3. TECHNICAL BRIEF
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LGE Internal Use Only
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Only for training and service purposes
The ADC and the oscillator for the ADC needs the VDD_ADC supply voltage from the LADC LDO. LADC uses
either the charger voltage VDD_CHARGE or VDDRTC as input voltage. The input voltage is selected
3. TECHNICAL BRIEF
automatically by a bulk switch circuit. LADC, the ADC and the oscillator are enabled on request for every battery
measurement if the charger unit is not running. This is handled by an ADC control block in one of the state-
machines. If the charger unit is running the ADC is controlled by the charger state-machine
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Figure.3.2.1 First Part of the State Machine, Running in Different Power Domains than the Second Part
The ADC and the oscillator for the ADC needs the VDD_ADC supply voltage from the LADC LDO. LADC uses
either the charger voltage VDD_CHARGE or VDDRTC as input voltage. The input voltage is selected
automatically by a bulk switch circuit. LADC, the ADC and the oscillator are enabled on request for every battery
measurement if the charger unit is not running. This is handled by an ADC control block in one of the state-
machines. If the charger unit is running the ADC is controlled by the charger state-machine
Figure.3.3.2 First Part of the State Machine, Running in Different Power Domains than the Second Part
BAT low
all LDO’s off
PMU lpmu_pd=0
LPBG on
BAT OK
LRTC on
oscillator on
LPMU-ULPM path on
50kHz OSC setting
wait for oscillator o.k.
PMU SM1 ON
start PMU SM1
release reset of PMU SM1
PMU SM1 SYSOFF
VBAT < 2.5V-e
SYSTEM_OFF
small dig
ital sta
te machine in
ultr
a lo
w po
w
er LP
MU domain
analog cir
cuit implemen
ta
tion
VBAT < SYSOFF
VBAT > 2.5V
VBAT > 2.5V
VPMU o.k.
VBAT > 2.5V
LPMU o.k.
Oscillator o.k.
VBAT > 2.5V
LPMU o.k.
Oscillator o.k.
ON key event
RTC alarm
charger delect
first_connect
Figure.3.2.2 First Part of the State Machine, Running in Dierent Power Domains than the Second Part