MEMS (sensors)

I have three accelerometers and the circuit is designed according to the datasheet. I have collected the data of three kinds of accelerometers with the vibration test-bed. The sampling frequency of the accelerometers is all set to 800 Hz, placed horizontally, and the z-axis is perpendicular to the horizon. The vibration test-bed is set as the vibration frequency 50Hz, and the vibration amplitude is 0.5g. After that, I analyzed the z-axis data of the three accelerometers with FFT, and found that the noise of lsm303c is smaller than that of the other two accelerometers. Is that possible?

Hi, I am developing a device that uses the accelerometer/magnetometer LSM303AGR.The problem is that datasheet doesn´t comment about temperature sensibility (For example: Sensitivity = 16 LSB/°C in lis2dtw12)Could anyone give me an equation to convert the output temperature for the temperature registers of the LSM303AGR to Celisus Degrees?Thanks in advance

I am trying to use an acoustic scene classification from the sensing1 function pack (https://www.st.com/en/embedded-software/fp-ai-sensing1.html) that the stm32 provided for the sensortile.box. I have a difficulty integrating its sample python code model training using the stm32cube.ai. How can i generate its feature scaler.c and also its data.c for the training model code in python to be used in sensortile.box?

nRF + LIS3DH board. I need to reduce current of the nRF advertising. I want to stop the nRF advertising and use LIS3DH to trigger restarting. Can I have the LIS3DH to monitor accel data and wake up nRF when reach a threshold? I know I can have nRF connect to the LIS3DH timely through I2C to check, but the I2C is current costing, and is much more than the advertising. I am looking for a way to trigger nRF advertising by LIS3DH without using I2C. Thanks,

We have a system implemented with the development board B-L072Z-LRWAN1, now trying to reduce the size of the system. Could you help us in identifying a small size development board with similar functionality? 

Hi, I'm working with the LIS2MDL and have come across a weird issue I'm trying to resolve. My problem is that when I try to reset the chip it seems to go into a bad state. I can read and write to the same register (CFG_REG_A) just fine, but when I set the soft reset bit, I no longer get a response from the chip.Another odd thing is that when I read the CFG_REG_A register I'm reading a value of 10010011 instead of the default 00000011 even though the first thing I'm doing is reading that register. Does anyone have any ideas as to what may be going on here?Edit: Now that I've tried the same thing today, I'm not getting any response at all on MISO. I've tried with two separate chips, and getting the same results. Is there something obvious I'm missing?Thanks, Adam

Is there a tutorial or document that explains how to add the MOTIONAR library to an existing STM32CUBE IDE project? I have tried adding through STM32CUBEMX and also manually adding but I keep running into issues. When I try to manually add I get "failed to merge target specific data of file". My project used the L476, LSM6DSO and I'm using the MotionAR_CM4F_wc32_ot.a library.

Data brief mentions 178V2 compatibility to 109V2 by changing resistor settings for R2,R4,R6,R8, but nowhere can this modification info be found. What needs to be done here?

What time is needed for MP23ABS1TR is ready after power On?(The idea is to decrease MP23ABS1TR current consuption by power strobing)BR, Oleg

I would like to control the magnetometer and accelerometer calibration which occurs in the STMicro's Cube-MEMS middle ware. 1) Specifically I would like to start calibration and stop calibration so as to know when calibration occurs.2) Test the results of calibration with out added confusion due to continuous calibration during evaluation of the current calibration settings.3) To control when the Cube-MEMS EEPROM/FLASH-Store-And-Recall calibration value functions are called (used)? It would be good to know when these values are stored and / or accessed.-thanks

I need to connect X-NUCLEO-CCA02M1 with NUCLEO-401RE and I would like to use I2S. I understood that I need to use a double-clock for the I2S and a clock for the expansion board because I need to read data from rising and falling edge of the clock, but from datasheet of Microphones I read this:and the minimum clock that I can reach is 14.4 MHz (from CUBEMX) , and thus I should sent 7.2 MHz to expansion board. I can't do it.How can I solve this? I have to use HSI e LSI. I don't have HSE.In any application note that I saw, they used a I2S as master, but is it correct to use it as a slave? I could use a clock generated by a TIMx. if it is possible, how can I link a Timer to I2Sclock? Should I do it by software or is it possible do it in hardware?thank you.

