Smart Machine Smart Decision
geometry/density, and while unassisted, GPS-only solutions typically perform poorly indoors. The
SIM5320J-TE GPS solution provides optimal time to fix, accuracy, sensitivity, availability, and reduced
network utilization in both of these environments, depending on the given condition.
3.12.3
Application Guide
Users can adopt an active antenna or a passive antenna as GPS signal transceiver.
In active antenna circuit, SIM5320J-TE provides DC 2.6V (VREG_AUX) for active antenna.
GPS can be used by NMEA port. User can select NMEA as output through UART or USB. NMEA
sentences are automatic and no command is provided. NMEA sentences include GSV, GGA, RMC, GSA,
and VTG. Before using GPS, user should configure SIM5320J-TE in proper operating mode by AT
command. Please refer to related document for details. SIM5320J-TE can also get position location
information through AT directly.
Note:GPS is closed by default, it could be started by AT+CGPS. The AT command has two parameters, the first is on/off,
and the second is GPS mode. Default mode is standalone mode.
AGPS mode needs more support from the mobile telecommunication network. Refer to AGPS application document for
details.
3.13
Multi-functional interface
SIM5320J-TE merges functions for various applications. It can enrich users’ design and lower the cost of
users’ hardware.
3.13.1
Sink Current Source
The dedicated pin (CURRENT_SINK) is intended for driving passive devices
,
such as LCD backlight, this
implementation is +5V tolerant and suitable for driving white LEDs. The high-current driver can maintain
a constant current which is set by
the AT command “AT+ CLEDITST”
, capable of up to 150 mA.
Table 32: Electronic characteristic
Symbol
Description
Min
Typ
Max
Unit
CURRENT_SINK Input voltage
0.5
VDD
5
V
I
O
Input current
-
-
150
mA
Since the driver is ground-referenced current sink, the operating device it drives must form a current path
between the VDD pin and the CURRENT_SINK pin. The following figure is for users reference.
SIM5320J-TE_Hardware Design_V1.01
2012-11-09
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