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4 Electrical Interfaces
The following subsections contain information for the electrical interfaces of the Modem.
4.1 User Host Device
The user host device provides the following connections to the Modem:
● DC power supply input: 3.0V to 5.0V, (1000 mA
peak
at 3.3V)
○ EMI/RFI shielding CAN is
required
if using a switching DC power supply in order
to contain radiated emissions
○ Additional filtering of the power supply is highly recommended
■ See
for best practices
● Data interface
○ 3.3V Serial Data Interface
● Satellite signal (Use the provided U.FL connector labeled VHF)
● GPS signal (Use the provided U.FL connector labeled GPS)
● GPIO1 (optional)
© 2022 SWARM TECHNOLOGIES
SWARM M138 MODEM PRODUCT MANUAL · REV 1.20 · FEBRUARY 2022
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