MEMS (sensors)

Posted on July 25, 2016 at 17:07Does anyone knows how the sensors sensitivity and offset changes over a big temperature difference?Application Note says:''TCSo - Sensitivity change vs. temperature: This parameter defines how sensitivitychanges with temperature. For example, at a �2.0 g full-scale range, the sensitivitychanges within �0.01%/�C. Therefore, if the environmental temperature changes40 �C, from 25 �C to 65 �C, then the sensitivity changes within the range of �0.01% * 40= �0.4%, which means the sensitivity change over 40 �C is within 0.996 mg/LSB and1.004 mg/LSB, which shows that the sensitivity is very stable versus temperaturechange. Thus, temperature compensation for sensitivity can be ignored.''Does this mean that they didn't know in which direction the Sensitivity will change if i increase the temperature by 40�C? T

Posted on July 06, 2018 at 11:51Is it possible to have several L3GD20H on the same SPI bus (running SPI mode)?The datasheet says that if chip select is high the circuit goes to I2C mode.So by selecting one chip with chip select low and the other chip selects are high, the other chips would enter I2C mode and screw up the communication?#l3gd20h

Posted on January 08, 2018 at 12:53Dear All,about this device I'm try to better understand the sensitivity parameters, from the datasheet, using the device at ±2.0g (FS bit set to 000) we must have a Sensitivity of 0.06 mg/digit, hence the number of digit should be: ±2.0/(0.06*10^-3)=±33333.3 practically I suppose ± 15 bit, I'm right?From this I try to understand the Terminology at the device datasheet page 17/58:'Sensitivity describes the gain of the sensor and can be determined, for example, byapplying 1 g acceleration to it. As the sensor can measure DC accelerations this can bedone easily by pointing the axis of interest towards the center of the Earth, noting the outputvalue, rotating the sensor by 180 degrees (pointing to the sky) and noting the output valueagain. By doing so, ±1 g acceleration is applied to the sensor. Subtracting the larger outputvalue from the smaller one, and divi

Posted on January 29, 2018 at 21:55Hi there,Is there any spec on how accurate the sample rate of the LIS3DSH accelerometer is? In our application we configure the module to sample at 1600 Hz and apply to it vibration of a known frequency. However, after performing some frequency analysis on the accelerometer output samples, the measured frequency seems to be a few Hz out from what was expected. As an example the measured frequency content would correspond to a sampling frequency of 1660 Hz, rather than 1600. However, that drift is variable from one device to the other. Is that variability something that is expected?Thank you,Stathis#lis3dsh

Posted on July 04, 2018 at 12:06I intend to use the LIS3DH as a very low power activity detector but have had no success in getting its interrupt output to behave in my application: I can make it stay always on or always off but never does it react to motion.To retain my sanity, I have gone back to the application note and written code which does exactly what the application note (section 6.3.3) says but I can't make that work either: I can see the X/Y/Z values changing but the IA bit in INT1_SRC is never set, no matter how violently I shake the chip (which is on an STEVAL-MKI105V1 board attached via I2C).  What am I doing wrong? Help!My code (in mbed-os, running on an STM32F437VG) is attached to this post, its output is below:Read I_AM_LIS3DH (0x0f): 0x33.Write CTRL_REG1 (0x20): 0x57.Write CTRL_REG2 (0x21): 0x09.Write CTRL_REG3 (0x22): 0x40.Write CTRL_RE

Posted on July 05, 2018 at 06:32Hello,We are trying to interface LIS3DSH sensor to Raspberry Pi board through I2C. Is it possible to read the data from sensor without loosing any data if we have SCLK of 100kHZ and output data rate of 1600HZ?Please suggest any possible way to achieve this(Watermark levels and Interrupts) and we need to maintain output data rate of sensor to be 1600HZ.

Posted on June 26, 2018 at 00:26Hi,I am trying to dynamically configure the interrupt threshold on the LIS2MDL. It seems that sometimes after setting a new threshold, the old threshold still is in effect and causes an interrupt transition on the output pin. Is there any minimum (settling) time required after setting a new threshold on the LIS2MDL?Thank you.

