Motorola Moto X Pure Edition, Руководства по устранению неисправностей

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Moto X Pure Edition/Moto X Style
Baseband TROUBLESHOOTING GUIDES
MOTOROLA CONFIDENTIAL
Bottom Speaker Circuit
- Inspect the physical placement of U6454 and its related components on main PCB.
(See schematic in previous slides)
- Inspect the “Loudspeaker/Earpiece (Bottom)” components on the main PCB. (See
schematic in the previous slides)
- Verify that B_PLUS voltage is present on the LS_BOOST node, the junction of C6471
and C6474.
- Connect an 8 Ω speaker to contacts M4681 and M4682 with short, thick wires. While
playing audio at normal to high volume, use an oscilloscope to verify that the voltage
on the VBST_AUD_AMP_R node, the junction of C6473 and C6475, alternates
between B_PLUS voltage and approximately 9 V, depending on the audio content.
- While playing media audio at normal to high volume, use an oscilloscope measure the
differential voltage on the test speaker. A 384 kHz PWM waveform should be
observed, similar to the example shown on the previous slide. The waveform
amplitude should vary between 2 x B_PLUS up to 18 V p-p depending on the audio
content.