SARA-G3 series - System Integration Manual
UBX-13000995 - R06
Objective Specification
Design-in
Page 91 of 218
2
Design-in
For an optimal integration of SARA-G3 modules in the final application board follow the design guidelines
stated in this section.
Every application circuit must be properly designed to guarantee the correct functionality of the related
interface, however a number of points require high attention during the design of the application device.
The following list provides a ranking of importance in the application design, starting from the highest
relevance:
1.
Module antenna connection:
ANT
and
ANT_DET
pins. Antenna circuit directly affects the RF
compliance of the device integrating SARA-G3 module with applicable certification schemes. Very
carefully follow the suggestions provided in section
for schematic and layout design.
2.
Module supply:
VCC
and
GND
pins. The supply circuit affects the RF compliance of the device
integrating SARA-G3 module with applicable required certification schemes as well as antenna circuit
design. Very carefully follow the suggestions provided in section
design.
3.
SIM card interface:
VSIM
,
SIM_CLK
,
SIM_IO
,
SIM_RST
,
SIM_DET
pins. Accurate design is required
to guarantee SIM card functionality reducing the risk of RF coupling. Carefully follow the suggestions
provided in section 2.4 for schematic and layout design.
4.
System functions:
RESET_N
,
PWR_ON
pins. Accurate design is required to guarantee that the voltage
level is well defined during operation. Carefully follow the suggestions provided in section 2.2 for
schematic and layout design.
5.
Analog audio interface:
MIC_BIAS
,
MIC_GND
,
MIC_P
,
MIC_N
uplink and
SPK_P
,
SPK_N
downlink
pins. Accurate design is required to obtain clear and high quality audio reducing the risk of noise from
audio lines due to both supply burst noise coupling and RF detection. Carefully follow the suggestions
provided in section 2.6.1 for schematic and layout design.
6.
32 kHz signal: the
EXT32K
input pin and the
32K_OUT
output pin of SARA-G300 and SARA-G310
modules require accurate layout design as it may affect the stability of the RTC timing reference.
Carefully follow the suggestions provided in section 2.2.3 for schematic and layout design.
7.
Other digital interfaces: UART and auxiliary UART interfaces, DDC I
2
C-compatible interface, digital
audio interface and GPIOs. Accurate design is required to guarantee proper functionality. Follow the
suggestions provided in sections 2.5.1, 2.5.2, 2.5.3, 2.6.2 and 2.7 for schematic and layout design.
8.
Other supplies: the
V_BCKP
RTC supply input/output and the
V_INT
digital interfaces supply output.
Accurate design is required to guarantee proper functionality. Follow the suggestions provided in
sections 2.1.2 and 2.1.3 for schematic and layout design.
Formatted:
English (U.S.)
Formatted:
English (U.S.)
