Level Shifter Description; Block Diagram Of Levelshifter Part - Nokia 616 Service Manual

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HDMUTE Level shifter
The B2BHDMUTEX signal, that is used by the phone engine to activate or deactivate the
HD-Power amplifier is converted here from 1.8V logic level of the engine to 4.2V level
used by the power amplifier. This logic inverts the signal of the control output.
Filter
This part filters the audio signals from EB and mainly cares to close up the symmetric
B2BXEAR lines when JB is standalone without phone engine.

Level shifter Description

Block Diagram of Levelshifter Part

CRM
Issue 2.0 Mar/2005
Company Confidential
Figure 25: HDMute Level shifter Realization
Figure 26: B2BXEAR Filter
Figure 27: Block-Diagram of Level shifter Block
Copyright © 2005 Nokia Corporation.
Company Confidential
TFE-4/RV-1
TF5 Technical Information
To HDSPKR
and HFSPKR
B2BCRM
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