MEMS and sensors

I am evaluating the MotionFX library for a 9-axis orientation project. To confirm our hardware selection and production path, I have three quick questions:MCU Lock: Is the MotionFX static library (.a) restricted to STM32 microcontrollers only, or can it be linked and executed on a generic ARM Cortex-M platform?Sensor Lock: Does the algorithm require ST-branded sensors (Accel/Gyro/Mag) to function, or can it accept raw data from any 3rd party sensor?Commercial Licensing: Is there a "per-unit" royalty fee for shipping MotionFX in a commercial product, or is it royalty-free for use with STM32 silicon?We need to know if we are "locked" to the STM32 ecosystem before we begin development.

Dear STMicroelectronics Support Team,I am currently working with the A3G4250D gyroscope and evaluating its temperature sensor output over I²C.According to the datasheet, the temperature sensor output change versus temperature is specified as −1 °C per digit. I would like to clarify one point regarding the absolute digital value.At an ambient temperature of 25°C, is there a specified or typical digital output value for the OUT_TEMP register? Or is the temperature output only defined relative to an internal reference without a guaranteed absolute value at 25°C?In other words, should we expect a specific digital code at 25°C, or is the temperature register intended purely for relative temperature measurement and compensation?Your clarification would help ensure correct implementation and validation during thermal chamber testing.

I'm using a LIS3MDL magnetometer on my board, and I figured out how to calibrate it to account for distortions  caused by the board, and the procedure works. However, it seems that every time the same magnetometer is turned off and re-powered, the measurements received are different. I saw somewhere that the LIS3MDL will self calibrate at startup and I think this might be what causes the differences. Is there any way to disable this process, and if that isn't the issue, do you know what it might be?

Hi everyone,I am developing a custom board using an STM32U5 and the LSM6DSV16BX. I am using MEMS Studio to train and configure the Machine Learning Core (MLC), but I noticed that the generated .h configuration file seems to set INT1_MLC1 bit at MLC_INT1 register by default.Even though I haven't explicitly set up physical pin routing in my project, the exported C array includes bank-switching logic that forces this configuration. I see the following sequence in my generated header:  { .type = MEMS_CONF_OP_TYPE_WRITE, .address = 0x01, .data = 0x80 }, // Switch to Embedded Bank // ... [other configs] ... { .type = MEMS_CONF_OP_TYPE_WRITE, .address = 0x0D, .data = 0x01 }, // MLC_INT1: Route MLC1 to INT1 // ... [other configs] ...

Hello,I have a question about the distance values returned by the VL53L8CX across the 16 cells in 4*4 mode.I performed repeated measurement with my sensor facing the ground, both with and without a glass cover.I noticed significant discrepancies between the distance values of the different cells, even though the target is a flat ground plane.By repeating the measurements and plotting the 16 cell distances as bar graphs, I observed a consistent pattern.Graphs 1 and 2 were taken consecutively at 30 Hz.Graph 3 was taken with the sensor farther from the ground, while still facing it.    

Dear all,I'm trying to get a VD55G0 sensor (promodule connected via P-board) working on a Raspberry Pi 5. I followed the Linux Start Guide for the driver. The only difference with respect to the guide were the name of the device tree file (guide says pcb4189.dts which the repository does not contain, so I used pcb4189_vd55g0.dts), and the names of the libcamera packages (the filenames seem to have changed, I have installed both .deb packages from the STSW-IMG505_RPI download). However, the camera sensor is not detected at all:

I'd like to validate ST1VAFE3BX vAFE measurement data against test signals as part of hardware design validation of a custom ECG sensor design based on ST1VAFE3BX. I intend to input reference signals (differential or single ended) into the two bio channels of the ST1VAFE6BX, capture the raw ADC data, convert to mV, and then compare to the reference signals.- Conducting this test will help validate the data processing, especially reading and interpreting vAFE data from the FIFO, which is different than if reading from registers.Are there any documents or guides for how to do such tests?Currently the vAFE waveforms I capture look correct except for the amplitude. 

