SimCom SIM5300E Hardware Design

SIM5300E_Hardware_Design_V1.02
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TXD
RXD
GND
PWRKEY
Debug port
I/O connector
DBG_RXD
DBG_TXD
GND
PWRKEY
MODULE
Figure 23: Connection for software upgrading and debugging
The serial port and the debug port support the CMOS level. If user connects the module to the computer,
the level shifter should be added between the DCE and DTE (like Figure 21).
4.7 AUDIO INTERFACES
SIM5300EA provides one analog input, which could be used for electric microphone. The module also
provides one analog output. The output can directly drive 32Ω receiver.
AT command “AT+CMIC” is used to adjust the input gain level of microphone. AT command “AT+SIDET” is
used to set the side-tone level. In addition, AT command “AT+CLVL” is used to adjust the output gain level.
For more details, please refer to document [1]
In order to improve audio performance, the following reference circuits are recommended. The audio signals
have to be layout according to differential signal layout rules as shown in following figures. If user needs to
use an amplifier circuit for audio, National Semiconductor Company’s LM4890 is recommended.
Note: Only SIM5300EA support Audio Function.
4.7.1 Speaker Interface Configuration
SPK_P
SPK_N
10pF
10pF
10pF
33pF
33pF
33pF
ESD
ANTI
ESD
ANTI
MODULE
The lines in bold type should
be accorded to differential
signal layout rules
These components should
be placed to speaker as
close as possible
Figure 24: Speaker reference circuit

SimCom SIM5300E Specifications

General

Brand	SimCom
Model	SIM5300E
Category	Control Unit
Language	English