The LIS2DW12TR is a MEMS (Micro-Electromechanical Systems) accelerometer manufactured by STMicroelectronics, a leading global semiconductor company. It is a 3-axis, low- Power , high-performance accelerometer designed for a wide range of applications such as motion sensing in consumer electronics, automotive, and industrial markets.
Package Type and Pinout
The LIS2DW12TR comes in a LGA (Land Grid Array) package, specifically LGA-14, which consists of 14 pins. These pins are used to connect the device to the external circuit for power, communication, and control.
Pin Function Description and Circuit Principle
The LIS2DW12TR operates with an I2C or SPI interface for communication with the host system. It features built-in low-pass filtering, high sensitivity, and is capable of detecting a wide range of acceleration from ±2g to ±16g, with the output in digital form.
Here's the complete pinout and functionality of each of the 14 pins in the LGA-14 package:
Pin Number Pin Name Pin Function Description 1 VDD Power supply input (2.4V to 3.6V). It powers the device. 2 SDA (I2C) Serial Data Line for I2C communication. It carries data to and from the Sensor in I2C mode. 3 SCL (I2C) Serial Clock Line for I2C communication. It provides the clock signal for data transfer in I2C mode. 4 CS (SPI) Chip Select pin for SPI mode. Used to select the device for SPI communication. When low, it enables the sensor's SPI interface. 5 SDI (SPI) Serial Data Input for SPI communication. It is used to send data to the device in SPI mode. 6 SDO (SPI) Serial Data Output for SPI communication. It is used to receive data from the device in SPI mode. 7 INT1 Interrupt 1 output pin. This pin can be configured to output specific interrupt signals based on the sensor's internal events. 8 INT2 Interrupt 2 output pin. Similar to INT1, this pin can be used to output other interrupt signals based on different sensor conditions. 9 GND Ground pin. It serves as the return path for current and is the reference point for the power supply. 10 VDD_IO Power supply for input/output buffers. It powers the I2C/SPI interfaces and interrupt pins. 11 RES Reserved pin, not used in the current configuration. Typically kept unconnected or used for future functions. 12 DRDY Data Ready signal. This pin is high when new data is available and low when no new data is ready to be read. 13 NC No Connection pin. It does not connect to anything internally and can be left unconnected. 14 SENS_EN Sensor Enable pin. Used to enable or disable the sensor's accelerometer functionality. When low, the sensor is in a low-power state.Circuit Principle
The LIS2DW12TR accelerometer works by converting mechanical acceleration into an electrical signal. This is achieved through a MEMS structure that includes a mass suspended by springs, which deflects when the device experiences acceleration. This deflection is sensed by capacitive plates, and the change in capacitance is used to determine the acceleration. The sensor then outputs the acceleration data in digital form using I2C or SPI communication protocols.
Pin Function FAQ (20 Common Questions)
What is the operating voltage range for the LIS2DW12TR? The LIS2DW12TR operates within a voltage range of 2.4V to 3.6V. What is the maximum current consumption of the LIS2DW12TR? The current consumption of the device depends on the operating mode, but it typically consumes around 250 µA in normal mode. How does the LIS2DW12TR communicate with a microcontroller? The device supports both I2C and SPI communication protocols. What is the function of the CS pin in SPI mode? The CS (Chip Select) pin is used to enable or disable the SPI communication with the LIS2DW12TR. It must be low to initiate communication. Can I use I2C and SPI simultaneously? No, the device can only use one communication protocol at a time, either I2C or SPI. What is the function of the DRDY pin? The DRDY pin indicates when new data is ready to be read from the device. It goes high when data is available. How can I configure the interrupt pins INT1 and INT2? The interrupt pins can be configured to output signals based on events such as threshold crossings, motion detection, or specific conditions like orientation changes. What does the RES pin do? The RES pin is reserved and typically unused in this configuration. It can be left unconnected or used for future functions. What happens if I connect the NC pin? The NC (No Connection) pin should not be connected to anything. It has no electrical function.What is the difference between VDD and VDD_IO pins?
VDD powers the internal core of the sensor, while VDD_IO powers the input/output buffers such as the I2C/SPI interface and interrupt pins.Can the sensor operate at a lower voltage than 2.4V?
No, the device requires a minimum voltage of 2.4V to operate reliably.How is data output from the LIS2DW12TR?
The sensor outputs data via the I2C or SPI interface depending on the configuration.What is the maximum data rate supported by the LIS2DW12TR?
The maximum data rate is up to 1.6kHz.Can the LIS2DW12TR detect orientation changes?
Yes, the sensor is capable of detecting changes in orientation along all three axes.What is the sensitivity range of the LIS2DW12TR?
The device has selectable sensitivity ranges of ±2g, ±4g, ±8g, and ±16g.How do I disable the LIS2DW12TR to save power?
You can disable the sensor by setting the SENS_EN pin low to put it into a low-power state.What is the significance of the INT1 and INT2 pins?
The INT1 and INT2 pins are used for outputting interrupts based on sensor events such as motion detection or threshold crossing.What happens if the sensor's supply voltage is below 2.4V?
The sensor may not operate correctly or could stop working entirely if the voltage drops below 2.4V.What happens if the SDA and SCL pins are shorted?
If the SDA (Serial Data) and SCL (Serial Clock) lines are shorted, communication will fail, and the sensor may become unresponsive.Can I use the LIS2DW12TR for tilt sensing applications?
Yes, the LIS2DW12TR is suitable for tilt sensing applications because it can detect acceleration in all three axes and determine the angle of tilt.This detailed explanation of the LIS2DW12TR provides insight into its pinout, functionality, and common questions regarding its use.
