ADXL335 3-axis Analog Accelerometer

The ADXL335 is a small, low-power, complete 3-axis MEMS accelerometer featuring signal-conditioned analog voltage outputs. Developed by Analog Devices, it measures acceleration with a minimum full-scale range of 3 g, making it a popular choice for tracking motion, detecting shock/vibration, and sensing orientation relative to gravity (tilt).Key Specifications & Features

• Measurement Range: 3 g minimum full-scale acceleration.
• Output Type: 3 independent ratiometric analog outputs (X, Y, Z axes).
• Ultra-Low Power: Draws typically 350 A of current during measurement.
• Operating Voltage: The bare IC operates between 1.8V to 3.6V. Note: Most hobbyist breakout boards (like the GY-61 or Adafruit versions) include an on-board 3.3V LDO regulator, making them 5V-ready and safe to use directly with standard microcontrollers.
• Shock Survival: Capable of surviving mechanical shocks up to 10,000 g.
• Adjustable Bandwidth: Bandwidths can be selected using external capacitors at the output pins (0.5 Hz to 1600 Hz for X/Y, and up to 550 Hz for Z).

Typical Breakout PinoutStandard 5-pin breakout modules (like the GY-61) generally share this layout:

1. VCC: Power input (typically 3V to 5V on regulated breakout boards).
2. GND: Ground connection.
3. X-OUT: Analog output voltage corresponding to acceleration along the X-axis.
4. Y-OUT: Analog output voltage corresponding to acceleration along the Y-axis.
5. Z-OUT: Analog output voltage corresponding to acceleration along the Z-axis.

How the Analog Output WorksUnlike digital alternatives that rely on protocols like IC or SPI, the ADXL335 continuously outputs raw voltage values. The output is ratiometric, meaning:

• When flat and experiencing 0 g on an axis, the voltage sits at exactly half of the supply voltage (e.g., 1.65V when powered internally at 3.3V).
• Changes in orientation or motion will dynamically scale this voltage linearly towards 0V (-3g) or 3.3V (+3g).