LG -A258 Service Manual page 58

3. TECHNICAL BRIEF
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 earpiece and works in differential. The two single ended headset
drivers can be used to drive a 16 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 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.
Figure 3.14.3 Switching for R/L DACs onto Buffers
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