User's Manual
URD1
– OTL 5696.1–
022
/ 72740 Edition 0.4
HILONC-
3GPS
APPLICATION
NOTE
: Internal charging of backup battery or 10μF capacitor
The value of resistor R depends on the charging current value of the backup battery manufacturer.
3.8.3.
Backup
Battery
Technology
Capacitor batteries do not have the disadvantages of lithium ion rechargeable batteries:
·
Maximum discharge current is generally greater,
·
No need to regulate charge current.
Moreover, this kind of battery is available in the same kind of package as a lithium ion cell and is fully
compatible
from
a
mechanical
perspective.
The
only
disadvantage
is
that
the
capacity
is
significantly
lower
than
a manganese silicon lithium ion battery.
3.9.
USB
The
HILONC-3GPS
module
has
a
set
of
USB_DP
and
USB_DN
bi-directional
differential
USB
data
lines
that
comply with USB 2.0 specifications.
HILONC-3GPS acts as the USB-Slave and the customer application acts as the USB-Master.
·
In
tegrated high-speed USB PHY.
·
In compliance with USB 2.0 specifications for a peripheral device.
·The
USB
2.0
specification
requires
hosts
such
as
PCs
to
support
all
three
USB
speeds,
namely
low
-speed
(1.5
Mbps),
full-speed
(12
Mbps)
and
high-speed
(480
Mbps).
The
USB
2.0
specification
allows
peripheral
devices
to
support any one or more of these speeds.
The USB_DP and USB_DN signals are routed as a ~90 Ω differential pair. These signals must be routed
side by side and on the same layer and their trace length should be matched as closely as possible.
A 2pF capacitor is required to be installed between USB_DP and USB_DN close to the HILONC-3GPS.
These
signals
have
relatively
fast
edges,
so
they
should
be
routed
away
from
sensitive
circuits
and
signals
such
as
19.2
MHz
TCXO,
sleep
XTAL,
and
RF.
Therefore,
avoid
routing
these
signals
on
surface
layers;
routing
in the inner layer sandwiched between power and ground is preferable.
4.
Power
Management
The host system should supply 3.4V~4.2V to VBAT for powering the baseband, logics circuit and RF circuit.
4.1.
Power
Modes
Depending on the status of the HILONC-3GPS, different power consumption modes can be identified.
Active mode (Active communication)
All
systems
on
HILONC-3GPS
are
active.
In
this
mode,
the
module
is
registered
to
the
network
and
a
voice/data
Note d’étude / Technical document :
01/08/20111
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