Specifications

LEON-G100/G200 - System Integration Manual
GSM.G1-HW-09002-C Preliminary System description
Page 27 of 75
on the application board, in range from 1.8 V to 3.3 V. It should also be available when the module is in power-
off mode. Other possibility is to use a push-pull output of the external device, but take care to fix the proper
level in all the possible scenarios to avoid an inappropriate switch-on of the module.
Figure 13: Power on (PWR_ON) application circuits using a push button or using an application processor
1.6.1.3 RTC alarm
The module can be switched-on by the RTC alarm if a valid voltage is applied to the VCC pin, when Real Time
Clock system reaches a pre-defined scheduled time. The RTC system will then initiate the boot sequence by
indicating to the power management unit to turn on power. Also included in this setup is an interrupt signal
from the RTC block to indicate to the baseband processor, that a RTC event has occurred.
1.6.1.4 Rising edge on V_CHARGE and CHARGE_SENSE (LEON-G200 only)
The module can be switched-on by a charger: if the power management unit detects that a charger is connected
to the module through the V_CHARGE and CHARGE_SENSE pins, it turns on power and the module is
switched on in charge mode.
1.6.1.5 Additional considerations
If a valid battery voltage is connected to VCC before the detection of a start-up event, most input-output pads of
the baseband chipset are locked in tri-state. The power down tri-state function isolates the outputs of the
module from its environment, when no proper operation of the outputs can be guaranteed. To avoid an increase
of the module current consumption in power down mode, any external signal of the digital interfaces connected
to the module must be set low or tri-stated when the module is in not-powered mode or in the power-off mode.
After the detection of a start-up event, during the power-on sequence, the baseband core is held in reset state
before enabling the input-output pads. Any signal of the module digital interfaces is held to the reset state until
the application starts. See Figure 14. The reset state of all the module input-output pins is reported in the pin
description table of the LEON-G100/G200 Data Sheet [1].
2
19
V_BCKP
PWR_ON
LEON-G100/G200
Power-on
push button
10 k
Application Processor
19
PWR_ON
LEON-G100/G200
10k
2
19
V_BCKP
PWR_ON
LEON-G100/G200
Power-on
push button
10 k
Application Processor
19
PWR_ON
LEON-G100/G200
10k