Audio; Electrical Interface Between Baseband And Audio Components - Nokia RM-497 Service Manual

RM-497
System Module

Electrical Interface Between Baseband and Audio Components

Introduction
The D2800 JUNO (BCM21351) BB ASIC has interfaces for an internal and external microphone, earpiece drivers,
stereo headset drivers, and mono internal hands-free drivers. It also has an Accessory Component Interface
(ACI) interface to identify peripherals plugged into the 3.5mm AV jack. Two GPIO pins are used for detecting
when a plug is inserted into the X2001 AV connector and another is used for enabling the stereo headset
amplifier.
The AVI signals are referenced to 2.5V. All three GPIO pins use 1.8V CMOS signaling levels.
D2800 Baseband ASIC (BCM21351) Audio Interface Pins
Pin Name
ARXMICP1 T22
ARXMICN1 R22
ARXMICBI U22
AS
ACI_DATA Y23
ACI_AUDIO W22
IN
GPIO30 V17
GPIO14 R4
ARXMICP2 R23
ARXMICN2 T23
ARXAUXMI U23
CBIAS
GPIO22 V2
DDACAMP V12
LP100A
DDACAMP U12
LN100A
DDACAMP U13
RP100A
DDACAMP V13
RN100A
DDACAMP Y12
LP100B
DDACAMP W12
LN100B
IHFAMPRP AB21
LINOUT
Issue 1

Audio

Pin
COMPANY CONFIDENTIAL
Copyright © 2010 Nokia. All rights reserved.
I/O Type
I Analog Internal MIC Input +
I Analog Internal MIC Input -
Out Analog Internal MIC Bias
put
I/O Analog ACI Data Input/Output
I Analog ACI MIC bias point
I/O CMOS Plug Detect
I/O CMOS Connect Detect
I Analog External MIC Input +
I Analog External MIC Input -
Out Analog External MIC Bias
put
I/O CMOS Headset Amplifier Enable
O Analog External Headset Left
Driver +
O Analog External Headset Left
Driver -
O Analog External Headset Right
Driver +
O Analog External Headset Right
Driver -
O Analog Earpiece Driver +
O Analog Earpiece Driver -
O Analog Internal Hands-free driver
+
Description
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