Contents
About the document ................................................................................................................................... 2
Contents ....................................................................................................................................................... 3
Table Index ................................................................................................................................................... 5
Figure Index ................................................................................................................................................. 6
1
Introduction .......................................................................................................................................... 7
1.1.
Summary ...................................................................................................................................... 7
1.2.
Safety Information ........................................................................................................................ 7
2
Audio Circuit Design ........................................................................................................................... 9
2.1.
Audio Circuit Reference ............................................................................................................. 10
2.1.1.
M1x ................................................................................................................................. 10
2.1.2.
M95................................................................................................................................. 13
2.1.3.
2.1.4.
M80................................................................................................................................. 16
2.2.
Ringtone ..................................................................................................................................... 19
2.3.
2.4.
2.5.
TDD Noise Solution.................................................................................................................... 21
2.6.
2.7.
Component of SPK .................................................................................................................... 25
2.8.
Component of Microphone......................................................................................................... 26
3
Description and Suggestion ............................................................................................................. 27
3.1.
AT Command ............................................................................................................................. 27
3.1.1.
AT+QAUDCH ................................................................................................................. 27
3.1.2.
How to Modify Volume ................................................................................................... 28
3.1.2.1. AT+QMIC .............................................................................................................. 28
3.1.2.2. AT+CLVL ............................................................................................................... 29
3.1.2.3. AT+QSIDET .......................................................................................................... 30
3.1.3.
Echo Algorithm ............................................................................................................... 31
GSM Module Audo Design Guide
GSM Module Audio Design Guide
Confidential/Release
GSM/GPRS Modules
3 / 35
Need help?
Do you have a question about the GSM Series and is the answer not in the manual?