M16 EVB User Guide
3.2. Audio interface
Figure 4: Audio interface
Table 4: Pins of audio channel 1
Pin
Signal
I/O
Description
1
MIC1N
I
Negative microphone input
2
SPK1N
O
Negative receiver output
3
SPK1P
O
Positive receiver output
4
MIC1P
I
Positive microphone input
Table 5: Pins of audio channel 2
Pin
Signal
I/O
Description
1
MIC2N
I
Negative microphone input
2
AGND
AGND of audio circuits
3
SPK2P
O
Positive receiver output
4
MIC2P
I
Positive microphone input
A headset or handset can be used in audio channel 2. The headset is included in the EVB kit from
Quectel, while a suitable desktop phone handset can be selected by customer according to the
definition of signal in Table 4.
M16_EVB_UGD_V1.01
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