LG GB220 Service Manual page 56

▪ Digital-to-analog converters
The multi-bit oversampling DACs of the X-GOLD™213 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™213 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 bipolar 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.
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Copyright © 2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
Figure 3.12.3 Switching for R/L DACs onto Buffers
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3. TECHNICAL BRIEF
Copyright © 2007 LG Electronics. Inc. All right reserved.
Only for training and service purposes
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