3. TECHNICAL BRIEF
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Copyright © 2013 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
Copyright © 2007 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
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3. TECHNICAL BRIEF
Single-Step RTC LDO (VRTC)
The single-step RTC LDO is a linear regulator that can charge up a capacitor-type backup coin cell to 2.8
V, which also supplies the RTC module even at the absence of the main battery. The single-step LDO
features the reverse current protection and is optimized for ultra low quiescent current while sustaining
the RTC function as long as possible.
SIM LDO (VSIM)
The SIM LDO is a linear regulator that could source 60mA (max) with 1.8V or 3.0V output voltage
selection based on the supply specs of subscriber identity modules (SIM) card. It supplies the SIM card
and SIM level shifter circuitry in the handset. The Vsim LDO is controlled independently by the register
named VSIM_EN.
SIM2 LDO (VSIM2)
The SIM2 LDO is a linear regulator that could source 60mA (max) with 1.3V, 1.5V, 1.8V, 2.5V, 2.8V, 3.0V or
3.3V output voltage selection based on the supply specs of the 2nd subscriber identity modules (SIM)
card. It supplies the 2nd SIM card and SIM level shifter circuitry in the handset. The Vsim2 LDO is
controlled independently by the register named VSIM2_EN.
USB LDO (VUSB)
The USB LDO is a linear regulator that could source 60mA (max) with 3.3V output dedicated for USB
circuitry. It is controlled independently by the register named RG_VUSB_EN.
Bluetooth LDO (VBT)
The VBT LDO is a linear regulator that could source 100mA (max) with 1.3V, 1.5V, 1.8V, 2.5V, 2.8V, 3.0V,
3.1V or 3.3V output for Bluetooth module. It is controlled independently by the register named
RG_VBT_EN
.
Camera Analog LDO (VCAMA)
The Vcama LDO is a linear regulator that could source 250mA (max) with 1.5V, 1.8V, 2.5V or 2.8V output
which is selected by the register named VCAMA_SEL[1:0]. It supplies the analog power of the camera
module. Vcama
is controlled independently by the register named RG_VCAMA_EN.
Camera Digital LDO (VCAMD)
The Vcamd LDO is a linear regulator that could source 100mA (max) with 1.3V, 1.5V, 1.8V, 2.5V, 2.8V,
3.0V or 3.3V output which is selected by the register named VCAMD_SEL[2:0]. It supplies the digital
power of the camera module. Vcamd is controlled independently by the register named
RG_VCAMD_EN.
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