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3. BB Circuit Technical brief
3.13.1 Audio amplifier
use external AMP(LM49150).
GM310
LM49150 combines a high efficiency Class D audio power amplifier with a stereo Class AB capacitor-
less Direct Drive headphone amplifier.
LM49150 delivers up to 725mV from a 3.7V supply into an 8ohm load with 87% efficiency to extend
battery life.
3.13.2 Microphone circuit
LGE Internal Use Only
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[Figure 3.13.1-1] Audio AMP circuit diagram
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[Figure 3.13.2-1] Microphone circuit diagram
- 44 -
GM310f service manual
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Copyright © 2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
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