Quectel M35 User Manual

GSM/GPRS Module Series
M35 User Manual
M35_User_Manual Confidential / Released 45 / 85
AIN1 and AIN2 can be used for input of microphone and line. An electret microphone is usually used.
AIN1 and AIN2 are both differential input channels.
AOUT1 is used for output of the receiver. This channel is typically used for a receiver built into a handset.
AOUT1 channel is a differential channel. If it is used as a speaker, an amplifier should be employed.
AOUT2 is used for loudspeaker output as it embedded an amplifier of class AB whose maximum drive
power is 870mW. AOUT2 is a differential channel.
AOUT2 also can be used for output of earphone, which can be used as a single-ended channel.
LOUDSPKP and AGND can establish a pseudo differential mode.
All of these two audio channels support voice and ringtone output, and so on, and can be switched by
―AT+QAUDCH‖ command. For more details, please refer to the document [1].
Use AT command ―AT+QAUDCH‖ to select audio channel:
 0--AIN1/AOUT1, the default value is 0.
 1--AIN2/AOUT2, this channel is always used for earphone.
 2--AIN2/AOUT2, this channel is always used for loudspeaker.
For each channel, you can use AT+QMIC to adjust the input gain level of microphone. You can also use
―AT+CLVL‖ to adjust the output gain level of receiver and speaker. ―AT+QSIDET‖ is used to set the
side-tone gain level. For more details, please refer to the document [1].
Table 10: AOUT2 Output Characteristics
MIC2P
2
Channel 2 Microphone positive input
MIC2N
3
Channel 2 Microphone negative input
LOUDSPKP
9
Channel 2 Audio positive output
LOUDSPKN
8
Channel 2 Audio negative output
Item
Condition
Min.
Type
Max.
Unit
RMS Power
8ohm load
VBAT=4.2v
THD+N=1%
870
mW
8ohm load
VBAT=3.3v
THD+N=1%
530
mW

Quectel M35 Specifications

General

Brand	Quectel
Model	M35
Category	Control Unit
Language	English