SEPTENTRIO mosaic Series, Руководство по оборудованию

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Pinout and I/O Description
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4.1 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 4.12.
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 4.7.
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
4.8.
The module can also control an external power switch, to enable standby mode. See
section 4.12 for details.
See also the power state diagram in section 5.4.
4.2 Antenna(s)
4.2.1 Main Antenna
The main antenna (which is the only antenna on single-antenna modules) is directly
connected to the ANT_1 pad. The ANT_1 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 10
ms. It will periodically retry to switch on the antenna supply until the overcurrent
condition has disappeared.
Pin Name Type Level Description Comment
ANT_1
RF RF input for main antenna
VANT P,I 3 – 5.5V DC supply to the ANT_1 antenna. Max current 150mA. DC supply
is turned off if overcurrent is detected.
If those pads are not connected or if they are tied to GND, there
is no DC voltage at the ANT_1 pad. The two VANT pads should be tied
together.