MMA8451QT Freescale Semiconductor, MMA8451QT Datasheet - Page 38

• Manufacturer Part Number: MMA8451QT
• Description: Board Mount Accelerometers LOW G 3-AXIS 14BT EX VLT
• Manufacturer: Freescale Semiconductor

Specifications of MMA8451QT

• Sensing Axis: X, Y, Z
• Acceleration: 2 g, 4 g, 6 g
• Digital Output - Number Of Bits: 8 bit, 14 bit
• Supply Voltage (max): 3.6 V
• Supply Voltage (min): 1.95 V
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Digital Output - Bus Interface: I2C
• Shutdown: Yes
• Sensitivity: 1024 count/g, 2048 count/g, 4096 count/g
• Package / Case: QFN-16
• Output Type: Digital
• Acceleration Range: ± 2g, ± 4g, ± 8g
• No. Of Axes: 3
• Ic Interface Type: I2C, Serial
• Sensor Case Style: QFN
• No. Of Pins: 16
• Supply Voltage Range: 1.95V To 3.6V
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

0x27: PULSE_LTCY Pulse Latency Timer Register
pulses are ignored. Note: This timer must be set for single pulse and for double pulse.
and Oversampling mode multiplied by 255. The timing also changes when the Pulse LPF is enabled or disabled.
Table 44. PULSE_LTCY Description
38
MMA8452Q
0x27 PULSE_LTCY Register (Read/Write)
The bits LTCY7 through LTCY0 define the time interval that starts after the first pulse detection. During this time interval, all
The minimum time step for the pulse latency is defined in
LTCY7
Bit 7
LTCY[7:0]
Table 43. Time Step for PULSE Time Limit (Reg 0x0F) Pulse_LPF_EN = 0
Table 45. Time Step for PULSE Latency @ ODR and Power Mode (Reg 0x0F) Pulse_LPF_EN = 1
Table 46. Time Step for PULSE Latency @ ODR and Power Mode (Reg 0x0F) Pulse_LPF_EN = 0
ODR (Hz)
ODR (Hz)
ODR (Hz)
12.5
6.25
1.56
12.5
6.25
1.56
12.5
6.25
1.56
800
400
200
100
800
400
200
100
800
400
200
100
50
50
50
LTCY6
Bit 6
Normal
Normal
Normal
Latency Time Limit. Default value: 0000_0000
0.159
0.159
0.319
0.638
0.638
1.276
0.318
0.318
0.638
1.276
1.28
1.28
1.28
1.28
2.56
10.2
10.2
10.2
10.2
2.56
2.56
2.56
2.56
5.1
Max Time Range (s)
Max Time Range (s)
Max Time Range (s)
LPLN
LTCY5
LPLN
LPLN
0.159
0.159
0.319
0.638
0.638
1.276
0.318
0.318
0.638
1.276
1.28
2.56
10.2
40.8
40.8
40.8
2.56
10.2
10.2
10.2
Bit 5
5.1
5.1
5.1
5.1
HighRes
HighRes
HighRes
0.159
0.159
0.159
0.159
0.159
0.159
0.159
0.159
0.638
1.276
1.276
1.276
1.276
1.276
1.276
1.276
0.318
0.318
0.318
0.318
0.318
0.318
0.318
0.318
LTCY4
Bit 4
Table 45
0.159
0.319
0.638
0.638
1.276
0.318
0.638
1.276
1.28
2.55
10.2
10.2
10.2
2.56
10.2
40.8
81.6
81.6
2.56
20.4
20.4
20.4
5.1
5.1
LP
LP
LP
and
LTCY3
Bit 3
Table
Normal
Normal
Normal
0.625
0.625
1.25
1.25
1.25
2.5
2.5
2.5
10
20
40
40
40
40
10
10
10
10
5
5
5
5
5
5
46. The maximum time is the time step at the ODR
LTCY2
Bit 2
LPLN
LPLN
LPLN
0.625
0.625
1.25
1.25
1.25
160
160
160
2.5
2.5
2.5
Time Step (ms)
Time Step (ms)
Time Step (ms)
20
20
20
10
20
40
10
40
40
40
5
5
5
HighRes
HighRes
HighRes
0.625
0.625
0.625
0.625
0.625
0.625
0.625
0.625
1.25
1.25
1.25
1.25
1.25
1.25
1.25
1.25
2.5
5
5
5
5
5
5
5
LTCY1
Bit 1
Freescale Semiconductor
0.625
1.25
1.25
160
320
320
2.5
2.5
2.5
LP
LP
LP
10
40
40
40
10
20
40
10
20
80
80
80
5
5
5
LTCY0
Bit 0
Sensors