Posted on June 28, 2018 at 09:26Hello,I want to power up  LIS3DSH from my controller. The source current provided by the controller is 4mA.My device powered  from coin cell battery , so in order  to reduce the power consumption i want to de-activate all the peripherals in their non active states(power down mode also reduce my battery life).Please find the  attached image.  1)If the supply from controller the LIS3DSH need any BULK and DECAPS2)Is the CS pin take any current?3)Is any internal pull-up in the SEL pin?With Regards,Sebin Sebastian 

Posted on July 04, 2018 at 11:57Hello,I am working on a LSM6DSM. Trying to use the FIFO, I can get WaterM, OVER_RUN and FIFO_SMART_FULL in the FIFO_STATUS register. Unfortunately, I can not get these information over the interruption INT1_CTRL.Is there a procedure to activate it properly ? I can not find any information other than in the application note.Also I don't find example projects. Does anyone get guide me ?Best regards,

Posted on July 02, 2018 at 00:39Hello ST community ,I am Chayma a student of electrical engineering in national school of engineering of tunis . I am doing currently my Internship about DC motor PID regulation using STM32F407VGThe project of the internship is about PID regulation of the acceleration (position or velocity) of a DC motor using the accelerometer sensor (LIS302DL) existing in the STM32F407VGActuallay i stuck in how can i developpe a code that can do it especially the link between duty cycle and the regulated value of acceleration.I really need a quick help.thank you ,Best regards.#duty-cycle #dc-motor #accelerometer-lis302dl #stm32f4 #acceleration #stm32f407vg #pid

Posted on July 04, 2018 at 07:47Hello,We are trying to interface LIS3DSH sensor to Raspberry Pi board through I2C. Is it possible to read the data from sensor without loosing any data if we have SCLK of 100kHZ and output data rate of 1600HZ?Please suggest any possible way to achieve this(Watermark levels and Interrupts) and we need to maintain output data rate of sensor to be 1600HZ.

Posted on July 03, 2018 at 21:01We are using LIS3DSH, we are trying to read the temperature output from the sensor. however there is not much information available in the datasheet. we need to understand how often the sensor updates the temperature reading in OUT_T (0x0C) register?#lis3dsh

Posted on January 25, 2018 at 15:37Hello all,I am trying to interface SPI EEPROM, my master controller is PIC32MX575F512L, I am able to generate waveforms specified in Datasheet for READ and WRITE operations, I have also tried to read the status Register(RDSR), but all i can receive is 0xff only, kindly help me to solve this.Regards,Sunil Kumar#spi-communication #external-eeprom

Posted on July 03, 2018 at 14:18I am trying to read SPI EEPROM (M95320-DRDW8TP/K) from TI c2000 micro controller with no success. No matter whatever I do, I always receive 0xFF.HOLD and Write protection lines are tied to HIGH.Any help would be appreciated.#m95320 #c2000 #f2833x

Posted on June 28, 2018 at 17:28Hi to All !We are working on LSM6DSL based vehicle RPM Techno-meter with STM32L431KCU6 micro controller running at the speed of 80 Mhz. Our target is to read RPM by applying FFT F(max) on the single axis vibration data collected from LSM6DSL accelerometer from the range of F = 20 Hz to 200 Hz.The picture of the double layer PCB board is attached herewith for your reference.The Setting for FFT are Settings: ODR = 6000 Hz, FFT Samples = 256, Magnitude = 200mg, Full scale = +-2gFFT F(max) values received are 25Hz, 50Hz, 76Hz, 101Hz, 127Hz and not like 25,26,27,28 in continuous but getting with approximate resolution of 25Hz between two consecutive values whereas we are getting Fmax values in continuous range from one of the commercially available RPM techno-meter based on MEMS accelerometer and due to this we are unable

Posted on July 03, 2018 at 13:31Hi, I'm trying to assess the LSM6DSL built-in pedometer functionality to integrate into our product.- Has anyone experienced with it? - How accurate is it? There are several papers (e.g. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5214549/)  showing that commercial pedometers are pretty inaccurate.- Anyone knows of any commercial pedometer product based on LSM6DSL that I can try to assess the accuracy with?Thanks in advance for any lead.

