GSM/GPRS Modules
GSM Module Audio Design Guide
GSM Module Audo Design Guide Confidential/Release 6 / 35
Figure Index
FIGURE 1:MICROPHONE REFERENCE CIRCUIT FOR AIN1&AIN2 ........................................................... 10
FIGURE 2: RECEIVER REFERENCE CIRCUIT FOR AOUT1 .......................................................................... 11
FIGURE 3: RECEIVER REFERENCE CIRCUIT WITH AUDIO POWER AMPLIFIER FOR AOUT1 ................. 11
FIGURE 4:SPK REFERENCE CIRCUIT FOR AOUT2 ................................................................................... 12
FIGURE 5:RECEIVER REFERENCE CIRCUIT WITH AUDIO POWER AMPLIFIER FOR AOUT2 .............. 12
FIGURE 6:HEADSET REFERENCE CIRCUIT............................................................................................... 13
FIGURE 7:MICROPHONE REFERENCE CIRCUIT FOR AIN1&AIN2 ........................................................... 13
FIGURE 8:RECEIVER REFERENCE CIRCUIT FOR AOUT1 ........................................................................ 14
FIGURE 9:HEADSET REFERENCE CIRCUIT............................................................................................... 14
FIGURE 10:SPK REFERENCE CIRCUIT ...................................................................................................... 15
FIGURE 11:MICROPHONE REFERENCE CIRCUIT FOR AIN1&AIN2 ......................................................... 16
FIGURE 12:RECEIVER REFERENCE CIRCUIT FOR AOUT1 ...................................................................... 16
FIGURE 13:SPK REFERENCE CIRCUIT FOR AOUT2 ................................................................................. 17
FIGURE 14:SPK REFERENCE CIRCUIT WITH AUDIO POWER AMPLIFIER FOR AOUT2 ........................ 17
FIGURE 15:HEADSET REFERENCE CIRCUIT............................................................................................. 18
FIGURE 16:SPK REFERENCE CIRCUIT ...................................................................................................... 18
FIGURE 17:HANDS-FREE REFERENCE CIRCUIT AT CHANNEL AIN1/AOUT1 ......................................... 20
FIGURE 18:LAYOUT OF AUDIO .................................................................................................................... 21
FIGURE 19:FIVE ECHO PATHS ..................................................................................................................... 22
FIGURE 20:MICROPHONE SOCKET DESIGN ............................................................................................. 23
FIGURE 22:SPK FREQUENCY RESPONSE................................................................................................. 25
FIGURE 23:SPK THD ..................................................................................................................................... 26