Power Management - LG B2050 Service Manual

3.6.5 Power Management

CSFS
CSDI
CSDO
1.8V, 80mA
VCORE
1.8 or 2.8V, 150mA
VMEM
VEXT
2.8V, 170mA
VSIM
1.8 or 2.85V, 20mA
VRTC
1.8V, 20 A
VCXOEN
DBBON
RESET
Figure 3-16 AD6537B POWER MANAGEMENT SECTION
1. Power up sequence logic
1. The AD6537B controls power on sequence
2. Power on sequence
-If a battery is inserted, the battery powers the 8 LDOs.
-Then if PWRONKEY is detected, the LDOsoutput turn on.
-REFOUT is also enabled
-Reset is generated and send to the AD6527
AD6537B
Control
Serial
Port
Didital Core
LDO Regulator
Memory Interface
LDO Regulator
External Interface
LDO Regulator
SIM Interface
LDO Regulator
RTC
LDO Regulator
Regulator
Control
- 33 -
Baseband Analog
LDO Regulator
Microphone
LDO Regulator
VCXO VVCXO
LDO Regulator
Battery
Charer GATEDRIVE
BATTYPE
ISENSE
KEYON
KEYOUT
Power-on
Reset Generator
3. TECHNICAL BRIEF
VABB
VMIC
2.5V, 1mA
2.75V, 10mA
VCHG