Power Management - LG -A290 Service Manual

3.2 Power Management

Power management unit, so called PMU, is integrated into analog part. To facilitate software control and interface design,
PMU control share the CCI interface along with other analog parts, such as BBTX, BBRX, VBI and ABI during FT.
3.2.1 Low Dropout Regulators(LDOs), Buck converterand Reference
The PMU Integrates 1 LDOs that are optimized for their given functions by balancing quiescent current, dropout
voltage, line/load regulation, and output noise.
 RF LDO (Vrf)
The RF LDO is a linear regulator that could source 180mA (max) with .8V output voltage. It supplies the RF circuitry of
the handset. The LDO is optimized for high performance and adequate quiescent current.
LGE Internal Use Only
MT6253 PMU System
Charger
System
KPLED
Driver
SIM IO 1
SIM IO 
Backlight
Power-on
Sequence /
Protection
Logic
Figure. 3.2.1 PMU system block diagram
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3. TECHNICAL BRIEF
LDOS
Buck
Boost
Vibrator
Driver
Driver
Speaker
Driver
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