Datasheet

Bosch Sensortec | BME680 Datasheet
14 | 50
Modifications reserved |Data subject not change without notice | Printed in Germany
Document number: BST-BME680-DS001-00 Revision_1.0_072017
3. Sensor usage
3.1 Sensor modes
The sensor supports low-level power modes: sleep and forced mode. These modes can be selected using the mode<1:0>
control register (see Section 5.3.1.3). The key differences between the modes are summarized in Table 10.
After a power-up sequence, the sensor automatically starts in sleep mode. If the device is currently performing a
measurement, execution of mode switching commands is delayed until the end of the currently running measurement period.
It is important to note that, further mode change commands or other write commands to the control registers are ignored until
the mode change command has been executed. All control registers should be set to the desired values before writing to the
mode register.
Table 10: Low-level operation modes
Operation mode
mode<1:0>
Key features
Sleep
00
 No measurements are performed
 Minimal power consumption
Forced mode
01
 Single TPHG cycle is performed
 Sensor automatically returns to sleep mode afterwards
 Gas sensor heater only operates during gas measurement
In forced mode, temperature, pressure, humidity and gas conversion are performed sequentially. Such a measurement cycle
is abbreviated as TPHG (Temperature, Pressure, Humidity and Gas) in the following descriptions. Up to 10 temperature set-
points and heating durations for the gas sensor hot plate can be stored in the sensor registers. In the following, these set-
points and the corresponding measurements are identified as G0 – G9.Figure 1 illustrates the handling of these measurement
sequences and the gas sensor hot plate is heated for the forced mode.
Figure 1: Sequence of ADC and gas sensor heater operation