SIM900D Hardware Design
3.10.1 Speaker Interface Configuration
SPK1P
SPK1N
10pF
10pF
10pF
33pF
33pF
Close to speaker
GND
GND
Differential layout
33pF
ESD
ANTI
ESD
ANTI
MODULE
Figure20: Speaker interface configuration
MODULE
SPK2P
SPK2N
Differential layout
Amplifier
Circuit
10pF
10pF
33p
F
33pF
33pF
Close to speaker
GND
GND
1
0
.
0
4
2
9
10pF
ESD
ANTI
ESD
ANTI
Figure21: Speaker interface with amplifier configuration
SIM900D_HD_V1.02
09.04.2010
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