LG GB108 Service Manual page 38

The integrated power management also provides the control state machine for system start up,
including start up with discharged batteries, pre-charging and system reset control.
After system start up several methods are implemented for active and idle power saving.
LDO output voltage selection
• LD1, LIO, LSIM, LBUF output voltage programmable by software.
• LMEM output voltage is selectable by pin configuration upon startup.
Active and idle power saving options:
• The flexible clock switching options allow minimizing the power consumption during the
operation phases of the E-GOLDvoice.
• Current consumption during the standby mode is minimized by reducing the clock to 32 kHz and
switching it off for most of the device. In addition, the power supply for the TEAKLite ROM is
switched off and the controller RAM is switched to a power saving mode.
Start-up and Reset Control State Machine Features
• Power up upon battery insertion, push button, alarm, charger connection.
• Detection of battery exchange or re-insertion.
• Complete start-up sequence management.
• System turn-on, system turn-off operation management including emergency (under-voltage)
and programmed shutdown functions.
• Internal reset of the baseband.
• Tristate function of the baseband module.
• Standby mode controlled by VCXO_EN provided by SCCU module.
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