Audio Interface - Queclink GV200G User Manual

GV200G User Manual

3.5. Audio Interface

There is a differential output for speaker and a signal-ended microphone on GV200G. Please
note that the PIN 1 is analog ground and should not be used as a power ground. GV200G has
an audio amplifier internally, so it can drive a louder speaker directly. It is recommended to
connect an 8 Ohm speaker to speaker interface, and an electret microphone is also
recommended.
Microphone input characteristics
Table 14: The characteristics of Microphone
Parameter
Working Voltage
Working Current
External Microphone Load Resistance
Please note there are some recommendations about microphone:
1: Use an electret microphone with a sensitivity of -42±3dB/Pa @ 2V （not less than -44±3dB）
and impedance of 2.2kΩ.
2: Two filter capacitors (10pF (0603) and 33pF (0603)) are recommended to build into
microphone by vendor. These two capacitors could largely suppress coupling TDD noise
from RF interference.
3: MIC /AGND should be a couple of differential traces, not be close to power supply signals.
TRACGV200GUM001
Figure 18: Example connection for audio
Min Typ Max
1.0 1.5 2.0
200 500
2.2
Unit
V
uA
k Ohm
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