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V1.03 subject to changes | Webdyn © by Flexitron Group
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Besides all resources embedded on LTE module, main board includes additionally the following items:
• eMMC memory for system software needs.
• RTC to provide current date and time for system logs. In case of power supply is lost, a Super-
Capacitor acts as energy backup to keep RTC running.
•
USB connector with required filtering and protection elements. This interface is intended to be
used for factory test and system configuration purposes.
•
RS232 transceiver with required filtering and protection elements.
•
RS485 transceiver with required filtering and protection elements. Termination resistor
(120ohm) is connected on receive differential pair as well as true fail-safe biasing resistors,
referenced to 3.3V.
• RJ45 connector as external interface for RS232 and RS485 signals.
• SIM card socket.
•
U.FL type RF connector to attach u.FL-SMA pigtail. SMA connector is fixed to connectors panel.
• BOOT jumper. Used only for Factory programming purposes.
• TEST jumper. Used only for Factory testing purposes.
• LEDs. Four Leds are included to inform about system operating status.
•
PMC. Power Management Controller based on a microcontroller with following tasks:
• Manages power-on power-off sequence of LTE module as required.
• Act as a hardware watchdog system supervisor to guaranty proper operation.
• Communicates to LTE module to set / get data for system operation and maintenance.
• Reset switch causes PMC power-off, hence, full system power-off. After Reset switch is
released, PMC is powered on again and starts power-up sequence of whole system.
Regarding power supply operation, internal AC-DC module sources main +5V power supply when external
power supply is available. A Super-Capacitor is included as backup source energy when external power
supply disappears to provide required energy to system, in order to send a trap remotely to inform that
main power energy is lost. Super-Capacitor requires a charger to control charging, as long as mains
power input is available.
