Telit Wireless Solutions SE868-A, Product User Manual

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SE868Kx-Ax Family Product User Guide
1VV0301201 Rev. 5
Page 24 of 83 2021-07-15
Not Subject to NDA
Power Management Modes
The receiver supports operating modes that reduce overall current consumption with
less frequent position fixes. Availability of GNSS signals in the operating environment will
be a factor in choosing power management modes. The designer can choose a mode that
provides the best trade-off of navigation performance versus power consumption.
The various power management modes can be enabled by sending the desired command.
Power Management - Command Summary
$PMTK Cmd Type State
Full Power To Exit (wake) from a commanded low-power state
225 0 Full
Perpetual Backup To wake:Force_ON Signal (MT3333 only)
225 4 Backup
Standby To wake:Character to Rx
161 0 Stop
161 1 Backup
Periodic (MT3333 only)
223 -
Specify Extended
Parameters
225 1 Backup
225 2 Standby
Always Locate (MT3333 and old MT3337 only, Not on new MT3337E)
223 -
Specify Extended
Parameters
225 8 Standby
225 9 Backup
GLP (MT3333 only)
262
0 Disable
262 3 Enable
Table 6: Power Management Command Summary
4.14.1. Full Power Continuous Mode
The receiver starts in full power continuous mode when powered up. This mode uses the
acquisition engine to search for all possible satellites at full performance, resulting in
the highest sensitivity and the shortest possible TTFF.
The receiver then switches to the tracking engine to lower the power consumption when:
•
A valid GPS/GNSS position is obtained
•
The ephemeris for each satellite in view is valid
To return to Full Power mode from a low power mode, send a $PMTK225,0*2B command
just after the module wakes up from its previous sleep cycle.