11
11
Pinout and I/O Description
11
3.1
Power Supply
The module is powered through the VDD_3V3 pins.
Pin Name
Type
Level
Description
Comment
VDD_3V3
P,I
3.3V +/-5%
Main power supply input
All VDD_3V3 pins must be tied
together.
GND
Gnd
0
Ground
All GND pins must be connected to
ground.
VDD_BAT
P,I
3.3V +/-5%
“Always
-
on” supply.
Must be tied to VDD_3V3 unless an
external power switch is available.
See section 3.12.
nRST_IN
Ctrl,PU
3V3_LVTTL
Reset input, active negative. Module is in reset when low. Short
low pulses of less than 1 µs are ignored.
Internally debounced, can be directly
connected to a push-button.
MODULE_RDY
O
3V3_LVTTL
Level is high when module is operating, and low when in standby
or reset.
Level becomes high about 300
milliseconds
after
powering
/
unresetting the module.
1V8_OUT
P,O
1.8V
1.8V output, see below
SYNC
I
1V8_LVTTL
Reserved. Must always be connected to 1V8_OUT.
Note that the 2V8_OUT and 2V8_IN pins are exclusively reserved to power the internal
TCXO. See section 3.7.
The 1V8_OUT pin is a DC output (120mA max current) which can, for example, be used to
power level-shifters for the 1V8_LVTTL signals (EVENT and PPS), see for example section
3.8.
The module can also control an external power switch, to enable standby mode. See
section 3.12 for details.
3.2
Antenna
The antenna can be directly connected to the ANT pad. The ANT-input is ESD-protected
in the module and carries a DC-voltage to power the antenna, avoiding the need for an
external bias-tee. This DC-voltage is imposed to the module via the VANT-pad.
In case of an overcurrent condition (e.g. short circuit in antenna cable), the module will
first limit the current to about 150 mA and then switch off the antenna supply in about 3
ms. It will periodically retry to switch on the antenna supply until the overcurrent
condition has disappeared.
Refer to 4.4.3 for RF-routing recommendations.
Pin Name
Type
Level
Description
Comment
ANT
RF
RF input
VANT
P,I
3
–
5.5V
DC supply to the antenna. Max current 150mA. DC supply to
antenna is turned off if overcurrent is detected.
If this pin is not connected or if it is tied to GND, there is no DC
voltage to the antenna.
Never inject an external DC voltage into the ANT-pad as it may damage the module. For
instance, when using a splitter to distribute the antenna signal to several GNSS receivers,
make sure that no more than one output of the splitter passes DC. Use DC-blocks
otherwise.
