LG -T370 Service Manual page 54

Digital-to-analog converters
The multi-bit oversampling DACs of the X-GOLD™215 audio front-end convert the 16-bit data words coming
from the digital interpolation filters to analogue signals.
Output Amplifier
The different output buffers in X-GOLD™215 are driven by the outputs of the selection block. The differential
earpiece driver can be used to drive a 16 Ω earpiece and works in differential. The two single ended headset
drivers can be used to drive a 16 Ω headset. They can work unipolar mode, where an AC coupling of the headset
might be needed, or can work also in bipolor mode. The differential loudspeaker driver can be used to drive a 8 Ω
loudspeaker. As it is a class-D amplifier the needed suppression of the higher harmonics of the switching signals
has to be achieved by the external circuitry. The buffers are designed to be short circuit protected.
LGE Internal Use Only
Figure 3.12.3 Switching for R/L DACs onto Buffers
Figure 3.12.3 Switching for R/L DACs onto Buffers
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3. TECHNICAL BRIEF
3. TECHNICAL BRIEF
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