples doing similar, unlike I2s cube examples. Any advice? Many thanks in advance.

I have a LIS3MDLTR connected over I2C on an aerial system that is used as part of our GNC system.  In our most recent test we received data from the magnetometer that appears to have gotten "stuck" reporting to exact same measurement (see below).  The system was flying from minute 0 until around minute 10.I've seen this behavior in the lab as well and I have found that I can temporarily fix this by rebooting the magnetometer by writing to the REBOOT bit in CTRL_REG2.  While this does resolve the issue, it frequently re-appears (about every 2-3 power ups).&nbsp

Hello,How is the INTERNAL_FREQ_FINE register set in the ISM330?Is it factory calibrated or is there on board logic that allows it change with age/temp/etc.?Thank you,Brandon M

Hello!I took two attemps and recorded measurements in steady state (2 and 3 hours) that i want share.Config:G/XL FS: default ODR 104HzSensor data polled at rate ~ 90HzSome standby/wakeup stuff:TAP_CFG0 (56h) = b0101.0001TAP_CFG2 (57h) = b1000.0000WAKE_UP_DUR (5Ch) = b0100.0000WAKE_UP_THS (5Bh) = b0000.0001MD1_CFG (5Eh) = b0010.0000Can the bias drift be explained somehow?Many thanks

Hi.I am working on evaluation with STEVAL-MKI210V2K. I use Unico to get sensor data, however what I really want is post-fusion data. Looking at other forum questions, it seems like Unico gives a "fusion" option on the left vertical tab. I don't have it (as well as the QVar option).Is it because the product I am using does not have this feature in the HW/FW level?Or am I missing something? Thanks.  

Hi,     We are use openWRT and  ism330dhcx and LIS2MDLTR  on board.  The ko driver   has been created and  insert into kernel . When read data from  /sys/devices/platform/i2c_gpio@0/i2c-0/0-006a/iio:device2/in_accel_XXXX,   We has found the Z value is random ( device dosn't move ).   it cause our heading value calculation  is not stable.   Any suggestion ?BR, arprip  Here is the log============check imu ko module =0ST imu & mag40 ko already loadedST ISM330DHCX (G sensor):accel x_raw= 804, x_scal=0.001196411accel y_raw= -18, y_scal=0.001196411accel z_raw=32764, z_scal=0.001196411check imu ko module =0ST imu & mag40 ko already loadedST ISM330DHCX (G sensor):accel x_raw= 278, x_scal=0.001196411accel y_raw= -16, y_scal=0.001196411accel z_raw= 8070, z_

Hi everyone! I am using LSM6DS3 in a very simple setup: For the debugging purposes I am only using accelerometer, ODR is set at 416Hz, fifo is enabled in continuous mode and set at the same freq, no decimation. Only XL data is set to be stored in fifo. I am reading data from fifo every second while buffer is constantly being filled. In random intervals the data I am reading gets corrupt in different ways: One axis data is simply missing (even reading the pattern confirms that there is an entry missing)Value from one axis is read out at another axis (pattern) (e.g. if device is standing still on the table, and normal reading is 10,10,-990, one of the readings can be -990,10,-990 or 10,10,10, while pattern values are always 0,1 and 2. Sometimes it even happens that the pattern is an invalid value (>2). I have tried reading values in a numerous ways (reading fifo_status 1,2,3,4 and then fifo L and fifo H) and all

Hi,  I'm trying to get the FIFO working on the LSM6DSOX on a custom board with a silicon labs microcontroller, communicating both through SPI. I have checked the application note at https://www.st.com/resource/en/application_note/an5272-lsm6dsox-alwayson-3axis-accelerometer-and-3axis-gyroscope-stmicroelectronics.pdf and followed the example code at https://github.com/STMicroelectronics/STMems_Standard_C_drivers/blob/master/lsm6dsox_STdC/examples/lsm6dsox_fifo.c, but no success, so I'm wondering if I'm missing something or it's a hardware problem. 

I am trying to read the data of the accelerometer and gyroscope of the LSM6DSV16B with an FPGA. I build a 4 wire SPI-Interface. I am able to write data to the chip and the chip is capable to give data out. But sometimes the output of the chip gets driven for a fraction of the clock cycle. This creates the spikes which you can see in the picture. Nothing other than the chip is driving the dataline. The FPGA is configured as an input and just reads the high or low state at the rising edge of the clock. As you can see in the screenshot sometimes I get a voltage spike an the data out line, sometimes the pin gets drive