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Only for training and service purposes
LGE Internal Use Only
3. TECHNICAL BRIEF
LGE Internal Use Only
Audio codec operating modes can be controlled by writing 5 bit codes in the AudMode field of the
AudControl1 register and in the AudMode_M field of the AudControl4 register.
AudControl1 programs the sampling rate and stereo or monophonic operating mode for PCM audio
samples input via the ASPORT.
AudControl4 programs the sampling rate and stereo or monophonic operating mode for PCM audio
samples input via the MSPORT. The AudControl1 and AudControl4 contain control bits that allow system
software to turn on three audio loudness enhancement techniques meant for use when driving 8 ohm
loudspeakers. These are high pass filter, dynamic range compressor, and x4 gain boost.
These loudness enhancement techniques can be used with any AudMode or AudMode_M setting. And are
programmed seperately and independently for the ASPORT and MS- PORT PCM audio decoder data streams.
Analog Audio Output & Input Configurations
Output configurations are set by AudOS[4:0] bits in the AudControl2 register. Input configurations are set
by AudIS[3:0] bits in the AudControl2 register.
AudIn3LMute bit high in the AudMuteControl register (0x27 ). For configurations using “DAC2+AIN3R”, the
AIN3R input may be muted by setting AudIn3RMute bit high in the AudMuteControl register. For
configurations using “AIN3(L)”, the AIN3L and AIN3R inputs may be used as a differential input or the AIN3L
input may be used as a single-ended input.
Single ended configuration is chosen by setting AudIn3Cfg bit high in the AudControl3 register (0x32 ).
Audio DACs and Analog Filters
The Audio DACs are over-sampled switched-capacitor DACs. The analog filters are switched-capacitor filters
followed by active-RC filters.
Audio Output 3
PGA gain for Audio Output 3 Stereo Configuration can be set by using bits AudOutL- Gain[4:0] and
AudOutRGain[4:0] in the AudOutLRControl (0x22 ) register. When Audio Output 3 configured as
monophonic differential output PGA gain can be set by using bits AudOut3Gain[4:0] in the AudOut3Control
register (0x23 ).
This port is used for headset speaker in stereo. This port must use DC-coupling capacitor as output DC. It
uses two 100uF capacitor each other in left and right output.