Nokia 9000i Service Manual page 58

RAE/RAK–1N
Baseband
AUDIO
Introduction
The AUDIO block contains an audio codec and a booster amplifier
together with some peripheral components. The codec contains
microphone and earpiece amplifiers and all the necessary switches for
routing. The codec is controlled by the MCU. The PCM data comes from
and goes to the DSP. The booster amplifier for the Personal Hands–Free
(PHF) is connected to one of the codec's outputs. Physically the codec
resides in MCM2 while the other parts are assembled on the CMT
motherboard.
Technical specification
Table 34. External Signals and Connections, Inputs
Signal Name
VA1 Analog supply voltage. Max 40 mA.
VA3 Analog supply voltage for the PHF power amplifier. Max 200
mA.
PCMIN Received audio in PCM format
SYNC 8kHz codec frame sync
CODEC_CLK 512kHz codec main clock
PCMCDI Audio codec control data
PCMCLK Clock for audio codec control data transfer
XSELPCMC Audio codec chip select
AMP_PWR PHF power amplifier control
MICN, MICP Differential handportable microphone signal
EXTMIC External microphone signal
PHFMICN, Differential Personal Hands–Free microphone signal
PHFMICP
Table 35. External Signals and Connections, Outputs
Signal Name
PCMOUT Transmitted audio in PCM–format
PCMCDO Audio codec control data
JCONN Junction box connected signal (multiplexed with EXTMIC)
EARN, EARP Received audio to the earphone, differential signal
EXTEAR Received audio to the external accessories
PHFEARN, Received audio to the Personal Hands–Free speaker,
PHFEARP differential signal
Page 2–32
Signal description
Signal description
After Sales
Technical Documentation
From
PWRU
PWRU
DSPU
ASIC
ASIC
CTRLU
CTRLU
CTRLU
CTRLU
SIM Conn
B2B Conn
B2B Conn
To
DSPU
CTRLU
CTRLU
SIMFLEX
Conn
B2B Conn
PHF Conn
Original, 08/96