Hi, Was wondering if there is any info on when the VL53L9CX is expected to be released? Regards 

Hi Team,We have designed and manufactured several thousand PCBs that include the LIS2MDL (LGA‑12L) sensor. All boards are functioning correctly from an operational standpoint. However, because our devices run on battery power, load current is critical.We have observed a leakage current at the LIS2MDL power supply input, ranging from approximately 10 µA to 1500 µA. We are currently unable to determine whether the cause is related to the assembly process or the component itself.Notably, when we clean under IC to remove flux residues, the leakage current decreases significantly. While this confirms that contamination is influencing the issue, manually cleaning every board is not a feasible solution for our production scale.Could you please advise on possible root causes or provide recommendations to prevent this leakage issue without requiring manual cleaning for each unit?Your support would be greatly appreciated.&n

Hello guys,I am using the STEVAL-MKPRO BOX, i want to use MLC with this box. For that i tried to log data(Accelerometer data) with BLE Sensor application. The data is stored inside the micro SD . I connected the SD card to my computer and saw that  it was a .dat file. I tried to convert it into a format which is compatible with ST Mems studio with stdatalog_to_unico.py in the stdatalog-pysdk but it is not working  .I also tried using the nb_stdatalog_converters.ipynb under how_to_notebooks section but literally only the cell with conversion to unico was not working, all the other cells were working. What can i do ?Thank you in advance

Dear Sir/Madam,I am currently using a Nucleo development board to perform trials with the VL53L4CD ToF sensor.I have a question regarding the sensor’s performance in the near field range of approximately 1 to 15 cm. During testing, I positioned a matte white reference object at around 10 cm. In the data log files, I frequently observe NaN values in the measurements. However, in the GUI, a distance value is always displayed, which may possibly be interpolated.I have attached a figure from my data log showing the measurements with the reference object at approximately 10 cm.- Is this a known issue? Additionally, are there recommended methods or configuration settings to improve data quality at short distances?- What would be considered a proper or expected signal rate for this sensor? Is there a recommended range to strive for in order to ensure reliable measurements?Thank you in advance for your support.Kind regards,Jort 

Hello,we are using VL6180X and VL53L4CD sensors in an outdoor setup and we have issues with sunlight (even reflected light).To improve sunlight rejection, we added Thorlabs bandpass filters:FBH850-10 for VL6180X (850 nm)FBH940-10 for VL53L4CD (940 nm)Both filters are 2 mm thick.The filter is placed ~1 mm in front of the sensor window.We have four identical sensors per type; only one has the filter.Observations:Sensors without filter measure correctly (e.g. 143 mm → 143 mm, 70 mm → 70 mm).The sensor with the filter almost always reports a short distance (~20–30 mm).Even when the real target distance changes significantly, the filtered sensor reading remains almost constant.This looks like strong optical crosstalk rather than noise.Questions:Is a 2 mm interference filter likely to introduce severe crosstalk?

Hello,I'm using the IMP34DT05 microphone and it records fine but there is always a noise overlapped and it is very annoying.I have tried recording the background noise in anechoic chamber (see attached audio, high-pass filter alpha is 0.98). Do you know I to get rid of this noise? Is it related to microphone self-noise? Is there some processing library available from ST to remove such noise?Could it be related to some issue with the pdm2pcm conversion? I’m using 24bits on 32 frame. The PDM2PCM filter gain is set to 30.Best,

Hi I am new to the I2C communications. I am trying to communicate to the IMS330dlc chip. I am using a lab jack U3-HV.. I am programming this via Visual Studio 2022 using c# code. I cant get back the 106 for Who am I. below is the code that I setup on a push button so I could step through the code. or if anyone has example code using Visual Studio C# 2022 please send it . private void Read_AccelBtn_Click(object sender, EventArgs e) { { LJUD.IO ioType = 0; LJUD.CHANNEL channel = 0; double dblValue = 0; double dummyDouble = 0; int dummyInt = 0; double numI2CBytesToWrite; double numI2CBytesToRead; byte[] writeArray = new byte[12]; byte[] readArray = new byte[12]; long i = 0; long serialNumber = 0; double slopeDACA = 0, offsetDACA = 0, slopeDACB = 0, offsetDACB = 0; double writeACKS = 0, expectedACKS = 0; numI2CBytesToWrite = 1; writeArray[0] = 0; //Memory address. User area is 0-63. //Open the LabJack. try

Hello Team,We are using SensorTile.box Pro, and the board has been successfully flashed with the DataLogExtended.bin firmware.However, we are unable to establish a BLE connection with the board, even after flashing the DataLogExtended firmware. The device does not connect via MEMS Studio / BLE application as expected.Could you please confirm if there are:Any known issues with BLE connectivity when using Data Log Extended on SensorTile.box ProSpecific firmware versions or configuration steps required to enable BLEAny additional setup or reset procedure needed after flashingKindly advise on how to resolve this issue.Thank you for your support.Best regards,Ahilesh

Hi all, I’m confirming whether the ST LSM9DS1 provides any on-board sensor fusion output (for example quaternion/Euler), or if fusion must be done on the host MCU. If anyone has definitive guidance from ST docs/support, please share. Thanks.