I'm looking at UM2128 (en.DM00337036.pdf), "Getting started with Unicleo-GUI for motion MEMS and environmental sensor software expansion for STM32Cube", also known as "User Manual". The Revision History shows that it was updated 20-May-2019, so it should comprehend the boards I have: X-NUCLEO-IKS01A3 expansion board on a NUCLEO-L476RG. But it seems to be from another planet! The screens for the Unicleo are nothing like those I see.Then I'm studying UM2220 (en.DM00394369.pdf), "Getting started with MotionFX sensor fusion library in X-CUBE-MEMS1 expansion for STM32Cube"' also known as "User Manual". The Revision History shows that it was updated 18-Feb-2019, and that it supports the X-NUCLEO-IKS01A3 expansion board. But again, the screen shots and instructions for Unicleo operation have many details that I simply do not see when I open Unicleo.When I check out the "User Manual" for each sensor used for the fusion algorithm (UM2182, UM2181, UM2225, UM2192), I see the same thing. The examp

Hello,I have an issue with the pressure sensor LPS25HB. It looks like the LPS25HB don't work properly when the rest of the circuit drain current from the coin cell.I confirm it is a problem related to the powering of the pressure sensor LPS25HB : When the rest of the circuit uses current from the coin cell, the pressure sensor don't register correct values. If I no components drain current from the coin cell except the pressure sensor, the sensor works well and register correct values.There should be a power supply issue but I don't see any recommendation in your datasheet or AN concerning the power supply ... The sensor is powered by a coin cell (3V), it goes through a regulator and then to the LPS25HB. I also try without the regulator, the behavior stay the same.The sensor only use 30uA ... The rest of the circuit consume approx 6mA (when I see the reliability issue).The coin cell should be able to give 30uA to the pressure sensor during 10s when the rest of the system consume 6mA, n

Hello,I made a new PCB design using the LPS25HB (see PCB prints attached). On this new PCB, the LPS25HB works fine when I put a new coin cell (I get correct pressure value to compute a height difference of 50cm so I use the sensor at its maximum performance). When the Voltage on the coin cell drop a bit (below 2.9V), the sensor give wrong pressure values ... It looks like the sensor can't receive enough energy to work properly. I can say that because when I put a new coin cell, it works again. Also, if I turn on LEDS (3mA drained from the coin cell) when the pressure sensor register values, values becomes incorrect (the led drain the power I suppose).I use a regulator (MIC5232-2.8YML) between the coin cell and the pressure sensor. But I don't think the regulator is the problem because other components (accelerometer LSM6DSOX and my processor) work fine and are supplied by the regulator.I don't understand why the pressure sensor behave like that because the datasheet say that the sensor

We are using the LIS3DSH to sample acceleration data on all three axes at 800HZ. No state machine or advanced features are used. The following registers are set on initialization:CTRL_REG4 = 0x87 // 800Hz, all axes enabled CTRL_REG6 = 0x50 // fifo and watermark enabled, auto increment when doing multiple reads CTRL_REG5 = 0x08 // 4G sensingThen the FIFO_CTRL register is set to start collecting data in streaming mode:FIFO_CTRL = 0x40 //stream mode The FIFO_SRC register is read periodically and the FSS value is used to determine the number of samples in the FIFO. FSS number of samples are read out of the FIFO by doing an initial read of the Status Register at 0x27 to position the next read at OUT_X, and then reading FSS * 6 bytes to get data for all the channels using the automatic address increment feature of the sensor. In theory it seems like this should leave at least one sample in the FIFO, since FSS is “number of samples stored in the FIFO - 1�? and have no risk of reading out data

I am using MP34DT05 to calculate the A-Weighted output and for this I want to understand the sampling frequency of the sensor.

