Freescale Semiconductor Energy Efficient Solutions Xtrinsic MMA8452Q, Технические данные: Техническая информация

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MMA8452Q
Sensors
Freescale Semiconductor, Inc.
9
2.4 Absolute Maximum Ratings
Stresses above those listed as “absolute maximum ratings” may cause permanent damage to the device. Exposure to
maximum rating conditions for extended periods may affect device reliability.
3 Terminology
3.1 Sensitivity
The sensitivity is represented in counts/g. In 2g mode the sensitivity is 1024 counts/g. In 4g mode the sensitivity is
512 counts/g and in 8g mode the sensitivity is 256 counts/g.
3.2 Zero-g Offset
Zero-g Offset (TyOff) describes the deviation of an actual output signal from the ideal output signal if the sensor is stationary. A
sensor stationary on a horizontal surface will measure 0g in X-axis and 0g in Y-axis whereas the Z-axis will measure 1g. The output
is ideally in the middle of the dynamic range of the sensor (content of OUT Registers 0x00, data expressed as 2's complement
number). A deviation from ideal value in this case is called Zero-g offset. Offset is to some extent a result of stress on the MEMS
sensor and therefore the offset can slightly change after mounting the sensor onto a printed circuit board or exposing it to
extensive mechanical stress.
3.3 Self-Test
Self-Test checks the transducer functionality without external mechanical stimulus. When Self-Test is activated, an electrostatic
actuation force is applied to the sensor, simulating a small acceleration. In this case, the sensor outputs will exhibit a change in
their DC levels which are related to the selected full scale through the device sensitivity. When Self-Test 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.
Table 5. Maximum Ratings
Rating Symbol Value Unit
Maximum Acceleration (all axes, 100
μ
s) g
max
5,000 g
Supply Voltage VDD -0.3 to + 3.6 V
Input voltage on any control pin (SA0, SCL, SDA) Vin -0.3 to VDDIO + 0.3 V
Drop Test D
drop
1.8 m
Operating Temperature Range T
OP
-40 to +85 °C
Storage Temperature Range T
STG
-40 to +125 °C
Table 6. ESD and Latchup Protection Characteristics
Rating Symbol Value Unit
Human Body Model HBM ±2000 V
Machine Model MM ±200 V
Charge Device Model CDM ±500 V
Latchup Current at T = 85°C — ±100 mA
This device is sensitive to mechanical shock. Improper handling can cause permanent damage of the part or
cause the part to otherwise fail.
This device is sensitive to ESD, improper handling can cause permanent damage to the part.