SAM-M8Q - Hardware Integration Manual
UBX-16018358 - R05
Production Information
Hardware description
Page 5 of 23
1
Hardware description
1.1
Overview
The SAM
‑
M8Q module is a concurrent GNSS patch antenna module featuring the high performance u-blox M8
GNSS engine with reception of GPS, GLONASS, Galileo and QZSS signals. Available in an LGA package, it is easy
to integrate and combines exceptional positioning performance with highly flexible power, design, and
connectivity options. SMT pads allow fully automated assembly with standard pick & place and reflow-soldering
equipment for cost-efficient, high-volume production enabling short time-to-market.
For product features see the
SAM-M8Q Data Sheet
[1].
To determine which u-blox product best meets your needs, see the product selector tables on the u-blox
website (www.u-blox.com).
1.2
Configuration
The configuration settings can be modified using UBX protocol configuration messages; see the
u-blox 8 / u-blox
M8 Receiver Description Including Protocol Specification
[2]
.
The modified settings remain effective until power-
down or reset. If these settings have been stored in BBR (Battery Backed RAM), then the modified configuration
will be retained, as long as the backup battery supply is not interrupted.
1.3
Connecting power
The SAM
‑
M8Q antenna module has three power supply pins:
VCC, VCC_IO and V_BCKP
.
VCC: Main supply voltage
The
VCC
pin provides the main supply voltage. During operation, the current drawn by the module can vary by
some orders of magnitude, especially if enabling low-power operation modes. For this reason, it is important
that the supply circuitry be able to support the peak power for a short time (see the
SAM-M8Q Data Sheet
[1]
for specification).
When switching from backup mode to normal operation or at start-up, the SAM
‑
M8Q antenna module
must charge its internal capacitors in the core domain. In certain situations, this can result in a significant
current draw. For low power applications using power save and backup modes, it is important that the
power supply or low ESR capacitors at the module input can deliver this current/charge.
Use a proper GND concept. Do not use any series resistors, ferrite beads or coils in the power line.
The equipment must be supplied by an external limited power source in compliance with the clause 2.5 of
the standard IEC 60950-1.
VCC_IO: IO supply voltage
VCC_IO
from the host system supplies the digital I/Os. The wide range of
VCC_IO
allows seamless interfacing to
standard logic voltage levels independent of the
VCC
voltage level. In many applications,
VCC_IO
is simply
connected to the main supply voltage.
Without a
VCC_IO
supply, the system will remain in reset state.
V_BCKP: Backup supply voltage
In case of a power failure on the module supply,
V_BCKP
supplies the real-time clock (RTC) and battery backed
RAM (BBR). Use of valid time and the GNSS orbit data at start-up will improve the GNSS performance, i.e. hot
starts and warm starts. If no backup battery is connected, the module performs a cold start at power-up.