Hi, I would like to know what factory calibration procedure has been performed on this sensor and how are the calibration values used behind the scene? More specifically, there is a temperature compensation enable bit in the register map; I would like to know how it's being used and what would be the final temperature coefficient on offset with this temperature compensation used. On the datasheet, it's listed at 0.4mg/C. Is this before temp compensation or after?Another related question is on the "excellent stability over time" that's advertised on the first page of the datasheet. I could not find more details or specification on the stability. Can you provide more information from your characterization?Thanks,John

Hi, I am working on ASM330LHH IMU module. And I want to understand process or steps to get IMU alignment and calibration information.I have following queriesIMU is kept in board which can be placed in any orientation. Now, I do not know whether the X-axis of car is aligned with X-axis of IMU and same for other axes. Is there any method or process that we need to follow ? Or we have to make sure IMU orientation before using it.What is difference between IMU alignment and IMU calibration Regards,Sagar

Hi team,I use LIS3DH communicating with MCU over SPI. LIS3DH is used in current critical application. I use ST library to get access to registers. I use Low-Power mode with 1 Hz sample rate and expect to get current draw ~2uA, but instead i get ~27uA. I disabled pull-ups resistors (reg. CTRL_REG0 = 0x90). What might be the problem with current consumption?

Do you have an I2C routine that can read two byte at a time like OUT_X_L and OUT_X H or a read routine to reada all three values X<Y and Z (6 bytes) ? I am not using HAL, i am using CMSIS.

Attaching a screenshot over how it looks.Windows 10 version 1909Kind regards,Johan Dahlgren

For my project I want the LSM303AGR give me an interrupt if the read value of the X-axis falls BELOW the given threshold.For example:I have my threshold on 0.8.I bind the interrupt to to XLow and use movementrecognition.Now an interrupt is given if the x-axis goes OVER or is HIGHER than 0.8 but I want it to give an interrupt when it falls BELOW 0.8. Am I missing something or can this not be inverted?Greetings,Jaron

Hi guys.I am trying to used LIS344ALH on steval-mki109v3 with Unico GUI (v9.3.0.0).My first trial has been to connect my steval-mki109v3 with firmware V2.15.1 and Unico give me following Error message:Then I tried to connect to steval-mki109v3 after updating its firmware to V3.6.13 and results seems the same (see below).I know that into LIS344ALH documentation all refer to steval-mki109v2, but I assumed a sort of back-compatibility between two version of MEMS motherboards.Please, could someone help/clarify me that issue?Thanks in advance for your support.BRTino

I have an LSM9DS1 IMU/Magnetometer and I am having difficulty in writing a value to the control registers and reading it back after.I am using the I2C protocol with my MCU device set up as the master and the LSM9DS1 setup as the slave.1.      I am able to read correctly the WHO_AM_I and WHO_AM_I_M registers.2.      CTRL_REG1_M from the manual when reading this register is expected to return by default 0x10, when I read this register it returns 0x183.      INT_CFG_M from the manual when reading this register is expected to return by default 0x08, when I read this register it returns 0xE84.      Writing to CTRL_REG6_XL the value 0x20. When I read it back, I read 0x00.5.      Writing to CTRL_REG1_G the value 0x20. When I read it back, I read 0x00.6.      Writing to CTRL_REG3_G the value 0x80. When I read it back

First i pull both interrupt pins to GND before power up the sensor, as recommended by the datasheet. I then configure SDO pin with pull-up using register PIN_CTRL. Then i enable the accelerometer with no second filtering stage from register CTRL1_XL.I'm not sure what to configure next, and in what order to configure it, for a simple wake-up interrupt test. I assume since there is no register to put the sensor to sleep, that it defaults to sleep automatically?I do however get correct return from WHO_AM_I register, and i also can read out values from all axis.