Datasheet

Sensors
6 NXP Semiconductors
MMA8452Q
2 Mechanical and Electrical Specifications
2.1 Mechanical characteristics
Table 2. Mechanical characteristics @ VDD = 2.5 V, VDDIO = 1.8 V, T = 25 °C unless otherwise noted.
Parameter Test conditions Symbol Min Typ Max Unit
Measurement range
(1)
1. Dynamic range is limited to 4 g when the low-noise bit in register 0x2A, bit 2 is set.
FS[1:0] set to 00
2 g mode
FS
—±2—
g
FS[1:0] set to 01
4 g mode
—±4—
FS[1:0] set to 10
8 g mode
—±8—
Sensitivity
FS[1:0] set to 00
2 g mode
So
— 1024 —
counts/g
FS[1:0] set to 01
4 g mode
— 512 —
FS[1:0] set to 10
8 g mode
— 256 —
Sensitivity accuracy
(2)
2. Sensitivity remains in spec as stated, but changing oversampling mode to low power causes 3% sensitivity shift. This behavior is also seen
when changing from 800 Hz to any other data rate in the normal, low noise + low power or high resolution mode.
— Soa — ±2.64 — %
Sensitivity change vs. temperature
FS[1:0] set to 00
2 g mode
TCSo
—
±0.008
—
%/°C
FS[1:0] set to 01
4 g mode
——
FS[1:0] set to 10
8 g mode
——
Zero-g level offset accuracy
(3)
3. Before board mount.
FS[1:0] 2 g, 4 g, 8 g TyOff — ±17 — mg
Zero-g level offset accuracy post-board mount
(4)
4. Post-board mount offset specifications are based on an 8-layer PCB, relative to 25°C.
FS[1:0] 2 g, 4 g, 8 g TyOffPBM — ±20 — mg
Zero-g level change vs. temperature –40 °C to 85 °C TCOff — ±0.15 — mg/°C
Self-test output change
(5)
X
Y
Z
5. Self-test is one direction only.
FS[1:0] set to 0
4 g mode
Vst
—
—
—
+44
+61
+392
—
—
—
LSB
ODR accuracy
2-MHz clock — — — ±2 —
%
Output data bandwidth — BW ODR/3 — ODR/2 Hz
Output noise Normal mode ODR = 400 Hz Noise — 126 — µg/√Hz
Output noise low-noise mode
(1)
Normal mode ODR = 400 Hz Noise — 99 — µg/√Hz
Operating temperature range — Top –40 — +85 °C