MMA7361L ±1.5g, ±6g Three axis Low-G Accelerometer Module
Introduction:
MMA7361L is a Three axis Low-G accelerometer Module which gives selectable acceleration range from ±1.5g or ±6g. Board has all the necessary components required for the chip. Board made up of high quality silver plated double sided PCB for giving extra strength to the connectors.MMA7361L accelerometer has building signal conditioning, a 1-pole low pass filter, temperature compensation, self test, 0g-Detect which detects linear freefall, and g-Select which allows for the selection between 2 sensitivities. It also includes a Sleep Mode that makes it ideal for handheld battery powered electronics.Possible applications of this board includes 3D-Gaming: Tilt and Motion Sensing, Event recorder, HDD MP3 Player: Freefall Detection, Laptop PC: Freefall Detection, Anti-Theft,Cell Phone: Image Stability, Text Scroll, Motion Dialing, E-Compass, Pedometer: Motion Sensing, PDA: Text Scroll, Navigation and Dead Reckoning: E-Compass Tilt Compensation, Robotics: Motion Sensing etc.
Features
• Acceleration range along X, Y, Z axis.
• High sensitivity: 800mV/g @1.5g
• Acceleration Range: ±1.5g or ±6g
• 0g-Detect: For linear fall free protection
• Embedded Self-Test, which allows testing electrical and mechanical parts of the sensor
• Sleep mode: provides significant reduction in current
• Ratiometricity: provides system level cancellation of supply include errors in the analog
to digital conversion process.
• Environmentally preferred product.
• High shock and vibration survivability
Specification
• Supply voltage (Vdd): 2.2V to 3.6V @ 400μA
• Sleep mode current: 10 μA
• Sensitivity: 1.5g : 800 mV/g
6g : 206 mV/ g
• Static Acceleration : XOUT,YOUT,ZOUT
@ -1g : 0.85V
@ 0g : 1.65V
@ +1g: 2.45V
• Self-Test input: 0V to Vdd
• Bandwidth:
XOUT, YOUT: 400Hz
ZOUT : 300Hz
• Output Impedance : 32KΩ
Connections:
Pin Description:
XOUT: This provides the change in acceleration in X direction in terms of analog voltage
YOUT: This provides the change in acceleration in Y direction in terms of analog voltage
ZOUT: This provides the change in acceleration in Z direction in terms of analog voltage
Vss: Supply Ground: This is the supply ground pin for system.
Vdd: Supply voltage: apply the 3.3 v supply to this pin.
Sleep(Active Low): This is control input pin, logic High for normal mode where system
consume only 400μA current and logic low for Sleep mode where system consume only
10μA current.
0g-Detect: The sensor offers a 0g-Detect feature that provides a logic high signal when all
three axes are at 0g. This feature enables the application of Linear Freefall protection if the
signal is connected to an interrupt pin or a poled I/O pin on a microcontroller.
G-select: The G-Select feature allows for the selection between two sensitivities.
Depending on the logic input placed on this pin, the device internal gain will be changed
allowing it to function with a 1.5g or 6g sensitivity.
ST(Self-test): Self Test allows the verification of the mechanical and electrical integrity of
the accelerometer at any time before or after installation.
To use this feature to verify the 0g-Detect function, the accelerometer should be held upside
down so that the z-axis experiences -1g. When the self test function is initiated, an
electrostatic force is applied to each axis to cause it to deflect. The x- and y-axis are deflected
slightly while the z-axis is trimmed to deflect 1g. This procedure assures that both the
mechanical (g-cell) and electronic sections of the accelerometer are functioning. To test Self
Test function apply logic 1 to the pin. For normal operation keep this pin logic 0.
Circuit Diagram:
0.1μF power supply decoupling capacitors placed near the supply pins. Use a 3.3nF capacitor
on the outputs of the accelerometer to minimize clock noise (from the switched capacitor
filter circuit). A/D sampling rate and any external power supply switching frequency should
be selected such that they do not interfere with the internal accelerometer sampling frequency
(11 kHz for the sampling frequency). This will prevent aliasing errors.
The compact board with few mounted components gives you the analog output voltage on the
connector pins.
