FLY SP-770, Как в инструкции

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3.4.3 Digital IO LDO (Vio)
The digital IO LDO is a regulator that could source 100mA (max) with 2.8V output
voltage. It supplies the baseband circuitry in the handset. The LDO is optimized for
very low quiescent current and will power up at the same time as the digital core LDO.
3.4.4 Analog LDO ( Va )
The analog LDO is a regulator that could source 150mA (max) with 2.8V output voltage.
It supplies the analog sections of the baseband chipsets. The LDO is optimized for low
frequency ripple rejection in order to reject the ripple coming from the RF power
amplifier burst frequency at 217Hz.
3.4.5 TCXO LDO (Vtcxo)
The TCXO LDO is a regulator that could source 20mA (max) with 2.8V output voltage.
It supplies the temperature compensated crystal oscillator, which needs its own ultra
low noise supply and very good ripple rejection ratio.
3.4.6 RTC LDO (Vrtc)
The RTC LDO is a regulator that could source 200µA (max) with 1.5V output voltage. It
charges up a capacitor-type backup coin cell to run the real-time clock module. The
LDO features the reverse current protection and is optimized for ultra low quiescent
current since it is always on except battery voltage below 2.5V.
3.4.7 Memory LDO (Vm)
The memory LDO is a regulator that could source 150mA (max) with 1.8V or 2.8V
output voltage selection based on the supply specs of memory chips. It supplies the
memory circuitry in the handset. The LDO is optimized for very low quiescent current
and will power up at the same time as the digital core LDO.
3.4.8 SIM LDO (Vsim)
The SIM LDO is a regulator that could source 20mA (max) with 1.8V or 3.0V output
voltage selection based on the supply specs of subscriber identity modules (SIM) card.
It supplies the SIMs in the handset. The LDO is controlled independently of the others
LDO.
3.4.9 Reference Voltage Output (Vref)
The reference voltage output is a low noise, high PSRR and high precision reference
with a guaranteed accuracy of 1.5% over temperature. It is used as system reference
in MT6305 internally. However for accurate specs of every LDO output voltage, avoid
loading the reference voltage and bypass it to GND with 100 nF minimum.
3.4.10 SIM Card Interface
The SIM card interface circuitry of MT6305 meets all ETSI and IMT-2000 SIM
interface requirements. It provides level shifting needs for low voltage GSM controller
to communicate with either 1.8V or 3V SIM
cards. All SIM cards contain a clock input, a reset input, and a bi-directional data