The LIS3DSHTR is a 3-axis accelerometer manufactured by STMicroelectronics. It is part of the LIS3DH series of MEMS (Micro-Electro-Mechanical Systems) accelerometers. The LIS3DSHTR is typically used in applications such as motion sensing, tilt sensing, vibration monitoring, and other applications requiring acceleration data.
Pinout Specifications and Pin Function List:
The LIS3DSHTR comes in a LGA (Land Grid Array) package, with 16 pins. Below is a detailed explanation of each pin function and how it should be used:
Pin Number Pin Name Pin Function 1 VDD Power supply pin (positive voltage supply, typically 2.16V to 3.6V). 2 GND Ground pin. 3 SDA I2C Data pin (used for I2C communication). 4 SCL I2C Clock pin (used for I2C communication). 5 CS Chip Select pin (used in SPI communication). 6 SDI SPI Data Input pin (used in SPI communication). 7 SDO SPI Data Output pin (used in SPI communication). 8 INT1 Interrupt 1 pin. Can be configured for different interrupt functions. 9 INT2 Interrupt 2 pin. Can be configured for different interrupt functions. 10 ADDR I2C address pin (used to set the device address in I2C mode). 11 NRST Reset pin (active low, resets the device when pulled low). 12 VDDIO Supply voltage for I/O pins (usually the same as VDD). 13 VDDIO2 Supply voltage for I/O pins (optional, typically used for higher voltage I/O). 14 DRDY Data Ready pin (signals when new data is available). 15 BP Bypass pin (used for specific modes, like bypassing certain filters ). 16 VSSA Analog ground pin (typically connected to GND but can be separate for noise isolation).Full Pin Function Details:
Each pin in the table above has its specific function based on the mode of operation (SPI or I2C) and other configurations set by the user. These configurations are controlled through the device’s registers. The primary communication protocols used are I2C or SPI, and the configuration of pins like CS, SDI, SDO, SCL, and SDA depends on the chosen mode.
Circuit Principle Overview:
The LIS3DSHTR operates by measuring linear acceleration along the X, Y, and Z axes. It uses a MEMS sensor to detect changes in acceleration, which are then converted to digital values through its built-in ADC (Analog-to-Digital Converter). The sensor’s output can be read using either I2C or SPI communication. Key elements in the circuit include:
VDD (Power Supply): Supplies power to the accelerometer. GND (Ground): Provides the reference ground for the circuit. I2C/SPI Pins: Used to communicate data to/from the microcontroller. Interrupt Pins (INT1, INT2): Can be used for alerting the processor when specific events occur, such as threshold crossing or motion detection. Data Ready Pin (DRDY): This pin signals that the accelerometer data is ready to be read by the microcontroller.FAQ (Frequently Asked Questions):
Q: What is the recommended power supply voltage for the LIS3DSHTR? A: The recommended power supply voltage for the LIS3DSHTR is between 2.16V and 3.6V.
Q: How can I communicate with the LIS3DSHTR? A: You can communicate with the LIS3DSHTR using either I2C or SPI protocols. The communication mode is selected by configuring the CS pin and other relevant pins.
Q: What is the function of the CS pin in SPI mode? A: The CS (Chip Select) pin in SPI mode is used to enable or disable the communication with the LIS3DSHTR device. It must be pulled low to select the device.
Q: What is the purpose of the interrupt pins (INT1 and INT2)? A: The INT1 and INT2 pins are used to signal specific events, such as motion detection, to the microcontroller.
Q: How do I change the I2C address of the LIS3DSHTR? A: The I2C address can be configured using the ADDR pin. By setting it high or low, you can change the address of the device.
Q: Can I use the LIS3DSHTR in low-power applications? A: Yes, the LIS3DSHTR has low-power modes, such as power-down and standby modes, that help to reduce power consumption when not in use.
Q: What should I do if I need to reset the LIS3DSHTR? A: You can reset the LIS3DSHTR by pulling the NRST pin low, which will reset the device.
Q: How do I interface the LIS3DSHTR with a microcontroller? A: The LIS3DSHTR can be interfaced with a microcontroller using I2C or SPI. You will need to connect the respective data, clock, chip select, and interrupt pins.
Q: What is the function of the VDDIO pin? A: The VDDIO pin powers the I/O pins of the LIS3DSHTR and is typically connected to the same supply voltage as VDD.
Q: How do I read data from the LIS3DSHTR? A: Data can be read from the LIS3DSHTR via I2C or SPI by accessing the appropriate data registers once communication is established.
Q: What is the significance of the DRDY pin? A: The DRDY pin indicates when the data from the accelerometer is ready to be read by the host system.
Q: Can the LIS3DSHTR detect both dynamic and static acceleration? A: Yes, the LIS3DSHTR can detect both dynamic acceleration (e.g., movement) and static acceleration (e.g., gravity).
Q: What is the maximum output data rate of the LIS3DSHTR? A: The LIS3DSHTR can output data at rates up to 400 Hz, depending on the configured resolution and bandwidth.
Q: Can the LIS3DSHTR be used for vibration sensing? A: Yes, the LIS3DSHTR is suitable for vibration sensing due to its ability to measure acceleration in three axes.
Q: What kind of accelerations can the LIS3DSHTR measure? A: The LIS3DSHTR can measure accelerations in the range of ±2g, ±4g, ±8g, and ±16g, depending on the configuration.
Q: What are the power consumption modes of the LIS3DSHTR? A: The LIS3DSHTR features low-power, high-performance, and normal modes to suit different power consumption needs.
Q: How accurate is the LIS3DSHTR? A: The LIS3DSHTR offers an accuracy of about ±0.3 mg/°C for the temperature sensitivity and has a typical resolution of 12 bits.
Q: Can I use the LIS3DSHTR for tilt sensing? A: Yes, the LIS3DSHTR can be used for tilt sensing by detecting changes in acceleration due to tilting or rotating.
Q: Is the LIS3DSHTR sensitive to temperature variations? A: Yes, the LIS3DSHTR can be affected by temperature variations, but it features internal temperature compensation for improved performance.
Q: Can I use the LIS3DSHTR in automotive applications? A: Yes, the LIS3DSHTR is suitable for automotive applications, especially for in-car motion and vibration detection.
These explanations and functions provide a comprehensive guide to using the LIS3DSHTR in various applications, ensuring a clear understanding of all the pins and their functionalities.
