NXP Semiconductors
FXPS7115D4
Digital absolute pressure sensor, 40 kPa to 115 kPa
The pressure threshold registers hold independent unsigned 16-bit values for a high and
a low threshold. The window comparator threshold alignment is shown in Section 7.3.4.4
"Absolute pressure output data scaling equation".
If either the high or low threshold is programmed to 0000h, comparisons are disabled for
that threshold only. The interrupt comparison still functions for the opposite threshold.
If both the high and low thresholds are programmed to 0000h, the interrupt output is
disabled.
7.7.15 P_CAL_ZERO - pressure calibration registers (address 4Ch, 4Dh)
The pressure calibration registers contain user programmable values to adjust the offset
of the absolute pressure.
These registers can be written during initialization but are locked once the ENDINIT bit
is set (see Section 7.7.4 "DEVLOCK_WR - lock register writes register (address 10h)").
These registers are included in the read/write array error detection. Changes to these
registers reset the DSP data path. The contents of the SNSDATA_x registers are not
guaranteed until the DSP has completed initialization, as specified in Table 102. Reads
of the SNSDATA_x registers and sensor data requests should be prevented during this
time.
Table 73.ꢀP_CAL_ZERO - pressure calibration registers (address 4Ch, 4Dh) bit allocation
Location
Address
4Ch
Bit
Register
7
6
5
4
3
2
1
0
P_CAL_ZERO_L
P_CAL_ZERO_H
P_CAL_ZERO[7:0]
P_CAL_ZERO[15:8]
4Dh
Reset
0
0
0
0
0
0
0
0
Access
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
The P_CAL_ZERO register value is a signed 16-bit value that is directly added to the
internally calibrated pressure signal value as shown in Equation 6. The equation applies
to the values in the 16-bit SNSDATA registers.
(6)
Where:
PABSkPa = The absolute pressure output in kPa
PABSLSB = The internal trimmed absolute pressure output in LSB
PABSOFFLSB = The internal trimmed absolute pressure output value at 0 kPa in LSB
PABSSENSE = The trimmed absolute pressure sensitivity in LSB/kPa
UserOffset = The 16-bit signed value programmed into the P_CAL_ZERO register
Note: The pressure calibration registers enable range and resolution options beyond the
specified values of the device. The user must take care to ensure that the value stored in
this register does not result in a compressed output range or a railed output.
FXPS7115D4
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© NXP B.V. 2019. All rights reserved.
Product data sheet
Rev. 3 — 5 December 2019
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