PMMA7450LR2 Freescale Semiconductor, Inc, PMMA7450LR2 Datasheet - Page 7

• Manufacturer Part Number: PMMA7450LR2
• Description: ?2g/?4g/?8g Three Axis Low-g Digital Output Accelerometer
• Manufacturer: Freescale Semiconductor, Inc

Pulse Detection Mode
The level detection is also enabled in this mode. The pulse detected by the acceleration signal is enabled with single pulse and
double pulse detection allowing the choice of either positive, negative or absolute value pulse detection.
Setting for Motion Detection
value of one of the enabled axes exceeds the threshold limit value, logic high level is output to INT1 or INT2 pin and indicates
the event was detected.
Setting for Free Fall Detection
Timer Value Register, logic high level is output to INT1 or INT2 pin indicating freefall was detected.
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In pulse detection mode, both 2g/4g and 8g range are available. Measurements for x, y and z in 2g/4g or 8g mode are enabled.
For the PDPOL bit in Control Register 2 (Address: $19) the register should be set to “0” for motion detection. When the output
To configure the MMA7450L for freefall detection, set the PDPOL bit in Control Register 2 (Address: $19) to 1.
Next, set the register for Time Window for 2nd pulse value (Address $1E) to 0.
When the output values of all enabled axes are below the threshold limit continuously during the period specified in Latency
– If PDPOL = 0 and all three axes are enabled for detection
– When the condition below was detected, logic high level outputs to INT1 or INT2
– “XOUT ≥Threshold” or “YOUT ≥Threshold” or
“ZOUT ≥Threshold”
PULSE DETECTION MODE
MMA7450L
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