User Guide

PAMS
System Module DB6
NHB–3
Technical Documentation
Original 26/97
Page 4–28
AUDIO
Introduction
The AUDIO block consists of an audio codec with some peripheral compo-
nents. The codec contains microphone and earpiece amplifier and all the nec-
essary switches for routing. The codec is controlled by the MCU. The PCM
coded data comes from and goes to the DSP.
Technical Specification
External Signals and Connections, Inputs
Signal name Signal description From
VA1 Analog supply voltage. Max 40 mA. PWRU
PCMIN Received audio in PCM format DSPU
SYNC 8kHz frame sync ASIC
CODEC_CLK 512kHz codec main clock ASIC
PCMCDI Audio codec control data CTRLU
PCMCLK Clock for audio codec control data CTRLU
transfer
XSELPCMC Audio codec chip select CTRLU
MIC_JCONN External microphone System conn
MICN,MICP Differential microphone signal UIF conn
External Signals and Connections, Outputs
Signal name Signal description To
PCMOUT Transmitted audio in PCM–format DSPU
PCMCDO Audio codec control data CTRLU
MIC_ENA Microphone enable UIF
EAR_HFPWR External received audio System conn
EARN,EARP Internal received audio UIF
JCONN Junction box connected signal CTRLU
(multiplexed with HFMIC)