Hello, I work on quality control for a company and I need to create an instruction of incoming for the item PN  LSM6DSOXTR, but I can't find any documentation about the topmarking of this item.It is mark on the item S4QR CODE504Is the "S4" the marking for  LSM6DSOXTR ?I believe that S4 is the top marking for the  LSM6DSOXTR but I need to find the oficial information that explain that. ThanksBruno M.

Dear STMicroelectronics Technical Support Team,I am currently working on reliability calculations for a design that incorporates the A3G4250D gyroscope. For accurate thermal and lifetime analysis, we require the following parameters:Maximum junction temperature (Tj max)Junction-to-ambient thermal resistance (RθJA)Junction-to-case thermal resistance (RθJC), if availableAny additional thermal characterization data relevant for reliability modelingWe have reviewed the available datasheet but were unable to locate detailed thermal resistance values necessary for our calculations.Could you please provide this information or direct us to the appropriate documentation? 

Hello.I'm working on product with LSM6DSO IMU.I have the communication working, but I'm trying to optimize a reading of the FIFO buffer.In the AN5192 document there is sentence: "The wraparound function from address FIFO_DATA_OUT_Z_H to FIFO_DATA_OUT_TAG is done automatically in the device, in order to allow reading many words with a unique multiple read operation." How should I understand this exactly? What is meant by the "unique multiple read"?I tried to read the register first using i2c write-read, and then just do simple reads of 7 bytes in a loop (for number of samples in fifo). It looks like somehow working, but I'm getting wrong data.Using the write-read for each sample works fine, but it is very inefficient. for (int i = 0; i < num; i++) { if (i == 0) { lsm6dso_read_reg(&ctx, LSM6DSO_FIFO_DATA_OUT_TAG, (uint8_t *)&sample, 7); } else {

Hi Team, I could only find the databrief and not the datasheet for VL53L1X-SATEL breakout boards. Could you provide a detailed datasheet mentioning the current consumption and power consumption at 2.8V, 3.3V and 5V respectively?I currently have a VL53L1X-SATEL breakout board for development and do you recommend the input voltage to be in 2.8V, 3.3V or 5V for this breakout board to obtain best performance from this sensor breakout board?Looking forward to your immediate and esteemed response.Best RegardsSreejith R Nair

Hi Because our recorded LG acceleration data shows strong aliasing artifacts we tried differten sensor configurations but nothing realy helped. Even worse we coud not see any effect of the LPF2 filter despide ODR and filter frequency settings. So we wunder if we have an error in our configuration or if the LPF2 not works as expected. With the following LSM configuration we expectect that the spectogram of the LG sensosr data would not show any artifacts of frequency above 250Hz.But what we see:- Frequencies below 250Hz apear as expected - Frequencies above 250Hz are folded down into the range 0-250HzWe are using the FIFO buffer to achieve constand sampling while retriving the data from the sensor with the MCU via I2C in a batch abaut 5 times per secound. For the sensor control we use the mems c-driver from gitHub (

Dear altruist, I need urgent help. Can I apply hardware-based external triggering in the VL53L8CX sensor by STM32 Nucleo F401RE? Will the sensor work for external triggering? Thank you 

Hi,I would like to confirm if setting LSM6DSO ODR to 6.66KHz and LPF2 to ODR/10 (resulting to 666Hz bandwidth), then setting a FIFO decimation factor of 8 (resulting to 833hz FIFO ODR) will work in preventing aliasing for signals above 417Hz? We have discovered with LSM6DSL that it doesn't work that well, but looking at a previous post where the LSM6DSO is recommended (Solved: LSM6DSL anti-aliasing filters do not appear to be ... - STMicroelectronics Community). So I would like to confirm it before we do a hardware change in production. Thank you. 

Hi,I'm trying to set an interupt in case of a spike, or in case of magnitue of my ISM330IS>some const - but cannot find anywhere the interupt configuration.I'm trying to get ISPU code.thanks! 

We are developing an automotive application that displays vehicle acceleration and deceleration through an LED array. We initially only utilized the accelerometer function of the ASM330LHHTR inertia module but were getting inconsistent results on inclines and declines.  We fused the 3D gyro to help compensate for this inconsistent results  but have been unsuccessful.  Is there an FAE we can speak with to help resolve our issues?