Hello,
I am using a TESEO LIV3F which supply pins are connected as follow :
- Pin 8 (VCC) : 2.4v supplied by a SMPS that may be turned OFF
- Pin 7 (VCC IO) : 3.2v supplied by a LDO that may be turned OFF
- Pin 6 (Vbatt) : Permanent 3.2v provided by batteries
By reading the docs I understood that the module, once powered ON for the first time, needs 12.5 min to acquire the almanac followed by the euphemeris, then they are both stored in the backup RAM that belongs to the RTC domain supplied by Vbatt (permanent supply in this case).
After the FIX have been obtained for this session, the module is no longer needed and the CPU sends a PSTMFORCESTANDBY for 99999 seconds (is it mandatory ?), after receiving a PSTMFORCESTANDBYOK, the module enters standby mode and the CPU shuts down the supplies from VCC and VCC IO, leaving only Vbatt with 3.2v supply.
The LIV3F's RTC clock keeps track of the time and stores the almanac and euphemeris data, after approx 24 hours the module is powered on again (VCC and VCC IO pins), the CPU sends a PSTMWARM (is it mandatory ?) to force the module to use the almanac data previously stored and the RTC timestamp, which allows to make a FIX as soon as possible.
I will be using Adaptive and Cyclic low power modes with a 3s fix period in order to lower the consumption while the module is active.
Can you please confirm that this sequence is followed by the module ? Also, is there a way to have even less Time To First Fix ? I am thinking of enabling the ST-AGNSS (since i have no network connexion) in order to predict the ephemerides at each startup to get a faster Time To First Fix.
Thanks,
