LIS2L02AL_06 STMICROELECTRONICS [STMicroelectronics], LIS2L02AL_06 Datasheet - Page 8

• Manufacturer Part Number: LIS2L02AL_06
• Description: MEMS INERTIAL SENSOR:2-axis - +/-2g ultracompact linear accelerometer
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

Mechanical and electrical specifications
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Self Test allows to test the mechanical and electric part of the sensor, allowing the seismic
mass to be moved by means of an electrostatic test-force. The Self Test function is off when
the ST pin is connected to GND. When the ST pin is tied at Vdd an actuation force is applied
to the sensor, simulating a definite input acceleration. In this case the sensor outputs will
exhibit a voltage change in their DC levels which is related to the selected full scale and
depending on the Supply Voltage through the device sensitivity. When ST is activated, the
device output level is given by the algebraic sum of the signals produced by the acceleration
acting on the sensor and by the electrostatic test-force. If the output signals change within
the amplitude specified inside Table 2, than the sensor is working properly and the
parameters of the interface chip are within the defined specification.
Output impedance describes the resistor inside the output stage of each channel. This
resistor is part of a filter consisting of an external capacitor of at least 1nF and the internal
resistor. Due to the high resistor level only small, inexpensive external capacitors are
needed to generate low corner frequencies. When interfacing with an ADC it is important to
use high input impedance input circuitries to avoid measurement errors. Note that the
minimum load capacitance forms a corner frequency beyond the resonance frequency of
the sensor. For a flat frequency response a corner frequency well below the resonance
frequency is recommended. In general the smallest possible bandwidth for an particular
application should be chosen to get the best results.
LIS2L02AL