xE922-3GR Hardware User Guide
1VV0301272
Rev.0.8 2017-01-05
Reproduction forbidden without written authorization from Telit Communications S.p.A. - All Rights
Reserved.
Page 6 of 112
4.2.
Recommended operating conditions
.................................. 39
4.3.
Logic Level Specifications
........................................ 39
5.
Power supply
.................................................... 41
5.1.
Input supply
.................................................. 41
5.2.
Output supply
................................................. 42
5.2.1.
Linear voltage regulators .................................. 42
5.2.1.1.
VAUX_1P8V ............................................... 42
5.2.1.2.
VAUX_2P85V .............................................. 43
5.2.1.3.
VAUX_3P0V ............................................... 43
5.2.1.4.
VSIM1/2 ................................................. 44
5.2.2.
DC/DC stepdown
................................................. 44
5.2.2.1.
1V8_OUT
................................................. 44
5.3.
Typical system power consumption
................................... 45
5.4.
RTC backup
.................................................. 47
6.
Power ON/OFF and reset control
...................................... 49
6.1.
Power On
.................................................... 49
6.1.1.
ON_OFF key action
............................................... 49
6.1.2.
Switching ON due to charging
........................................ 50
6.1.3.
Switching on due to RTC alarm
....................................... 50
6.2.
Power off
.................................................... 50
6.2.1.
Soft power off
................................................... 50
6.2.2.
Emergency power off
.............................................. 50
6.3.
Reset
....................................................... 50
7.
Battery management
.............................................. 51
7.1.
Coulomb counter
............................................... 51
7.2.
Battery charging
............................................... 52
7.2.1.
Block diagram
................................................... 52
7.2.2.
Battery/charger-less operation
........................................ 54
8.
USIM interface
.................................................. 55
9.
USB port
....................................................... 57
10.
Display interface
................................................ 60
10.1.
MIPI-DSI
.................................................. 60