TIM-5H
-
Hardware
Integration
Manual
Design-In
GPS.G5-MS5-07015-A-1
u-blox
proprietary
Page 26
your position is our focus
GND
RF_IN
GND
V_ANT
VCC_RF
Active Antenna
ADDET_N
V_ANT
Antenna
Supply in
Analog GND
R1
R2
R3
R4
R5
T2
PNP
T1
PNP
C1
C2
FB1
AADET_N
TIM-5H
Figure 16: Schematic of open circuit detection
References
Value
Tolerance
Description
Remarks
C1
2.2
μ
F
±
10%
Capacitor,
X7R,
min
10
V
C2
100
nF
±
10%
Capacitor,
X7R,
min
10
V
FB1
600
Ω
Ferrite
Bead
e.g.
Murata
BLM18HD601SN1
R1
15
Ω
±
10%
Resistor,
min
0.063
W
R2
10
Ω
±
10%
Resistor,
min
0.250
W
R3,
R4
10
k
Ω
±
10%
Resistor,
min
0.063
W
R5
33
k
Ω
±
10%
Resistor,
min
0.063
W
T1,
T2
PNP
Transistor
BC856B
e.g.
Philips
Semiconductors
Table 5: Active Antenna Supervisor, bill of material
Firmware
supports
an
active
antenna
supervisor
circuit,
which
is
connected
to
the
pin
AADET_N
.
An
example
of
an
open
circuit
detection
circuit
is
shown
in
High
on
AADET_N
means
that
an
external
antenna
is
not
connected.
Short Circuit Detection (SCD)
A
short
circuit
in
the
active
antenna
pulls
V_ANT
to
ground.
This
is
detected
inside
the
u-blox
5
module
and
the
antenna
supply
voltage
will
be
immediately
shut
down.
Antenna
short
detection
(SCD)
and
control
is
enabled
by
default.
1
Transistors
from
other
suppliers
with
comparable
electrical
characteristics
may
be
used.
