ADXL345 Accelerometer vs S2DW | What is ADXL345?

GY-291 ADXL345 3-axis Accelerometer Module Sensor

ADXL345

If you’re building devices like wearables, game controllers, or vibration sensors, the ADXL345 accelerometer is perfect. It precisely measures three-axis motion up to ±16g with 13-bit resolution. You can easily connect it via SPI or I²C to your MCU. Its 32-level FIFO reduces data-reading frequency, improving efficiency. Plus, features like free-fall detection and ultra-low power consumption (just 23μA) make it ideal for portable gadgets.

ADXL345 Pinout

When you’re wiring up the ADXL345, pay attention to power: VDD for main power, VDDIO matches your MCU logic. For SPI, pull CS low; for I²C, pull CS high and set SDO pin for the address (low = 0x53, high = 0x1D). Add 4.7kΩ pull-up resistors on SDA and SCL in I²C mode. INT pins are handy for interrupts like motion detection. Align carefully when soldering to avoid mix-ups.

ADXL345 Equivalent

If ADXL345 isn’t available, LIS3DH is your best bet—it matches the ±16g range and SPI/I²C interfaces, uses less power, and is smaller, perfect for wearable devices. MMA8452Q is also an option but limited to ±8g and only supports I²C. BMA280 provides better accuracy (14-bit) and lower power but has a smaller package, making hand-soldering tricky if your PCB layout is already fixed.

ADXL345 Accelerometer Circuit Example

ADXL345 Arduino

This circuit shows you how to connect an ADXL345 accelerometer with an Arduino and a 16×2 LCD. It’s perfect for beginners. Just wire VCC/GND to 5V and GND on Arduino, SDA/SCL to pins A4/A5 for I²C. Your LCD connects via pins D2–D7. Check if your ADXL345 supports 5V—if not, switch to 3.3V. Use libraries like Adafruit or SparkFun to easily read and display X, Y, Z data on the LCD.

ADXL345 Project

Here’s a simple and practical ADXL345 project for beginners: build a tilt detector using Arduino (UNO or Nano), ADXL345 accelerometer, and a 16×2 LCD. Use I²C to easily read XYZ acceleration data and display them with directions like “Tilt: RIGHT” or “Flat.” Later you can add features like vibration alarms, data logging on an SD card, Bluetooth data transmission, or even turn it into a digital level or simple pedometer—lots of fun possibilities!

ADXL345 I2C SPI Interface Tutorial

If you’re connecting ADXL345 to Arduino, STM32, or ESP32, I²C is easiest—just SDA (A4), SCL (A5), and set CS low. Address is 0x53 (SDO low) or 0x1D (SDO high). Use Arduino’s Wire library. For faster data transfer, SPI needs four pins: CS (D10), SCL (D13), SDI (D11), and SDO (D12). Always power with 3.3V—never 5V!