LG GS500 Manual page 44

3. BB CIRCUIT TECHNICAL BRIEF
3.11.1 Audio amplifier 3.12.1 Audio amplifier
GS500 use external AMP(LM49151TLX).
LM49151TLX combines a high efficiency Class D audio power amplifier with a stereo Class AB capacitor-less
Direct Drive headphone amplifier.
LM49151TLX delivers up to 725mW from a 3.7V supply into an 8ohm load with 87% efficiency to extend
battery life.
AUDIO AMP SUB SYSTEM & SIGNAL DISTRIBUTOR
R415 0
C476
RCV_P
R418 0
C477
RCV_N
C469
FM_AUDIO_L
C472
BB_SND_L
C471
BB_SND_R
C470
FM_AUDIO_R
I2C1_SDA
I2C1_SCL
LGE Internal Use Only
VBAT
C424
2V62_VIO C425
0.1u 4.7u
1u
1u
E1
INM+
D1
INM-
1u
220n C1
INL
220n C2
LM49151TLX
INR
1u
C3
BYPASS
A1
I2CVDD
B2
SDA
B3
SCL
C478 C466
2.2u 2.2u
C473
2.2u
[Figure 3.13.1-1] Audio circuit diagram
GS500 service manual
A4
LSOUT+
A3
LSOUT-
D2
SET
U410
E3
HPL
E2
HPR
C437
R407
C475
39p
C467
0.1u
2.2u
100K
R422
EAR_GND
- 46 -
Copyright © 2010 LG Electronics. Inc. All right reserved.
FB405
600
SPK_RCV_P
FB401
600
SPK_RCV_N
FB402
HS_3.5_L
1800
FB403
HS_3.5_R
1800
C438 C465 C468
39p 39p 39p
Only for training and service purposes