6-1-4 RF Interface Part
CDMA, FM DATA INTERFACE
•I_OUT, I_OUT_N, Q_OUT, Q_OUT_N: TX analog
signal used during both CDMA and FM mode.
•C_RX_IDATA0-3 and C_RX_QDATA0-3: RX data
bus used during CDMA mode.
•FM_RX_IDATA and FM_RX_QDATA: RX data bus
used during FM mode.
CLOCK
TCXO_CLK: Reference clock used for generation of
CHIPX8. OSC141 : 32.768KHz sleep crystal. Clock
used during SLEEP.
ADC INTERFACE
Eight HK ADC are internally placed in the MSM.
These ADCs are used to read battery voltage,
battery typeand temperature.
RF INTERFACE
TX: TX_AGC_ADJ port is used to control the TX
power level and PA_ON signal is used to
control the power amplifier.
RX: RX_AGC_ADJ port is used to control the RX
gain and TRK_LO_ADJ is used to compensate
the TCXO module.
6-1-5 Audio Part
Internal CODEC in the MSM contains software
controlled amplifier for both the receiving and
transmitting sections. Also, the vocoding schemes
used will be 13kbps QCELP or 8K EVRC. Both
QCELP and EVRC vocoding are performed by the
MSM.
DIGITAL FM BLOCK
The digital FM processor is included in the Mobile
Station Modem(MSM) and brief descriptions of
each block are as follows :
FM TRANSMIT PROCESSOR
Pre-Emphasis Circuit
This part fe6dB/oct to reduce signal loss
and noise in Tx path.
Compressor
The compressor features 2:1 level compressor to
reduce signal loss and noise in Tx path. The zero
crossing level of the compressor is ±2.9 kHz/dev,
attack time is 3mS, and release time is 13.5mS.
Limiter
The limiter performs to cut ±0.53 Vp-p or higher
audio signal level so that the FM frequency
deviation is not over ±12 kHz/dev. The function is
used to avoid confusion over phone line. LPF is
used to reduce a specific high frequency of limited
signal.
SAMSUNG Proprietary-Contents may change without notice
6-3
Circuit Description
