Audio Interface - LG KP105 Service Manual

3.10 Audio Interface

LOUD2
LOUD1
VMIC
MICP2
MICN2
MICP1
MICN1
EPPA1
EPP1
EPN1
The audio front-end of E-GOLDvoice offers the digital and analog circuit blocks for both receive and
transmit audio operation and ringing. It features a high-quality, digital-to-analog path with amplifying
stages for connecting acoustic transducers to the E-GOLDvoice. In the transmit direction the supply
voltage generation for microphones, low-noise amplifier and analog to digital conversion are integrated
on the E-GOLDvoice.
For E-GOLDvoice the EPp1/EPn1 driver are used as differntial Earpiece-Driver, EPPa1 is used as
single-ended Headset-Driver.
The audio front-end itself can be considered to be organized in three sub-blocks:
• Interface to processor cores (TEAKlite and - indirectly - C166S)
• Digital filters
• Analog part.
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
K14
L15
P12
P11
R12
P15
R13
M14
M12
N15
Figure 3-10-1 Audio interface
- 33 -
3. TECHNICAL BRIEF
VMIC
SPK_N
SPK_P
HS_MIC_P
C127
HS_MIC_N
1000p
MIC_P
MIC_N
HS_REC
REC_P
REC_N
LGE Internal Use Only