Table of Contents
Advertisement
"GNSS data ready" and "GNSS RTC sharing" functions are not supported by all u-blox GNSS
receivers HW or ROM/FW versions. Refer to the
the
Hardware Integration Manual
Figure 55Figure 55
illustrates an application circuit for SARA-G350 connection to a u-blox 1.8 V GNSS
receiver:
The SDA and SCL pins of the SARA-G350 module are directly connected to the related pins of the
u-blox 1.8 V GNSS receiver, with appropriate pull-up resistors.
The GPIO3 and GPIO4 pins are directly connected respectively to TXD1 and EXTINT0 pins of the u-
blox 1.8 V GNSS receiver providing "GNSS data ready" and "GNSS RTC sharing" functions.
The GPIO2 pin is connected to the active-high enable pin of the voltage regulator that supplies the
u-blox 1.8 V GNSS receiver providing the "GNSS supply enable" function. A pull-down resistor is
provided to avoid a switch on of the positioning receiver when the SARA-G350 module is switched off
or in the reset state.
The V_BCKP supply output of the SARA-G350 wireless module is connected to the V_BCKP backup
supply input pin of the GNSS receiver to provide the supply for the GNSS real time clock and backup
RAM when the VCC supply of the wireless module is within its operating range and the VCC supply
of the GNSS receiver is disabled. This enables the u-blox GNSS receiver to recover from a power
breakdown with either a Hot-start or a Warm-start (depending on the actual duration of the GNSS
VCC outage) and to maintain the configuration settings saved in the backup RAM.
u-blox GNSS
1.8 V receiver
V_BCKP
1V8
VCC
1V8
1V8
R1
SDA2
SCL2
TxD1
EXTINT0
2
Figure 55: DDC (I
C) application circuit for u-blox 1.8 V GNSS receiver
Reference
Description
R1, R2
4.7 kΩ Resistor 0402 5% 0.1 W
R3
47 kΩ Resistor 0402 5% 0.1 W
U1
Voltage Regulator for GNSS receiver
2
Table 31: Components for DDC (I
C) application circuit for u-blox 1.8 V GNSS receiver
UBX-13000995 - R06
GNSS Implementation Application Note
of the u-blox GNSS receivers for the supported features.
2
GNSS LDO
VMAIN
Regulator
OUT
IN
SHDN
23
C1
GND
R3
U1
R2
26
27
24
25
Part Number - Manufacturer
RC0402JR-074K7L - Yageo Phycomp
RC0402JR-0747KL - Yageo Phycomp
See GNSS receiver Hardware Integration Manual
Objective Specification
SARA-G3 series - System Integration Manual
SARA-G350
V_BCKP
GPIO2
SDA
SCL
GPIO3
GPIO4
[21] or to
Design-in
Page 137 of 218
Advertisement
Table of Contents
