Venice Single Board Computer Operating Manual
Power Architecture
DC input power is supplied through the barrel jack, one Ethernet connector using
802.3at Power over Ethernet, or the other Ethernet Port connector using Passive Power
over Ethernet.
Barrel Jack Power
The barrel jack at location J16 has a 2.5mm inner pin diameter. The connector is
polarized with the center pin being positive. The input voltage range is 8-60V.
The mating connector is G/S SR2048A, available from Jameco as part number
195038.
802.3at Active Power over Ethernet
One Gigabit Ethernet Port supports 802.3at Power over Ethernet by acting as a
Powered Device (PD) with power being supplied by Power Sourcing Equipment
(PSE) such as an 802.3at compliant Ethernet switch. This includes providing
detection signature, classification signature, and current inrush limiting after
being instructed to power on. The input voltage range is 36-57V as defined by
the PoE specification. The power and ground connections include full wave
bridge rectification so that they can be connected on any two data pairs.
More PoE information is available on the Gateworks wiki here:
http://trac.gateworks.com/wiki/poe
Passive Power over Ethernet
One RJ45 Ethernet jack supports Passive Power over Ethernet. This
configuration is most useful for powering the SBC through an Ethernet jack
without an 802.3at compliant PSE switch. The input voltage range is 10-60V.
The positive input voltage and ground must be applied on specific data pairs
unlike the 802.3at architecture. The positive input must be applied on the pin 1-2
and pin 4-5 data pairs and ground must be applied on the pin 3-6 and pin 7-8
data pairs.
The data pairs for Passive Power over Ethernet have a 0.8A current limit. It may
be necessary to increase the input operating voltage to deliver the power needed
for the Mini-PCIe radios and USB charging ports. As an example, assume the
application includes a high power radio card that requires a total of 8W and a
USB device that requires a total of 7W. The required power is 15W for the
peripherals plus 4W for the SBC. The total power requirement is approximately
21W assuming 90% efficiency for the primary power supply.
More PoE information is available on the Gateworks wiki here:
http://trac.gateworks.com/wiki/poe
GATEWORKS.COM 3026 S. Higuera St San Luis Obispo, CA 93401
P:(805)781-2000
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