LG C1100 Service Manual page 30

AD6537B
Thermal
Shutdown
CHGDET
VBAT
KEYON
VRTC
DBBON
VEXT
VCXDEN
Figure 3-17. AD6537B POWER MODE LOGIC
2. LDO Block
1. There are 8LDOs in the AD6537B.
- VCORE : supplies Digital Baseband Processor core and AD6537 digital core
(1.8V, 80mA)
- VMEM : supplies external memory and the interface to the external memory on
the digital baseband processor (1.8V or 2.8V, 150mA)
- VEXT : supplies Radio digital interface and high voltage interface (2.8V,
170mA)
- VSIM : supplies the SIM interface circuitry on the digital processor and SIM
card (1.8V or 2.85V, 20mA)
- VRTC : supplies the Real-Time Clock module (1.8 V, 200 µA)
- VABB : supplies the analog portions of the AD6537
- VMIC : supplies the microphone interface circuitry (2.5 V, 1 mA)
- VVCXO : supplies the voltage controlled crystal oscillator ( 2.75 V, 10 mA)
THERM
DDLO
UVLO
VSMEn
Control Bit
POWERMODE
low: VCORE < 1.5V
high: VCORE > 1.5V
low: VMEM < 2.5V or 1.5V
high: VMEM > 2.5V or 1.5V
high: VEXT > 2.5V
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3. TECHNICAL BRIEF
Enable
Digital core
LDO Regulator
Mode
Enable
Memory Interface
LDO Regulator
Mode
Enable
External Interface
LDO Regulator
Mode
Enable
SIM Interface
LDO Regulator
Mode
Enable
VCXO
LDO Regulator
VCORE Comparator
VCORECP VCORE
VMEM Comparator
VMEMCP VMEM
VEXT Comparator
VEXTCP
VEXT
low: VEXT < 2.5V
VCORE
VMEM
VEXT
VSM
VVCXO