Audio - LG KF350 Service Manual

3.12 Audio

KF350 Audio signal flow diagram as following diagram.
3.12.1 Audio amplifier
Audio amplifier sub system IC is an audio power amplifier capable of delivering 1.2 W of continuous
average power into a mono 8ߟ load, 50mW per channel of continuous average power into stereo
32Ω ߟ single-ended (SE) loads. The MAX9877 features a 32-step digital volume control and ten
distinct output modes. The digital volume control, output modes (mono/SE/OCL) are programmed
through a two-wire I2C interface that allows flexibility in routing and mixing audio channels.
BB_SND_R
BB_SND_L
FM_SND_R
FM_SND_L
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
BBP
PMB8877
FM
BT+ FM
Figure 16 Audio signal flow diagram
AUDIO_IN
C216
1000p
C215 1u
C217 1u
C218 1u
C219 1u
C220 1u
C222
1u
SDA
SCL
C221 1u
R210 20K
R211 8.2
EAR_P
R212 8.2
EAR_N
Figure 17 Audio amplifier PMIC
3. TECHNICAL BRIEF
MAX
9877
Ear M I C
VBAT
VBAT
C212 2.2u
C213 1u C214 2.2u
A4
C1N
A5 A1
HSO_R
C1P HPR
A2
HSO_L
HPL
D1
INA2
D2
INA1
U201
C1
MAX9877AEWP_TG45
INB2
C2 D5
INB1 OUT+
B2 B5
BIAS OUT-
B3
SDA
C3
SCL
D4
RXIN+
B4
RXIN- C226 C227
27p 27p
- 47 -
MIC
SPK
RCV
SPK_RCV_P
SPK_RCV_N
LGE Internal Use Only