Datasheet
Sensors
24 NXP Semiconductors
MMA8452Q
0x0F: HP_FILTER_CUTOFF high-pass filter register
This register sets the high-pass filter cutoff frequency for removal of the offset and slower changing acceleration data. The output
of this filter is indicated by the data registers (0x01-0x06) when bit 4 (HPF_OUT) of register 0x0E is set. The filter cutoff options
change based on the data rate selected as shown in Table 18. For details of implementation on the high-pass filter, refer to NXP
application note AN4071.
0x0F: HP_FILTER_CUTOFF: high-pass filter register (read/write)
Bit
7
Bit
6
Bit
5
Bit
4
Bit
3
Bit
2
Bit
1
Bit
0
0 0 Pulse_HPF_BYP Pulse_LPF_EN 0 0 SEL1 SEL0
Table 17. High-pass filter cutoff register descriptions
Field Description
Pulse_HPF_BYP
Bypass high-pass filter for pulse processing function.
0: HPF enabled for pulse processing, 1: HPF bypassed for pulse processing
Default value: 0.
Pulse_LPF_EN
Enable low-pass filter for pulse processing function.
0: LPF disabled for pulse processing, 1: LPF enabled for pulse processing
Default value: 0.
SEL[1:0]
HPF cutoff frequency selection.
Default value: 00 (see
Table 18).
Table 18. High-pass filter cutoff options
SEL1 SEL0 800 Hz 400 Hz 200 Hz 100 Hz 50 Hz 12.5 Hz 6.25 Hz 1.56 Hz
Oversampling mode = normal
0 0 16 Hz 16 Hz 8 Hz 4 Hz 2 Hz 2 Hz 2 Hz 2 Hz
0 1 8 Hz 8 Hz 4 Hz 2 Hz 1 Hz 1 Hz 1 Hz 1 Hz
1 0 4 Hz 4 Hz 2 Hz 1 Hz 0.5 Hz 0.5 Hz 0.5 Hz 0.5 Hz
1 1 2 Hz 2 Hz 1 Hz 0.5 Hz 0.25 Hz 0.25 Hz 0.25 Hz 0.25 Hz
Oversampling mode = low noise low power
0 0 16 Hz 16 Hz 8 Hz 4 Hz 2 Hz 0.5 Hz 0.5 Hz 0.5 Hz
0 1 8 Hz 8 Hz 4 Hz 2 Hz 1 Hz 0.25 Hz 0.25 Hz 0.25 Hz
1 0 4 Hz 4 Hz 2 Hz 1 Hz 0.5 Hz 0.125 Hz 0.125 Hz 0.125 Hz
1 1 2 Hz 2 Hz 1 Hz 0.5 Hz 0.25 Hz 0.063 Hz 0.063 Hz 0.063 Hz
Oversampling mode = high resolution
0 0 16 Hz 16 Hz 16 Hz 16 Hz 16 Hz 16 Hz 16 Hz 16 Hz
0 1 8Hz 8Hz 8Hz 8Hz 8Hz 8Hz 8Hz 8Hz
1 0 4Hz 4Hz 4Hz 4Hz 4Hz 4Hz 4Hz 4Hz
1 1 2 Hz 2 Hz 2 Hz 2 Hz 2 Hz 2 Hz 2 Hz 2 Hz
Oversampling mode = low power
0 0 16 Hz 8 Hz 4 Hz 2 Hz 1 Hz 0.25 Hz 0.25 Hz 0.25 Hz
0 1 8 Hz 4 Hz 2 Hz 1 Hz 0.5 Hz 0.125 Hz 0.125 Hz 0.125 Hz
1 0 4 Hz 2 Hz 1 Hz 0.5 Hz 0.25 Hz 0.063 Hz 0.063 Hz 0.063 Hz
1 1 2 Hz 1 Hz 0.5 Hz 0.25 Hz 0.125 Hz 0.031 Hz 0.031 Hz 0.031 Hz