Posted on July 03, 2018 at 09:31I want to detect the tilt using Renesas mcu. Please help me to develop the code

Posted on June 19, 2018 at 19:46Bluetooth Support of SPBTLE-RF (No BLE) [Bl475IOT] Hi Guys,currently I am dealing with the B-L475-IOT01A.This is equipped with a Bluetooth� V4.1 module (SPBTLE-RF).According to the data sheet (to be found in the appendix), this is a single-mode device.According to my research, no data can be sent with this chip via 'normal' Bluetooth BR / EDR.Here I would apparently have needed a dual-mode chip.Nevertheless, both BL and BLE share the layer L2CAP.The underlying physical layer is also different.BL has 79 channels, BLE has 40, different algorithms (ShiftKeying vs. Hopping) etc.Is there nevertheless the possibility to establish a communication with Bluetooth BR / EDR with the chip?

Posted on June 28, 2018 at 09:15Hi everyoneI am working with the LSM303C and with the STM32L476But LSM303c does not working at several angles.The Sensor skips values between 270 and 360 degrees.I use the prvoided library sources.Could you help me to get a perfect angle?Thank you a lot-yeo#lsm303c #mems #fft-stm32l4 #magnetometer

Posted on June 28, 2018 at 14:48I plan on using the LSM6DS3US with an SPI interface. To do this i have to set the CS line to 1. The SPI bus I have is a shared bus with SPI memory devices, each controlled by their own CS line. Therefore on first glance the LSM6DS3US should just sit on the shared bus and only become active when its CS line goes high.However...when the CS line of the LSM6DS3US is 0 it puts the SPI SDI and SCK lines into I2C mode. Therefore when I am not using the LSM6DS3US and have therefore deselected it by putting CS low, I am in fact adding an I2C device onto my shared SPI bus.This doesn't sounds good to me.Will the LSM6DS3US cope with this and will it cause issues for the other, potential active, SPI devices?#lsm6ds3us-spi-interface-(what-hapens-when-i2c-is-select

Posted on July 02, 2018 at 04:07I concerns if Machine Learning feature is inside.

Posted on June 29, 2018 at 11:58Hi Have anyone tried the full-duplex communication on BlueNRG -2 module for mobile communication? It does not detect as an audio device, it simply shows Bluetooth device. if anyone did so please guide us.Thanks in advance..!!Regards,Shyam

Posted on March 01, 2018 at 10:29Hello, I have a problem with conversion accelerometer's and magnetometer's output to pitch, roll and yaw angles. I am trying to use equations from DT0058. I wrote function like below.void newPitchRollYaw(float* const acc, float* const mag){ float roll = atan2(acc[LSM303AGR_Y], acc[LSM303AGR_Z] + acc[LSM303AGR_X] * 0.01); float pitch = atan(-acc[LSM303AGR_X] / (acc[LSM303AGR_Y] * sin(roll) + acc[LSM303AGR_Z] * cos(roll)));float By2 = mag[LSM303AGR_Z] * sin(roll) - mag[LSM303AGR_Y] * cos(roll); float Bz2 = mag[LSM303AGR_Y] * sin(roll) + mag[LSM303AGR_Z] * cos(roll); float Bx3 = mag[LSM303AGR_X] * cos(pitch) + Bz2 * sin(pitch);float yaw = atan2( By2 , Bx3); float factor = LSM303AGR_180_DEGREES / LSM303AGR_PI;log_PushLine(e_logLevel_Info, 'pitch: %f , roll: %f , yaw: %f', pitch * factor , roll * factor , yaw * factor);float Qw = cos(roll/2)*cos(

Posted on June 19, 2018 at 07:40HiI am using the accelerometer LIS2DE12 with MC60. Can you tell me how I can calculate the acceleration from the sensitivity being displayed?

Posted on February 17, 2017 at 20:28I've been trying to use the VL53L0X TOF sensor to get ranging data but I'm having trouble finding what all the registers do? I tried looking through the datasheet and API specs but nothing seemed to clearly tell me what each register is defined as. I'm coding this on a PIC24 and I don't want to use the turn-key solution provided because I don't want it to be reliant on WIN32. I'm just trying to simply set up the I2C so that it communicates with the sensor properly. If someone could tell me what registers I will need to properly get the ranging data? Or if there's a register map? Thanks.