ST LPS22HB - 5 Use Case and Configuration Example for the LPS25 HB; Main Device Settings; Table 3: ODR Configuration

Use case and configuration example for the
LPS25HB
AN4672
20/24
DocID027655 Rev 3
5 Use case and configuration example for the
LPS25HB
The LPS25HB provides great flexibility to the designer and can be configured depending
on the specific application requirements. Requisites such as resolution, power
consumption, acquisition and measurement times can be set accordingly to the application
context.
The LPS25HB can operate in two different modalities:
 Power Down modality
 Continuous modality
In Power Down modality, no measurements are taken; this is the default sensor
configuration PD [7] bit of CTRL_REG1 (0x20) set to “0”.
In Continuous mode, the device can detect pressure and temperature data, depending on
the defined data output frequency.
In particular, two operation modes are available as continuous modality:
 One-shot mode
 Active mode
In continuous modality, measurements data output are available on the output register with
a refresh frequency defined by the selected output data rate (ODR [2, 0] bits of
CTRL_REG1 (0x20)) as described in table
Table 3: ODR configuration
ODR2
ODR1
ODR0
Pressure (Hz)
Temperature (Hz)
0
0
0
One shot
0
0
1
1 Hz
1 Hz
0
1
0
7 Hz
7 Hz
0
1
1
12.5 Hz
12.5 Hz
1
0
0
25 Hz
25 Hz
At device boot, the ODR[2,0] bits default configuration loaded is ‘000’ and the device goes
in one-shot mode, that allows to get a single measurement of pressure and temperature, by
toggling the ONE_SHOT bit in CTRL_REG2 (0x21). Once the measurement is acquired,
the ONE_SHOT bit is self-cleared to the default value “0” (Idle), the new data are available
in the output registers, the STATUS_REG(0x27) bits are updated and the device goes back
in power-down mode.
In active mode, power-down bit set to “1”, according to the ODR configuration selected,
different pressure and temperature resolution profiles are available as described in the next
section.
5.1 Main device settings
In Active and One shot mode, depending on the specific application, a set of configuration
settings is available, ranging from low power to ultra-high resolution profiles. The right
trade-off among, resolution, output data rate and power consumption has to be identified,
to make the sensor suitable for the specific design requirements.