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SAMSUNG Proprietary-Contents may change without notice
6-8
STH-N375
Circuit Description & Circuit Diagrams
2-5. Radio component control
U101 monitors the state of the radio part, and delivers the information to U203. Then, U203 sends the
proper control signals to radio relating regulators and AGCs. The radio interface signals are summarized in
the Table 2-2.
Table 2-2. Radio Interface Signals
Signal Name
Source/Destination
Function
PON_LD
BEC/RFIC
Limiter/Discriminator power control
TX_RFBAND
BEC/IF VCO
Tx band control (0=PCS, 1=Cell)
VCTCXO_IN
TCXO/BEC
14.4 MHz clock
VCTCXO_PC
BEC/TCXO
14.4 MHz clock power control
PLL_DATA
BEC/RFIC
PLL serial data
PLL_CLK
BEC/RFIC
PLL serial clock
PLL_STRB1
BEC/RFIC
PLL serial strobe
RF_BAND
BEC/Various
Cell/PCS band select (0=Cell, 1=PCS)
PREAMP_G
BEC/Regulator
Rx AGC Gain step
RX_BAT
BEC/RFIC & Various
Receiver power control
TX_BAT
BEC/RFIC & Various
Transmitter power control
ANALOG_DIG
BEC/Various
Band control (0=Analog, 1=Digital)
LOCK_DET
RFIC/BEC
PLL lock detect status
PLL_ON
BEC/Regulator
PLL power control(V_RF1:RFIC)
A_IF_IN
RFIC/IFC
IF comparator input
RX_Q, RX_QN
RFIC/IFC
Differential analog receive Q channel
RX_I, RX_IN
RFIC/IFC
Differential analog receive I channel
TX_Q, TX_QN
IFC/RFIC
Differential analog transmit Q channel
TX_I, TX_IN
IFC/RFIC
Differential analog transmit I channel
MOD
IFC/RFIC
Drive to modulator
TX_PWR
Detector/IFC
Tx power detector
RSSI
RFIC/IFC
Rx Signal Strength Indicator
AFC_OUT
IFC/VCTCXO
Auto Frequency Control voltage
AGC_OUT
IFC/RFIC
Auto Gain Control voltage
PA_CNT
IFC/RFIC
Power Amplifier control voltage
DEMOD
RFIC/IFC
Discriminator output
TXDA_REF
RFIC/IFC
Tx section common mode DC bias
PON_TX
BEC/Regulator
TX up converter power (V_RF2:RFIC)
PON_VRF3
BEC/Regulator
Local Amp power(V_RF3:RFIC)