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LGE Internal Use Only
Copyright © 2010 LG Electronics. Inc. All right reserved.
Only for training and service purposes
3. TECHNICAL BRIEF
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ΟΝΪ͑ΗΠΣ͑ΥΣΒΚΟΚΟΘ͑ΒΟΕ͑ΤΖΣΧΚΔΖ͑ΡΦΣΡΠΤΖΤ
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3. TECHNICAL BRIEF
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Digital Core Buck Converter (Vcore)
The digital core regulator is a DC-DC step-down (Buck converter) that could source 200mA(max) with
1.2V to 0.9V programmable output voltage based on software register setting
.
It supplies the power for
baseband circuitry of the SoC. The buck converter is optimized for high efficiency and low quiescent
current.
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Digital IO LDO (Vio)
The digital IO LDO is a linear regulator that could source 100mA (max) with 2.8V output voltage. It
supplies the the power for baseband circuitry of the SoC. The LDO is optimized for very low quiescent
current and turns on automatically together with Vm/Va LDOs.
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Analog LDO (Va)
The analog LDO is a linear regulator that could source 100mA (max) with 2.8V output voltage.
It supplies the analog sections of the SoC. The LDO is optimized for low frequency ripple rejection in
order to reject the ripple coming from the burst at 217Hz of RF power amplifier.
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TCXO LDO (Vtcxo)
The TCXO LDO is a linear regulator that could source 20mA (max) with 2.8V output voltage.
It supplies the temperature compensated crystal oscillator, which needs ultra low noise supply
with very good ripple rejection.
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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
2.8V, 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.
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Memory LDO (Vm)
The memory LDO is a linear regulator that could source 200mA (max) with 1.8V or 2.8V output voltage
selection based on the supply specification of memory chips. It supplies the memory circuitry in the
handset. The LDO is optimized for very low quiescent current with wide output loading range.
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SIM LDO (Vsim)
The SIM LDO is a linear regulator that could source 80mA (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.
