Autonomous 8-Angle Tip-Over Sensor with High Vibration Immunity MXD6240/6241AU FEATURES VDD P1 P0 P2 8 Pin-programmable angle thresholds Single-wire digital output Fully autonomous- no uC required 2-Axis Signal DSP & 3-state Built-in self-test functionality Sensor Condg Hyst. Output OUT &A/D Delay Driver Small, 6-pin 3 x 3mm LCC package Operates from 2.7V to 5.5V Supply No sensor resonance Trim & Ref & Clock & Vibration filter: tolerates 20 g p-p 50Hz Cal Bias Timing vibration with < 1 incremental angle error Circuits Gen Gen High reliability automotive process RoHS compliant GND Operates from -40 C to +125 C APPLICATIONS : Figure 1. FUNCTIONAL BLOCK DIAGRAM Motorcycle Fall-Down Detection Off-Road Vehicles Jetski, watercraft Other Tip-Over Detection (Space heaters, Irons, etc) The MXD6240/6241AU uses MEMSICs proprietary DESCRIPTION: thermal accelerometer technology. Because the The MXD6240/6241AU is an inclination sensor with 8 sensing element uses heated gas molecules instead built-in, pin-programmable angle thresholds. If the of a mechanical beam structure, the device is device orientation with respect to vertical exceeds the extremely robust and reliable, with 50,000g shock programmed threshold angle, the digital output tolerance, no possibility of stiction, virtually no changes state to alert the system to a tip-over or fall- mechanical resonance, and extremely high accuracy down event. An internal anti-vibration filter over temperature. This makes the device extremely provides >45dB attenuation above 25Hz, and >60dB well suited to harsh or high vibration environments, attenuation above 50Hz. where other sensors can exhibit false readings due to The MXD6240/6241AU is designed to run resonance or other errors. autonomously, making it ideal for systems where there The MXD6240AU output is a logic low under normal is no uC available. One of eight threshold angles (40, operation, and logic high during tip-over the 42.5, 45, 50, 55, 60, 65, and 70 degrees) is selected MXD6241AU uses the opposite output polarity by connecting each of three programming pins to Vdd (normally high, low during tip-over). A high-Z output or Gnd. The threshold accuracy is guaranteed to meet state signifies an internal self-test failure. +/-5 degrees (max) over a temperature range of -20C Both devices operate from a single 2.7V to 5.5V to +80C (Operation is guaranteed over -40C to supply, and are packaged in a small 6-pin, 3x3x1 mm +125C). LCC package. A built-in self-test function can detect a fault in the internal sensor, and if triggered will cause the output to go to a high impedance state. Information furnished by MEMSIC is believed to be accurate and reliable. MEMSIC, Inc. However, no responsibility is assumed by MEMSIC for its use, or for any One Technology Drive, Suite 325, Andover, MA 01810, USA infringements of patents or other rights of third parties which may result from Tel: +1 978 738 0900 Fax: +1 978 738 0196 its use. No license is granted by implication or otherwise under any patent or www.memsic.com patent rights of MEMSIC. MEMSIC MXC6240/41AU Rev.A (6/27/2016) Page 1 of 6 Formal release date: 8/18/2016 SENSOR CHARACTERISTICS: (TA=25C, V = 5V, unless otherwise specified. Typical values are specified at 25C) DD Parameter Conditions Min Typ Max Units 40, 42.5, 45, 50, Threshold Angles Pin-Programmable via P2, P1, P0 Deg 55, 60, 65, 70 Threshold Accuracy (Note 1) TA = -20C to +80C 2 5 Deg 20g p-p f 25Hz 3 Threshold Error due to Vibration Deg (Note 2) 20g p-p f 50Hz 0.5 Sensor Bandwidth (Note 3) 11 Hz Resonance (Note 4) Undetectable Hz Shock Tolerance 50,000 g Off-Axis Tilt Range (For rated accuracy) 15 Deg LOW-G Lockout Threshold (Note 5) 0.375 g Note 1: Guaranteed by design and characterization, using 4 limits. Note 2: This is the incremental threshold error due to the vibration signal, applied parallel to the y axis Note 3: The sensor has an inherent low pass filter characteristic, which is very effective in attenuating out of band vibration. Note 4: The thermal accelerometer sensors use heated gas molecules, and have no measurable resonance Note 5: The LOW-G Lockout feature disables tip-over detection if the magnitude of both X and Y acceleration vectors fall below 0.375g (as in the case of a free-fall or large off-axis tilt condition). See also Fault Detection. ELECTRICAL SPECIFICATIONS: (TA=25C, V = 5V, unless otherwise specified. Typical values are specified at 25C) DD Parameter Conditions Min Typ Max Units Supply Voltage 2.7 5.5 V Supply Current 0.8 3 mA Operating Temperature -40 125 C Output Update Rate (ODR) (Note 6) 2.7 3 3.3 Hz Power On Time VDD rising edge to angle detection active 300 500 ms Power On Reset Threshold 0.8 1.2 1.6 V VDD Rise Time (Note 7) 8 ms Note 6: This is the rate at which the logic state of the OUTPUT pin is updated. The output will typically change state within 1 2 ODR cycles of a change in tip-over orientation. The above applies for Vdd = 5V. At Vdd = 2.7V, the ODR slows by ~15%. Note 7: Maximum allowable power supply rise time from 0.25V to 2.7V (minimum). Slower VDD rise time may cause erroneous data retrieval from OTP memory at power-up. DIGITAL PARAMETERS (TA=25C, V = 5V, unless otherwise specified. Typical values are specified at 25C) DD Parameter Conditions Min Typ Max Units Logic Input Low P2, P1, P0 Inputs 0 0.3*Vdd V Logic Input High P2, P1, P0 Inputs 0.7*Vdd Vdd V Logic Output Low Sinking 0.5mA (Note 8) 0.1*Vdd V Logic Output High Sourcing 0.5mA (Note 8) 0.9*Vdd Logic Output High-Z After sensor fault is detected 1 Mohm Note 8: The output driver is capable of sourcing and sinking much higher currents, but it is recommended to keep the load current below 0.5mA to avoid thermal gradients which may affect the angle threshold accuracy. MEMSIC MXC6240/41AU Rev.A (6/27/2016) Page 2 of 6 Formal release date: 8/18/2016